Catherine Dacremont

Wender Bredie

Stéphan Marette

Katherine Appleton

Laurent Muller

Benjamin Delessert

A Galiñanes Plaza

J Delarue
email: julien.delarue@agroparistech.fr

L Saulais

A. a,b , Saulais, L. c,b , Delarue Galiñanes Plaza

l'appréciation d'un repas. Du laboratoire à la vie réelle

Keywords: context effects, hedonic evaluation, reference points, food preparation, expectations, information xi effets de contexte, évaluation hédonique, points de référence, préparation des aliments, attentes, information Consumer experience, contexts, food preparation, affective experience, expectations, beliefs PART

committee. Thanks for our discussions and your advices about the experimental

ii positivement d'une manière ou d'une autre à mon parcours. Merci pour nos échanges et vos conseils.

Thanks to all the international colleagues I have the pleasure to meet at the Research Center of the Institut Paul Bocuse. Thanks to Herb Meiselman for your exchanges about context. It was a pleasure for me to meet you and have the opportunity to discuss with you about this "crazy" topic. Thanks for taking the time to read and comment my papers before submission and thanks for your always positive and encouraging words.

Thanks to the colleagues from Bournemouth University, specially Jeff Bray for your help with the focus groups and the good moments at Lyon Beer Festival.

Grazie ai colleghi dell'Università degli Studi di Firenze. Grazie di tutto ad Erminio Monteleone e Sara Spinelli. E' stato un grande piacere conoscervi e discutere con voi sia scientificamente che personalmente. Grazie per il brillante corso sul "Understanding Consumers" a Firenze, per la passeggiata ed i gelati. Maria, anche a te devo un sacco di cose. Sei bravissima! Il tuo soggiorno a Lione mi ha fatto tantissimo bene... le risate, le discussioni, la cucina...tutto. Veramente ti ringrazio! Thanks as well to the colleagues from Copenhagen University. Thanks Wender, Sandra, Armando, Belinda and Charlotte for having welcomed me in your department for a month. It was an amazing and valuable experience. Thanks Dwi, Xiao, Yang, Nethe and Alina for all the moments sharing together (usually around food and drinks) in France, USA and Copenhagen.

La thèse, veut dire aussi « école doctorale », merci Alexandre et Irina pour votre bienveillance et votre savoir-faire. Grâce à ces moments de partage par téléphone ou lors des entretiens annuels, j'ai su prendre du recul et trouver la lumière au bout du tunnel.

De plus, la thèse ne serait possible sans partenaires et participants. Merci à Bonduelle et au CROUS pour votre intérêt pour mon projet. Merci aussi aux participants sans qui cette thèse ne serait toujours qu'une question de recherche sans réponse.

Bien évidemment, si je suis là en train d'écrire ces remerciements, c'est parce que j'ai eu l'énorme chance de rencontrer des personnes incroyables tout au long de ces trois ans et demi. Merci Raphaëlle pour être toujours là avec une sourire et Bénédicte pour tes mots toujours positifs. Merci Olga pour ton accueil depuis le début, pour cette soirée aux péniches et nos rigolades. Merci Laura, Marine et Fanny pour votre aide au cours des expérimentations, vous m'avez sauvée ! Merci au pôle R&D, Julien et Florent pour votre aide dans la préparation des produits ; merci Estelle pour ta bonne humeur et les moments de folie, n'oublie pas notre « build your adri gali » ; et bien sûr, merci Céline d'avoir été ma iii partenaire à AgroParisTech pendant les cours de stats, pour être la « chef » qui a sauvé mes premiers terrains et pour tous les moments ensemble soit dans la voiture ou autour d'un verre et des fromages ! Merci aux chargés de recherche Maxime, Jérémie et Anestis pour vos conseils scientifiques toujours très pertinents et les moments partagés ensemble soit autour d'un verre, lors d'une pétanque ou encore pendant les soirées jeux. Et merci à ceux qui ont fait partie, à un moment ou à un autre, de cette aventure : Mamadou, Nelly et Chelo. Gracias por esos ratitos en español y las sesiones de yoga ! Et enfin, merci à la team doctorants et docteurs, mais aussi amis. Merci Erika, Marie, Fairley, Rafa et Abi pour vos conversations et vos soutiens. Je vous souhaite le meilleur ! Un merci particulier à ceux qui sont devenus d'une certaine façon ma famille en France (bien sûr je pleure déjà) : merci à Kenza pour ta positivité, pour me faire sourire et pour tes conseils gastronomiques ! ; merci à Camille M, ma co-équipière, tu es tellement riche de culture que chaque discussion avec toi a été un apprentissage pour moi ; merci à Sonia, ma partenaire jusqu'à la fin, ça a été difficile mais on y est arrivé ! « Force et honneur ! » n'oublie jamais ça ! ; merci à Blandine, pour ta folie, les moments partagés au théâtre, court-métrages, soirées jeux, pour ton aide avec ces fameux groupes de discussion, et pour ton petit (obligée de le mentionner) ; et un grand merci à AnneCé, Camille, Gaétan, avec une mention spéciale à Anastasia et Jérémy. Qu'est-ce que j'aurais fait sans vous ? Je n'ai même pas de mot pour vous remercier de tout ce que vous avez fait pour moi. Merci pour les soirées, nos discussions thèse, les corrections de grammaire et prononciation, pour les rigolades, les balades et encore tant d'autres choses, muchas gracias por todo amigos ! Merci, Thanks and Gracias aux colocs : Marlène, Nico, Thomas, Oriana, Elise and Sergio. Thanks Daniel for our conversations, movie or GOT nights, the cookie dough ice cream and your support! Gracias Iris por acogerme cada vez que voy a Paris, por nuestras conversaciones nocturnas y por aficionarme al yoga y a la meditación.

Thanks as well to my FIPDes colleagues, specially Daniela for your support and hosting me in Paris each time I needed, Gaby, Paco, Lizy, and Silvia for always supporting me. Thanks to FIPDes I had the possibility to travel to Naples and meet Nicoletta and Rossella. Grazie a voi ho scoperto quest'area di ricerca. Sarò sempre grata per il vostro sostegno, la vostra conoscenza e la vostra gentilezza.

Thanks to the « Undernations Team » for making me disconnect from the thesis. Thanks Mirte, Piter, Clare, David, Kim, Enisa, Soraya and Roman for the hiking, camping, biking sessions, etc. It is great to have people like you around and I promise I will bike soon again! iv Gracias Loreto por haberme llevado contigo al «Camion du Coeur» y haberme cambiado la perspectiva de las cosas. Merci à toute l'équipe du mercredi pour les soirées au camion, pour votre bienveillance et pour m'avoir montré que partager du temps avec ceux qui ont besoin d'un mot ou un sourie, ça ne coute rien et ça fait du bien au coeur.

Merci aux amis de Tib, que je considère comme mes amis aussi, spécialement, Gus, Marine, Mich, Clém, Daniel, Maud, Pauline et Guillaume. Merci pour les soirées jeux, les barbecues et les moments partagés.

Merci à ma belle-famille, une belle-famille que je n'aurais jamais pensé rencontrer trois ans auparavant et qui m'ont accueillie et soutenue durant ces trois ans comme s'ils étaient ma propre famille. Merci Caroline pour ta bienveillance ; Lukas, Camille, Emilie et Pierre pour les soirées séries, les rigolades et les moments partagés, vous êtes fous mais c'est ça que j'aime ; merci Fabien, Marion, et aux enfants car même si vous êtes loin, je tiens à vous. Merci aussi à Patrick et Roselyne pour les repas ensemble et votre soutien.

Y para acabar, vuelvo a mis raíces intentando que mi español no haya cambiado mucho. Gracias a mis amigos incondicionales donde las haya. Gracias Martus porque siempre estás ahí, aun en la distancia, eres mi medio cerebro que sabe que cuando rio y lloro a la vez es que la cosa esta chunga. Gracias Lau y Mary por ser mis compañeras fieles de nutri y Latinada. Porque, aunque nos veamos poco, sé que puedo contar con vosotras. Gracias a mis madridejenses favoritos, Esme, Cone, Edu, Marimar y Tere, os quiero no sabéis cuanto y os llevo conmigo siempre. Y gracias a ese grupo de hermanas que se ha convertido en la familia que uno escoge y que la vida le regala. Gracias Lara, Patri e Isa por estar a las duras y a las maduras, por decirme las verdades a la cara, aunque duelan y por sacarme una sonrisa cuando más lo necesito. Gracias Lari por enseñarme que la vida hay que vivirla y que lo que los demás digan importa poco o nada. Gracias Bea, Fresno y Maure por enseñarme que la amistad puede mover montañas y que los amigos son lo más bonito que hay. Gracias Cora por mostrarme que los sueños se pueden cumplir. Gracias Raqui y Pauli porque sois un ejemplo de lucha y superación. Y gracias María, porque desde ahí arriba nos has unido más que nunca y eso te lo debemos a ti. Gracias a mi familia, de la cual no puedo estar más orgullosa. Gracias papa y mama, por haber hecho de mis hermanas y de mí, mujeres curiosas e independientes. Si hoy estoy aquí es gracias a vosotros.

Gracias por haberme dado una educación inmejorable, por haberme apoyado en todas mis decisiones aun sabiendo que ellas conllevarían el estar lejos de casa. No ha sido fácil, pero vosotros siempre, siempre habéis estado ahí. Siempre habéis confiado en mí, incluso cuando yo ya no creía. Por todo ello, gracias infinitas. Gracias a mis hermanas que son un ejemplo de superación constante. María y Ale, os quiero y admiro muchísimo. Gracias a mis tíos, primos, padrinos por extensión y abuelos por apoyarme en la distancia y siempre estar ahí cuando regreso a casa. Gracias abuela Julia porque sé que desde ahí arriba me has ayudado a seguir adelante. Sé que estarías orgullosa de mi, igual que yo lo estoy y estaré siempre de ti. Gracias por hacerme cada día un poquito más fuerte. v Por último, gracias a ti Tib. Gracias por aguantarme durante estos casi tres años. Gracias por tu paciencia, tu confianza plena, tu buen humor, tus cursos de cocina, tus clases de conducir… Gracias por enseñarme a disfrutar de las pequeñas cosas y, sobre todo, gracias por hacerme mejor persona. Te quiero.

vi vii A Julia "My mother always taught us that if people don't agree with you, the important thing is to listen to them. But if you've listened to them carefully and you still think that you're right, then you must have the courage of your convictions."

Jane Goodall viii ix

SUMMARY

Environmental factors modulate consumers' perception and in turn, consumers' evaluation of food in a given context, either directly or through context-induced beliefs and expectations. However, food products are usually evaluated in standardized conditions in an attempt to neutralize possible context effects on consumer evaluation. This questions the generalization of such measures to more natural consumption contexts.

The aim of this research was to examine the conditions under which context affects consumer evaluation of food products. This work is grounded in Prospect Theory, which considers the effects of context on judgement through the notion of reference points.

The first objective was to understand how consumers' experiences and subsequent product evaluations are influenced by consumers' representations about food in different consumption contexts. A qualitative study (12 focus groups; N =86) revealed that consumers' beliefs and expectations towards a particular context are intimately associated to different types of products and culinary methods, and that external factors have a different weight depending on the consumption context.

The second objective was to understand how consumers' hedonic responses in natural consumption contexts may differ depending on the type of evaluation task. The hedonic responses of products with different degrees of culinary preparation (bread = control; pizza = homemade, industrial and mixed)

were compared (N = 457) between two different tasks in a student cafeteria. The results showed that multicomponent products subjected to a different degrees of culinary preparation (homemade pizza)

were indeed more sensitive to the type of evaluation task compared to more standardized products (bread).

The last objective of the thesis was to test hypotheses based on Prospect Theory to explain contextual influences on consumers' food evaluation. Two experiments compared hedonic evaluations in (i) two contexts (CLT and restaurant;N= 283), in blind and informed conditions about the degree of culinary preparation of a product (ham-olive cake); and (ii) in one context (restaurant; N = 114) in informed conditions about the degree of culinary preparation and origin of the ingredients (quiche); where consumers' beliefs and expectations towards the food served were modified. Results showed that the effects of external factors could be reduced through careful control of consumers' beliefs and expectations in a given context.

This thesis contributes to the understanding of context effects on consumer hedonic evaluation and it proposes a theoretical framework to investigate those effects by means of reference points. The results could be valuable to develop guidelines for industrials and researchers using hedonic evaluations to include context adequately at each stage of product development.

x

GENERAL INTRODUCTION

Why aren't products equally appreciated at home, at a restaurant or at a consumer test laboratory?

Is it a matter of context? A matter of product? Or it is because of the consumers?

Those questions set the starting point of the present work. Context has an impact on consumer evaluation that involves multiple factors difficult to disentangle. A product can perfectly fit in a particular context whereas it may not do so in another one. This can be explained by means of the physical context, by means of differences in the food preparation, or through consumers' expectations and beliefs towards a particular product in a particular context.

The issue of context was pointed out by Meiselman in 1992 regarding studies on human eating behavior. He argued that eating behavior cannot be studied without the consideration of "real food" in "real" contexts. Consumers' eating decisions in "real" context may be influenced by "situational, economic and social constraints" that studies in controlled conditions such as laboratories may not include (Meiselman, 1992, p.50). In 2017, the sensory and consumer science field also highlighted the consideration of context as one of the four most important perspectives for the future of the discipline (Jaeger et al., 2017). Generally, consumers' tests have been done in controlled conditions. However, the lack of realism in those tests has been associated to a lack of ecological validity on consumer evaluation which can be translated in a lower reliability of consumer tests data. Thus, the generalization of data from consumer tests in controlled conditions to "real-life" contexts is questionable (Köster, 2003).

The numerous failures of market launches for new products have been attributed to this lack of ecological conditions in consumer tests (Köster & Mojet, 2012a). Liking a product in a consumer tests does not guarantee that the product will be purchased and consumed. As Meiselman argued about consumers' eating behavior, situational aspects may be considered in order to understand how and when products are consumed. Fast Moving and Consumer Goods companies launch products to the competitive market every day. However, between 80 and 90 per cent of new launches are taken out of the food and beverage market within a year (Köster & Mojet, 2012a). In 2016/2017, FMCG invested €2.9 billion in Research & Development (R&D) (FoodDrink Europe, 2018). Consequently, companies cannot neglect the huge loss of money and time that those launch failures may cause. Therefore, the debate about ecological conditions on consumer tests does not only affect research but industry.

In the last decade, several contextual methodologies have been developed in order to gain in ecological validity and increase the generalizability of experimental data (Jaeger & Porcherot, 2017).

Evoked contexts (Hein, Hamid, Jaeger, & Delahunty, 2010), immersive scenarios (Hathaway & General Introduction Simons, 2017) or the use of virtual reality (Andersen, Kraus, Ritz, & Bredie, 2018) are some of the contextual approaches used by sensory and consumer practitioners to bring context (or contextual elements) to the laboratory and ensure in a certain way the success of products.

However, how and to which degree context influences consumer evaluation is still unclear. The lack of a theoretical framework behind context studies makes it difficult to understand the role played by contextual variables in consumer evaluation. Yet, consumers may have a different frame of reference depending on the situation, and this may be the case at different levels: at the context level, the product level, or the consumer level. This difference in the evaluation framework may directly impact consumers' hedonic judgement. Therefore, the role of the evaluation task should be also considered when performing context studies in order to improve the generalizability of the results.

Within this context, the present PhD project, started in February 2016, is a joint initiative by the University of AgroParisTech, the Institute Paul Bocuse Research Center (IPBRC), and the Scientific Society of Food Hygiene (SSHA), which financially supported the project. The theoretical aim is to understand and examine the conditions under which context affects consumers' evaluation of food products. This work is grounded in Prospect Theory [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF] which considers the effects of context on judgement through the notion of reference points. The practical aim of this research is to inform professionals and scientists who use hedonic evaluations about the inclusion of context at each stage of product development.

The present thesis dissertation comprises nine chapters, articulated in five parts. It begins with a review of current literature on context studies, and a presentation of the research hypotheses (Part A, chapters 1-4). The review is split into three chapters. First, a review of context and its effect on consumers' hedonic judgement is presented (chapter 1). The second part of the review is presented as a paper written in journal format focused on the ecological validity of context studies (chapter 2). The review concludes with a theoretical framework proposal to study context effects (chapter 3). Part A ends with a presentation of the problematic and research hypotheses (chapter 4).

Part B contains two chapters associated to a preliminary phase to the present project (chapter 5 and 6).

Chapter 5 presents a preliminary study where the effects of context on consumer hedonic evaluation are assessed within blind and informed conditions when product-related variables are standardized.

Chapter 6 includes an exploratory study that aims to investigate the effect of food information on consumers' choice and hedonic evaluation in a natural consumption context.

Part C contains one chapter (chapter 7), presented as a paper written in journal format. This chapter presents a qualitative study that aims to understand how consumer experience is influenced by consumers' representations about food in different consumption contexts.

General Introduction

Part D contains one chapter (chapter 8) also presented as a paper written in journal format. Chapter 8 presents a study that examines how consumer hedonic evaluation in a natural consumption context differs depending on the type of evaluation task.

Part E aims to understand how framing effects related to the task modulate consumer hedonic evaluation based on Prospect theory. It contains one chapter (chapter 9) that includes two studies presented as a paper written in journal format. The first study examines the influence of context on consumer hedonic evaluation of two products with different degrees of culinary preparation associated to different consumers' beliefs and expectations. The second study assesses the influence of the type of information (consistent or inconsistent with consumers' expectation and beliefs) on consumer hedonic evaluation of a product in a natural consumption.

This work concludes with a general discussion that gives an overview of the thesis as a whole, including a summary of the main findings and the contribution of the empirical chapters (5-9) to current understanding the conditions under which context affects consumer hedonic evaluation of food products.

PART A. LITERATURE REVIEW AND RESEARCH HYPOTHESES

PART A: Literature review and Research Hypotheses Chapter 1. The effects of context on consumer's judgement I love "churros con chocolate". A traditional dish and a hot drink from Spain, usually consumed at breakfast. When I go back home, I always buy the churros in the small truck in front of my house. I really like to have this food for breakfast. However, their taste has nothing to do compared with the churros con chocolate I had when I was a child in the cafeteria close to my grandparents' house.

This discrepancy could be explained by the simple fact that the preparation between the two contexts may have differed, modulating my global judgement. However, other factors may have been included

in the formulation of this judgement as the product experience is inscribed in one or several contexts.

If I think about the churros con chocolate that I had when I was a child, I am thinking about the physical context of the cafeteria, the nice ambiance, the feelings that this ambiance induces, and all of that is related to the food. So, when I formulate a judgement about the churros con chocolate, I am going to consider not just the product but different external factors. If I think about the churros con chocolate in another context, just the modification of the physical context and the ambiance associated to this new context may change my personal judgement as well.

In consumer tests, food products are hedonically evaluated in controlled conditions. The evaluation tasks are designed so that consumers focus on the product rather than on external factors. However, the lack of realistic conditions implies that the judgement about a product in the laboratory may not be representative of a judgement about the same product in natural consumption contexts.

This first chapter introduces two of the key elements of the thesis: consumer hedonic evaluation and the role of context. First, consumers' hedonic judgement and behavior are introduced. Then, definitions about context and contextual variables are given. A review of the effects of context and contextual variables on hedonic judgements is then presented. The chapter ends with a discussion of context studies and ecological validity.

Consumer hedonic judgement and behavior

Before starting this section, two main concepts should be defined: judgement and behavior.

A judgement is an evaluation of something like an object or a situation. Hedonic judgements are evaluations of product's attributes that determine, in part, if a consumer likes or dislikes a product.

Behavior is defined as the sum of actions one conducts. Eating behavior involves the selection of products (choice) and their consumption (intake).

When we elaborate a judgement different cognitive processes are involved. According to Stanovich & PART A: Literature review and Research Hypotheses [START_REF] Stanovich | Individual differences in reasoning : Implications for the rationality debate ?[END_REF], we have a dual system that codifies the information we perceive and translates it into a judgement:

1. System 1, composed by perception and intuition, is characterized by processes that are "fast, automatic, effortless and associative" 2. System 2, reasoning, is characterized by "slower, serial, effortful and deliberately controlled processes" (Kahneman, 2002, p.450) When we eat, the mechanisms behind the judgement formation are used to translate the sensory properties of a particular product, perceived by our senses, into a hedonic perception. This process occurs automatically and we do not have any control over it. However, when consumers participate in a test, they perform two different tasks. The first one, tasting it is more prone to activate system 1, perception; and the second one, answering a question, that activates system 2, reasoning. The switch between both systems makes us to formulate a more explicit answer. The fact of asking a question highlights different aspects of the product (framing effects). This modulates our perception in an unconsciously way and "forces" us to give a more conscious and explicit judgement (Dijksterhuis, Smith, van Baaren, & Wigboldus, 2005). [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF] illustrates framing effects with an example of letters and numbers. If we observed the Figure 1 we identify the letters A, B and C, and the numbers 12, 13 and 14, our System 1 is activated. However, we also perceived that letter B and number 13 can be interpreted in a different way. Conversely, if we cut the figure in two lines, we will not have the same access to the information and we will perceive and interpret the letter and number in its contexts. A parallel can be drawn when consumers evaluate products during a test. When we evaluate three products in a consumer's tests, we frame our perception towards those three products in that particular contexts; whereas in a more complex or natural consumption situation, different information will surround us, which may affect our perception and then our judgement.

Figure 1. Effects of context on consumers' perception (Retrieved from [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF].

PART A: Literature review and Research Hypotheses

In natural consumption contexts, multiple factors external to the product are likely to influence our judgement and our behavior: the environment where we eat, with who we eat, our psychological and physiological state, etc. Factors that are going to unconsciously influence our perception and then, judgement. Figure 2 shows a model proposed by Mojet (Köster, 2009) mapping essential factors in the study of consumers' eating and drinking behavior, and showing the complexity that surrounds consumers' hedonic judgements and behavior.

Figure 2. "Essential factors that influence eating and drinking behavior and food choice" according to Mojet (Retrieved from Köster, 2009, p.72).

When studying consumers' hedonic judgement in consumer's tests, we avoid somehow the interaction with all those external factors described by Mojet (Köster, 2009). In the last decade, the way to approach consumers' judgement and behavior has been the center of a debate between sensory and consumer scientists, and psychologists. Köster (2009) highlights the differences between disciplines and underlines the importance to move from a reductionist approach to a deductionist approach.

Reductionist approach means consumers' judgements and behaviors are studied by the modulation of separate variables chosen by the researchers. For example, considering Kahmenan's letters and numbers example, consumers evaluate A, B and C or 12, 13 and 14. Conversely, a deductionist approach means that consumers' judgements and behaviors are studied in more complex conditions closer to the natural consumption situation. For example, consumers evaluate A, B, C, 12, 13 and 14.

PART A: Literature review and Research Hypotheses Thus, when studying consumers' hedonic judgement in different contexts, we need to first understand the factors (contextual variables) that may influence consumers' perception in a particular context and second, how the use of questions and scales are going to frame those factors modulating consumers' perception and in turn, consumers' hedonic judgement. Therefore, two levels of context effects are presented.

Context and contextual variables: definitions

"The actions people take are affected by a dazzlingly complex set of relational situations, social norms, frames, past experiences, and the lessons gleaned from those experiences. Consequently, the experimental investigator often lacks complete control over the full context within which the subject makes decisions" (Levitt & List, 2007, p. 162).

Context has an impact on consumers' hedonic judgement which makes it relevant for the performance of consumer tests. The lack of consideration for context when implementing a consumer test has been seeing as the lack of ecological conditions and therefore, has aroused the question of ecological reliability. Not only researchers but also industrials have questioned this, due to the high number of new products failures in the market (Köster & Mojet, 2012a;[START_REF] Köster | Flops analysis : a useful tool for future innovations (Part 2 : The reduction of future flop risks)[END_REF] Context is a very broad concept that has been indistinctly used in the scientific literature as environment, setting, location and/or situation. Meiselman (2006) refers to it as specific physical, social and situational conditions in which food and beverages are consumed. Hence, conditions that are going to influence consumers' hedonic judgement. For the purpose of this thesis, context refers to specific environment where social interaction may or no occur, in which food and beverages are consumed, and evaluated. In the sensory and consumer research literature, context is considered mainly in two ways. The first approach considers context as a whole (as defined by Meiselman), and the second approach considers the presence or absence of some specific contextual variables in a given context.

Several typologies of contextual variables have been proposed in the literature. Rozin & Tuorila (1993) classify contextual variables in simultaneous (where "contextual factors are physically present during the reference event" p.12) and temporal ("past or anticipated future events that enter the mind of the subject at the time the reference event is occurring" p.12), size of the eating reference unit (bite, dish, meal), and type of contextual variables (food or non-food related); Meiselman (1996) proposes a three classification of contextual variables based on the situation, the individual and the product; whereas Stroebele & De Castro (2004) classify the contextual variables in social variables, physical PART A: Literature review and Research Hypotheses surroundings, time related characteristics and distractions. Meanwhile, [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF] includes physical environmental variables and consumer variables within the context, and at the same time classify physical environmental variables in those related (or not) to the product and the consumer variables in stable and punctual.

Contexts effects influence consumers' hedonic perception, so consumers' judgement. However, the lack of ecological conditions in consumer tests, compromise the generalization of results from controlled conditions to natural consumption contexts. Moreover, in consumer tests, the use of questionnaires or scales, also influence the way in which consumers perceive those factors and in turn, their hedonic judgement. Considering that, and the lack of consensus among previous classifications, we classified the contextual variables in four categories that correspond to the features needed to determine if an experiment is ecologically valid or not (Galiñanes Plaza, Delarue, & Saulais, 2019).

This classification includes the environment in which consumers perceive a product, the product evaluated, the consumer who evaluate the product within the environment, and the evaluation task that takes place in that environment (Figure 3). Within each category different contextual variables that may influence consumers' perception and that have aroused the interest of some researchers in the field have been considered. Regarding the environment, variables such as the physical situation, the ambiance and the social interaction have been considered; for the product the eating reference unit proposed by Rozin & Tuorila (1993), the presentation and the preparation of the product have been investigated; for the consumer her/his psychological status, past experiences and beliefs, products' familiarity and involvement have been explored. Finally, for the task, the experimental procedures, instrumental measurements, the attention demand to perform the task and the incentives have been included.

Effects of context and contextual variables on consumers' hedonic judgement

In the following section, a review of the contextual variables classification and their effects on consumers' hedonic judgement is presented. The work done by [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF] has set the bases for this review and it has been completed with recent research on context studies, and the contextual variables of interest.

Contextual variables: environment

Several studies have reported differences in consumers' hedonic judgements of a same product in varying environments (we will consider the environment as the physical context) which include variables such as the ambiance and social interaction (Boutrolle, Arranz, Rogeaux, & Delarue, 2005;Edwards, Meiselman, Edwards, & Lesher, 2003;King, Weber, Meiselman, & Lv, 2004). Those differences have been associated to higher liking scores and discrimination when consumers taste products in more natural conditions. However, those results are not conclusive.

3.1.1. Factors related to the ambiance such as the colors [START_REF] Cho | Blue lighting decreases the amount of food consumed in men , but not in women ☆[END_REF]Sester et al., 2013;[START_REF] Spence | A large sample study on the influence of the multisensory environment on the wine drinking experience[END_REF], decoration (Bell, Meiselman, Pierson, & Reeve,1994) and sounds [START_REF] Spence | The influence of auditory cues on the perception of, and responses to, food and drink[END_REF] have been pointed out as some of the causal factors for the changing in food perception though cross modal interactions.

3.1.2. Moreover, social interaction within a particular environment has also shown to modulate consumers' behaviors in different ways, specially depending on the degree of familiarity among consumers (Di Monaco, Giacalone, Pepe, Masi, & Cavella, 2014;[START_REF] Robinson | Awareness of social influence on food intake. An analysis of two experimental studies[END_REF]. However, no clear evidences are found as regards consumers' hedonic judgement.

Environment-related variables may modulate consumers' hedonic judgements. However, how those environmental variables affect consumer hedonic evaluation is still unclear as there is no standardization in the way they should be used. Moreover, the interaction between several environmental variables at a time may occur being difficult to disentangle the causal relation between PART A: Literature review and Research Hypotheses consumers' hedonic judgement and one specific environmental factor. Additionally, we may consider that consumers' expectations towards a particular physical context may also differ, affecting in turn consumers' hedonic perception (Köster, 2003). Hence, this may affect the comparison between context studies and the generalization of results from one context to another.

For further discussion about the effect of environmental variables the reader is directed to [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF]. Moreover, the review carried out by [START_REF] Cruwys | Social modeling of eating: A review of when and why social influence affects food intake and choice[END_REF] about the social influence on consumers' behavior is also recommended.

Contextual variables: product

When we eat or drink we formulate conscious and unconscious judgements about the product. The product itself, its organoleptic characteristics, are going to influence consumers' perception. However, there are other variables such as the quantity of the food and its presentation that are going to impact consumers' hedonic judgement, for example through the mechanisms of satiation [START_REF] Meillon | Sensory-specific satiety for a food is unaffected by the ad libitum intake of other foods during a meal. Is SSS subject to dishabituation[END_REF] or cross modal interactions [START_REF] Zellner | temps que ces échecs de lancement peuvent causer. Le débat sur les conditions écologiques des tests de consommation n'affecte pas seulement la recherche[END_REF].

Product-related variables include all the contextual characteristics that define the product beyond its sensory properties -from the quantity of food tested (referred to as the eating reference unit) to the type and number of other foods offered (or not) in combination to the evaluated product, but also the way the food is presented and the process of its preparation.

3.2.1. The eating reference unit is a concept defined by Rozin & Tuorila (1993) that refers to the size of the tested food (bite, dish, meal) over time. Each reference unit has a different level of complexity, temporal and spatial importance as well as research application. For example, in consumer tests participants usually taste a bite of a product in a short period of time while a meal involves more complex elements and it demands a longer period of tasting [START_REF] Hyde | Dynamic contract: A sensory contribution to palatability[END_REF].

3.2.2. Combinations of foods are rarely seen in laboratory contexts, where the studied food products are generally evaluated as single items (bite or dish) rather than as part of a meal.

However, several studies have shown that products evaluated as part of a meal were higher rated than individual items (King, Meiselman, Hottenstein, Work, & Cronk, 2007;King et al., 2004). The definition of "meal" is vague and depends on the researchers' orientation. Meals are food eaten as part of a structured event, following rules of combination and sequence; however, snacks are unstructured food events which do not follow any rules concerning time, place or sequence (Pliner, Bell, Road, Bell, & PART A: Literature review and Research Hypotheses Meiselman, 2004). In this case, we may consider that depending on the event (meal or snack) the hedonic judgment and behavior may differ (De Graaf et al., 2005;King et al., 2004).

Regarding the rules of combination and sequence, most of the research on eating behavior has focused on food items instead of food combinations. Nevertheless, in the last fifteen years, researchers have shown that suitable food combinations result in more pleasant recipes, thus in higher overall liking scores [START_REF] Elzerman | Appropriateness, acceptance and sensory preferences based on visual information: A web-based survey on meat substitutes in a meal context[END_REF]Pagliarini, Gabbiadini, & Ratti, 2005); and others researchers have also studied how much of each meal component contributes to that hedonic judgement (Jimenez et al., 2015;Meiselman, 2006). Moreover, the sequence and appropriateness of mealtimes when evaluating products have also shown to influence hedonic judgements (Boutrolle & Delarue, 2009;Cardello, Schutz, Snow, & Lesher, 2000).

3.2.3. Regarding food presentation, we may include not only the dish but the cutlery. Several studies have shown the impact of cutlery on consumers' hedonic perception and judgement in natural contexts (Piqueras-fiszman, Alcaide, Roura, & Spence, 2012;

Piqueras-Fiszman, Laughlin, Miodownik, & Spence, 2012;[START_REF] Spence | On the multiple effects of packaging colour on consumer behaviour and product experience in the 'food and beverage' and 'home and personal care' categories[END_REF].

However, when looking at consumer tests, this variable is rarely considered.

With regard to the platting, the expression "you eat first with your eyes" easily explains how the visual composition of a product or a dish may affect consumers' perception so, consumers' judgement. Some researchers have shown their interest on the effect of subtle changes in the visual presentation of a dish on flavor perception and consumers' liking. [START_REF] Zampollo | Food plating preferences of children: the importance of presentation on desire for diversity[END_REF] showed the effect of food presentation on children preferences by modifying the number of items and their distribution on a plate in a school. [START_REF] Zellner | Neatness counts. How plating affects liking for the taste of food[END_REF] showed that a neatness presentation increased consumers' liking and also their Willingness to Pay (WTP), whereas [START_REF] Michel | Studying the impact of plating on ratings of the food served in a naturalistic dining context ☆[END_REF]Spence, 2015 andMichel, Velasco, Gatti, &Spence (2014) found opposite results.

Within this variable, Sester (2013) also include packaging and labelling. The role of information has shown to influence consumers' beliefs and expectations modifying consumers' hedonic judgements and behaviors [START_REF] Bernard | Do labels that convey minimal, redundant, or no information affect consumer perceptions and willingness to pay?[END_REF][START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Mcfadden | Cognitive biases in the assimilation of scientific information on global warming and genetically modified food q[END_REF]. The fact of priming over a particular product aspect frames consumer evaluation, and then consumers' perception as certain characteristics of the product become more salience.

3.2.4. The concept of food preparation has been widely used in the scientific literature referring to different meanings ranging from the way consumers taste products to the actual PART A: Literature review and Research Hypotheses preparation method or culinary technique, the presentation of food samples in the laboratory [START_REF] Siret | Traditional process: influence on sensory properties and on consumers' expectation and liking Application to 'pâté de campagne[END_REF] and the served temperature [START_REF] Cardello | Acceptability of Water, Selected Beverages and Foods as a Function of Serving Temperature[END_REF][START_REF] Kähkönen | Dairy fat content and serving temperature as determinants of sensory and hedonic characteristics in cheese soup[END_REF].

According to Delarue & Boutrolle (2010), individual food preparation is involved in the formulation of the hedonic judgement. Several studies have shown a direct effect on liking and products' discrimination when consumers have the freedom to taste and prepare the products according to their own consumption habits (Hathaway & Simons, 2017;Posri, Macfie, & Henson, 2001). However, little research has been carried out in laboratory contexts.

Food preparation as culinary techniques or methods has also proved to modify the perceived sensory properties of a product, thus the hedonic judgement. A product prepared at home may differ from another one prepared at the restaurant or at the laboratory contributing to the negative correlations between the hedonic judgements at laboratory and natural consumption contexts (De Graaf et al., 2005). Moreover, the culinary preparation seems to be related to consumers' expectations and preference for products or dishes in particular contexts (Edwards, 2013).

Product-related variables show to have an impact on consumers' hedonic judgement that goes from a simple bite to the preparation of the product. When looking at context studies, especially at consumer tests, special attention should be put on each of those variables. If the environment has already shown to influence in a certain way consumers' hedonic judgement, the fact of include variability in the way products are tested may induce higher differences in how consumers perceive the product. In general, in consumer tests small portion sizes of the products are presented usually in plastic cups and dishes.

They are not included as part of a meal or an eating situation and they are served ready to consume, so no preparation from the consumer side is needed. All those aspects have shown to matter for consumers when they formulate a judgement. Therefore, they cannot be neglected.

Contextual variables: consumer

Consumers' physiological, psychological status and food habits are some of the consumer-related variables that have shown to influence consumers' hedonic judgements. In this section only the variables treated in this thesis and those not examined by [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF] are presented. However, for further discussion about the effect of consumer-related variables such physiological or cultural variables the reader is directed to [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF].

PART A: Literature review and Research Hypotheses Within the consumer-related variables consumers' emotions, mood, expectations, beliefs and past experiences, product familiarity, and consumers' involvement have been considered.

3.3.1.

Consumers' emotions and their relation with consumer hedonic judgement and behavior have become one of the most explored areas of research in the past years (Jaeger et al., 2017;[START_REF] Meiselman | A review of the current state of emotion research in product development[END_REF]. Emotions do not have a consensual meaning within the scientific community. However, it is agreed the idea that emotions have "multiple components, including physiological arousal, motivation, expressive motor behavior, action tendencies and subjective feeling", and that they are characterized by "a synchronized response, rapidity of change, behavioral impact, high intensity and relatively short duration" (Spinelli, Masi, Dinnella, Zoboli, & Monteleone, 2014, p.110). Piqueras-Fiszman, [START_REF] Piqueras-Fiszman | Assessing the influence of the color of the plate on the perception of a complex food in a restaurant setting[END_REF] associated different emotions to different product categories and several evoked contexts. These authors showed that consumption context and contextproduct appropriateness impact consumers' emotional associations. Neutral categories such as fruits showed more stable emotions along different contextual situations while categories such as chocolates or chips were related to an emotional eating strategy or satisfy cravings state. [START_REF] Gutjar | The role of emotions in food choice and liking[END_REF], and Köster & Mojet (2015) discussed about the need of emotions to predict consumers' choices as liking ratings often fail when envisaging market success or are insufficient to predict products acceptance.

3.3.2. The effect of consumers' mood on their hedonic judgement and vice versa has been also

shown through consumers' memories and expectations (Köster & Mojet, 2015).

Considering the effect of mood on food, in the study performed by [START_REF] Platte | Oral perceptions of fat and taste stimuli are modulated by affect and mood induction[END_REF] the intensity of sucrose and quinine as indicators of sweetness and bitterness perception was positively correlated to depression and anxious moods; whereas when studying the effect of food on mood results showed how carbohydrate and sweet food have a positively impact on consumers' mood [START_REF] Macht | Everyday mood and emotions after eating a chocolate bar or an apple[END_REF].

Regarding consumers' expectations, several studies have shown an interaction between

expectations and consumers' perception, judgement and behavior [START_REF] Delwiche | You eat with your eyes first[END_REF][START_REF] Schifferstein | Consumer expectations for vegetables with typical and atypical colors : The case of carrots[END_REF]. Expectations influence consumers' hedonic judgement trough top-down processes [START_REF] Lee | Try It, You' ll Like It[END_REF]. When consumers taste a product they tend to compare it to personal standards, mental representations, and from there elaborate a judgement. Effects of assimilation or contrast may then occur modifying the hedonic judgement depending on the distance between the actual perception and consumers' personal standard (Cardello, 1995;[START_REF] Davidenko | Assimilation and Contrast are on the same scale of food anticipated-experienced pleasure divergence[END_REF]. This is an PART A: Literature review and Research Hypotheses important variable as consumers' expectations may also differ depending on the environmental variables. Thus, consumers' personal standard may vary depending on whether they are in a consumer tests or at home or at a restaurant, and in turn the differences in hedonic judgements among contexts.

3.3.4. Beliefs and past experiences, have proved to impact consumers' hedonic judgement and behavior (Bernard & Liu, 2017;[START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF]van den Heuvel, van Trijp, Gremmen, Jan Renes, & van Woerkum, 2006). Beliefs "are statements of real or perceived knowledge about a product or object" (Kempen et al., 2017, p. 246) ruled by different cognitive process responsible of their updating when consumers face a new information [START_REF] Mcfadden | Cognitive biases in the assimilation of scientific information on global warming and genetically modified food q[END_REF]. They are related to consumers' past experiences with a product or a situation which may help to explain contexts differences when comparing consumers' hedonic judgements (Köster, 2003). When it comes to context studies it is important to keep in mind that consumers' beliefs and past experiences towards a particular context may influence consumers' perception. In the case of consumer tests, there is lack of information regarding what consumers think about this type of contexts. Nevertheless, this information could help to explain in a certain way contexts differences.

3.3.5. Consumers' product familiarity has also shown to impact consumers' hedonic judgement.

Most of consumer tests are performed with regular consumers of the target product.

However, when looking at context studies, unfamiliar products have shown to be more context-dependent than familiar ones (Giacalone et al., 2015;Kim et al., 2015).

3.3.6. The lack of consumers' involvement in consumer tests has also shown to influence consumers' hedonic judgement (Köster, 2009). [START_REF] Brien | What is User Engagement ? A Conceptual Framework for Defining User Engagement with Technology[END_REF] describes that consumers are motivated to participate in a task when they found the experience enjoyable and engaging. Recent studies have been interested in this area showing positive correlations between consumers' involvement in more natural contexts and products discrimination (Bangcuyo et al., 2015;Boutrolle, Delarue, Köster, Aranz, & Danzart, 2009;Hathaway & Simons, 2017). The fact that consumers are not involved in the task, as occurs with the preparation of the product, may reduce their interest, impacting on their hedonic judgement.

Consumer-related variables have shown to influence consumers' hedonic judgement. Therefore, when comparing context studies special attention should be put on those variables that may help to explain context differences. In consumer tests' it is needed to understand what consumer think and expect to find in this type of context. Context studies compare not only hedonic responses but consumers' food experiences, so defining those variables may help to explain the differences between controlled conditions and natural consumption contexts.

Contextual variables: task

The evaluation task is not usually considered as a contextual variable. However, when consumers formulate an explicit hedonic judgement it means that an evaluation task has been performed.

Moreover, regarding the problematic of ecological validity about consumer tests' data, it is important to understand if the task performed in a context is representative and relevant in the context of interest to ensure the ecological validity of the results (Galiñanes Plaza et al., 2019). Hence, the evaluation task performed within the environment of consumption has been considered as a contextual variable.

The effects of the evaluation task on consumers' judgement have been further studied by psychologists and behavioral economics [START_REF] Ariely | Tom Sawyer and the construction of value[END_REF]Harrisson & List, 2004;[START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF]. The framing of the evaluation task has shown to have a significant impact in the way that consumers perceive a specific task and integrate the information to formulate a judgement (Köster, 2009;Köster, 2003). When consumers receive the instructions to perform a particular task, the type of information given, the amount of given information and the way it is presented may drive the attention of consumers to particular features [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF][START_REF] Lee | Try It, You' ll Like It[END_REF]. This attention placed on the task may bias the actual perception and judgement of the consumer, so the reliability of the results (Dijksterhuis et al., 2005;Köster, 2003).

When eating or drinking, consumers make spontaneous judgements usually related to the fact they like or dislike a product. In consumer tests, hedonic evaluation task can involve global judgements that refer to a synthetic evaluation task or more detailed judgements, that refers to an analytical evaluation task. The latter involves the description of specific sensory characteristics of the products. This, may led to a more cognitive demand due to the attention consumer may place on it. This may then modulate the frame of consumers' perception, and in turn consumers' hedonic judgement.

The act of eating involves different cognitive processes (System 1) than the act of evaluating (System 2). Considering that, the features of the evaluation task as the experimental procedures and measurements tools (questionnaires, scales) may also influence consumers' judgement. In fact, several studies have shown that depending on the number of questions (Prescott, Lee, & Kim, 2011), PART A: Literature review and Research Hypotheses the order in which they are asked [START_REF] Earthy | Effect of question order on sensory perception[END_REF] and the way they are formulated (Jaeger et al., 2013;Popper, Rosenstock, Schraidt, & Kroll, 2004) may influence consumers' hedonic judgement:

a. Number of questions: higher number of questions about specific sensory product characteristics may inhibit or distort the cognitive representation of synthetic characteristics of the product (Prescott et al., 2011). That is that consumers focus on product characteristics instead of the global liking of the product. However, controversial results are found related to this issue (Jaeger et al., 2013).

b. Order of questions: Related to the previous factor, the order in which questions appears seems to also affect consumers' hedonic judgement. When a synthetic question such as the overall liking of a product is asked after the evaluation of sensory characteristics, the overall liking scores tend to decrease especially after the evaluation of negative attributes [START_REF] Earthy | Effect of question order on sensory perception[END_REF]. Consumers may concentrate their attention to those specific attributes modulating their perception of the product and then, their judgement. However, when the synthetic question is formulated before, those effects are not observed.

c. Formulation: as described before, depending on the way questions are formulated consumers' attention towards the product and its characteristics may vary. The salience of certain sensory characteristics may catch the attention of the consumers who are going to focus their evaluation and posterior judgement on those characteristics (Jaeger et al., 2013;Popper et al., 2004).

Moreover, research has been carried out on the use of hedonic scaling and the outcomes of those measurements tools (Cardello, 2017;Lim, 2011). Cardello (2017) insists on the fact that attention should be place in the way hedonic scales are selected, the end-point anchors established and the framing of the questionnaire set. All of that is going to impact the way in which consumers are going to evaluate a product and the way in which the researcher is going to analyze and interpret the data.

Within the evaluation task-related variables, another important variable that has not been deeply investigated in consumer's tests is the presence of incentives. In natural consumption contexts consumers usually pay for the food they consume whereas in consumer's test they are paid or compensate for doing it. Studies in experimental economics have shown how the presence or absence of an incentive can modulate consumers' involvement (Carson & Groves, 2007;Shogren, 2005).

Involvement has shown to influence consumer evaluation and consumers' judgement. Therefore, this PART A: Literature review and Research Hypotheses variable should be considered when comparing the results of consumer's tests and natural consumption contexts as it may help to explain certain differences.

Evaluation task-related variables have shown to influence directly and indirectly consumers' hedonic judgement. The frame of the evaluation task plays a key role on the way consumers perceive a product and judge it. When comparing context studies, it is important to consider that two contexts effects may occur: one at environmental level in which the product and consumer interact, and another one at evaluation task level within the environment. This means that by controlling the contexts effects at evaluation task level, the generalization of the results among contexts may be in a certain way ensured.

Conclusions

The present chapter has shown that contextual variables have an effect on consumers' hedonic judgement. The presence and/or the lack of contextual variables seems to modulate consumers' perception both in controlled conditions and in natural consumption contexts. However, it is still unclear the mechanisms behind those effects and this directly questions the reliability and ecological validity of the data obtained in controlled conditions; but also the ecological validity of the data when comparing different natural consumption contexts.

It has been shown that whereas environmental and consumer-related variables may be difficult to controlled, product and evaluation-task related variables may do. Concerning consumer-related variables, expectations and beliefs towards products have shown to modulate consumers' hedonic judgement. However, when comparing context studies, expectations and beliefs towards the contexts of consumption and evaluation may also influence the way in which consumers are going to perceive the product as part of the food experience. Therefore, special attention should be placed on those variables to explain in a certain level differences in hedonic responses. Moreover, when comparing context studies, product and evaluation task-related variables should be controlled to at least ensure the interpretation of context effects at evaluation task level. Variables such as the quantity of served food, presentation and preparation should be controlled in order to be comparable among context studies. Besides, consumers may evaluate the product differently in a consumer's test than in a more natural consumption context due to the presence of questionnaires and incentives. Therefore, special attention should be placed on those variables in order to ensure the representativeness of the task in the context of interest and their posterior comparison among contexts.

Introduction

Both academia and industry have identified a need for more ecologically valid methods in sensory and consumer research, in order to better understand consumers' behaviors and predict new products success. In the last decade, several methodological approaches have been proposed in response, mostly focused on the contextualization of evaluations, either through the addition of contextual referents in the physical environment or, more recently, through the use of virtual reality. However, in the absence of standardized criteria, the robustness and reliability of their results remains uncertain. This narrative review examines the notion of ecological validity from the perspective of different disciplines and proposes an analytical framework to evaluate the transferability of data in sensory and consumer research. We argue that ecological validity cannot be achieved by simply moving from the internal validity of laboratory settings to the external validity of the natural settings, but that a compromise between them is possible. We assess evidence of how contextual effects should be taken into account and propose a framework to guide experimental choices, composed of four criteria pertaining to the validity of measures: (1) experimental environment, which has been the most thoroughly investigated so far in the literature;

(2) the nature of the product and its presentation (3) the selection of participants and their mindset and, (4) the evaluation task. This framework is used to identify potential critical points in current studies and to discuss the recent methodological developments in sensory and consumer studies. Finally, we draw some research perspectives.

This worked is presented in an article published in the journal Food Quality and Preference

Introduction and background

It is vastly recognized that context impacts consumers' liking and choice of food, with direct implications regarding the validity of measures of the latter obtained in a given context. This issue is key for the food industry, whose strategic choices require reliable models of consumers' liking and behavior in order to predict the commercial success of a product. Yet, the everyday practice of consumer tests appears very heterogeneous regarding the inclusion of context variables, which may contribute to the low reliability of hedonic data used in the industry.

Since Meiselman in 1992 proposed to study real foods in real contexts (Meiselman, 1992), several studies have been conducted in natural consumption settings in an effort to improve the ecological validity of consumer data used in sensory science [START_REF] Bell | Time to eat: The relationship between the number of people eating and meal duration in three lunch settings[END_REF][START_REF] De Castro | Family and friends produce greater social facilitation of food intake than other companions[END_REF]Hetherington, Anderson, Norton, & Newson, 2006;[START_REF] Marshall | Meal construction: Exploring the relationship between eating occasion and location[END_REF]. However, the gain in realism of studies in natural contexts is obtained to the detriment of control over context variables, questioning the reproducibility and transferability of the results.

In the past decades, several approaches have been developed in order to fill the gap between laboratory and natural contexts. They encompass evoked context studies, immersive technologies or the use of virtual reality. These approaches are intended to provide richer contextual realism to standard laboratory approaches by playing on contextual variables such as the physical or social contexts, or by using advanced technology in the case of the virtual reality. However, there are no standardized criteria to determine the type of variable that should or should not be added, and how and when they should be. Therefore, the question of validity and transferability of the data obtained in such conditions remains.

Based on a narrative review, this article discusses the added value of contextual approaches to increase the validity of consumer and sensory data. We argue that the addition of contextual cues in experimental approaches should be based on sufficient experimental evidence gathered within a clear theoretical framework. This review examines the notion of validity and ecological validity through the prism of different experimental disciplines (and particularly consumer psychology and behavioral economics) and draws some implications for sensory and consumer science. We review the recent research on context studies and the effect of context on consumers' liking, choice and intake. We also discuss the use of contextual variables in laboratory settings and the emerging use of new methodologies.

This article sets out to ( 1) define an analytical framework for assessing the relevance of moving towards more ecological validity; (2) assess evidence on how contextual effects should be taken into account in sensory and consumer science studies; and (3) identify the conditions and potential critical points for the design of experiments that take into account context to ensure ecological validity.

The concept of validity in sensory and consumer studies

Evaluating the validity of an experiment: internal, external and ecological validity

The experimental approach is used in various scientific fields concerned with individual behaviors. In particular, consumer psychology and economics use experiments to investigate consumer behaviors and preferences. In these fields, the role of theory in the experimental approach is significant, although not systematic (for a discussion on the role of theory in experimental economics, the reader is directed to [START_REF] Card | The role of theory in field experiments[END_REF]. For instance, experiments in economics aim to either (i) test theoretical assumptions, (ii) generate data on a little known phenomenon or (iii) evaluate the potential impact of policy scenarios or private sector innovations [START_REF] Saulais | Whispering in the ears of… companies? Experimental Economics as a Tool for decision in the private sector [Murmurer à l'oreille... de l'industriel? L'économie expérimentale comme outil d'aide à la décision en entreprise[END_REF]. In consumer psychology, experiments use conceptual models and psychology theories (Kempen et al., 2017;Köster, 2009,) such as the Theory of Planned Behavior or the Expectancy-value theory [START_REF] Ajzen | The theory of planned behavior[END_REF]. While studies in sensory science share this overall goal of better understanding consumer behavior, they often focus on operational objectives, such as to support product development through consumer tests.

In the various scientific fields relating to consumer science, experiments range from controlled, standardized laboratory experiments (standard approach) to natural experiments (experiments run in natural contexts), including different types of field experiments or field data (for more detailed information on field experiments, the reader is directed to the seminal papers by [START_REF] Carpenter | Field experiments in economics: An introduction[END_REF]Harrisson & List, 2004;and to the Fréchette & Schotter, 2015 (Part IV: The Lab and the Field) for a more recent view).

In general, the validity of experimental data is assessed from two complementary perspectives: internal and external validity. While internal validity refers to the ability of experimental data to provide understanding and to explain the causal relations within an experiment, external validity refers to the ability of the results of a given experiment to be generalized to other situations [START_REF] Guala | Experimentation in economics[END_REF][START_REF] Roe | Internal and external validity in economics research: Tradeoffs between experiments, field experiments, natural experiments, and field data[END_REF]. Therefore, moving from controlled to natural experiments implies a tradeoff between these two perspectives.

Ecological validity refers to the representation of the studied stimuli in an environment. This concept was introduced by Egon Brunswik in the area of the psychology of perception [START_REF] Brunswik | Organismic achievement and environmental probability[END_REF][START_REF] Brunswik | Representative design and probabilistic theory in a functional psychology[END_REF]. "Representative design" addresses the ecological validity issue by considering a stimuli representative of the organism-environment relation. Brunswik therefore proposes to move from the study of people to the study of situations, replacing proper sampling of participants with representative sampling of a situation or task; and moving from "artificial" to "natural" contexts [START_REF] Diehl | Ecological validity as a key feature of external validity in research on human development[END_REF]. On the other hand, [START_REF] Brofenbrenner | Toward an Experimental Ecology of Human Development[END_REF] also includes the role of the researcher in the definition of ecological validity. The degree of ecological validity may be determined by the researchers who should ensure that the environment experienced by the subjects has similar properties to the context of interest.

The ecological validity of a study thus depends on whether the task performed in an experimental context is relevant in the context of interest. If a researcher runs an experiment in the context of interest without modifying the ecology of that particular context, the internal validity as well as the ecological validity of that context can be ensured. However, if the researcher runs an experiment in a context that highly differs from the context of interest or has to modify it to establish internal validity, the inferences for ecological validity may not be guaranteed.

This definition of ecological validity generates an ambiguity between the notions of external and ecological validity making it difficult to understand the real purpose of adding ecological value to consumer and sensory studies. Nevertheless, we can assume that a greater ecological validity leads to a greater external validity of the results. Some of the main features of laboratory experiments is the required control over the studied stimuli and the control of the environment in which the experimental study takes place. Laboratory or central location experiments may also allow better control of participants' characteristics (e.g. weigh, hunger state, fasting period…). These factors ensure the ability to explain causal relationships between the stimuli and response. Natural experiments may lack of control over those factors, however they ensure greater ecological validity as natural relationships between the participants and the stimuli occur without restrictions or control of the environment. As an intermediate approach, field experiments attempt to reinforce both internal validity, obtained through strict control over the experimental task, and external validity through the use of a natural physical context, following the rationale that if causality is determined by internal validity, the probability that this relationship (stimuli-response) will be relevant in another ecologically valid setting may increase [START_REF] Roe | Internal and external validity in economics research: Tradeoffs between experiments, field experiments, natural experiments, and field data[END_REF].

These concepts, defined below (Table 1) highlight the importance of three features of an experiment when considering whether it is ecologically valid: the nature of the environment, the nature of the stimuli (in this paper we will refer to the nature of the product) and, the nature of the task. Following the works of experimental economists, we propose to consider an additional criterion: the participants -and more precisely, the nature of the pool of participants and the experience they can bring to the task [START_REF] Carpenter | Field experiments in economics: An introduction[END_REF].

Critical points in sensory and consumer studies

In sensory and consumer sciences, laboratories and central location test (CLT) have long been considered the "gold" standard for the study of consumers' liking and behavior. Those scenarios have offered great reliability and robustness of results due to the control of experimental variables through the application of standards (e.g. the AFNOR V09-500 in France) which establishes a methodological framework to explain causal relations. However, in the last decades, the high rate of market failures of new food products that had been selected on the sole basis of CLT, has prompted researchers and industrials to question the ability of these methodological approaches to provide reliable data [START_REF] Garber | Measuring consumer response to food products[END_REF][START_REF] Jaeger | Future directions in sensory and consumer science: Four perspectives and audience voting[END_REF]Köster & Mojet, 2012).

Using the perspective of the four criteria listed above, we try to identify the main critical points that should be considered when assessing the validity of experimental data in sensory and consumer science.

Experimental environment

Context was defined by Meiselman (2006) as the specific physical, social and situational conditions in which food and beverages are consumed. Several studies have shown that the context in which food is evaluated impacts consumers' liking scores and food choices (Edwards, Meiselman, Edwards, & Lesher, 2003;King, Weber, Meiselman, & Lv, 2004;Meiselman, Johnson, Reeve, & Crouch, 2000;Stroebele & De Castro, 2004). These effects can be seen as a result of the role of context as a whole, or more specifically as a result of the presence or absence of some specific contextual variables in a given setting. These aspects will be more specifically addressed in the next section of the article (Section 3).

Nature of the product

In this review, focus is placed on studies related to food products, although most considerations would also apply to other product categories. In laboratory settings, food products are usually evaluated as single items (bite or dish) and not as part of a meal; even the portion's size is usually smaller than in more natural settings. However, several studies have shown that products evaluated as part of a meal are higher appreciated than individual items (King, Meiselman, Hottenstein, Work, & Cronk, 2007;King et al., 2004). Rozin and Tuorila (1993) have described the concept of "eating reference unit" as the size of the tested food (bite, dish, meal, diet pattern) over time. Each reference unit has a different level of complexity, temporal and spatial importance, and research application. For example, a bite is a unit of reference eaten in a short period of time, in a single space and it is used by sensory and product developers; however, a meal is a unit of reference more complex that includes smaller reference unit as bites and that would be used by food service and institutional researchers (Meiselman, 2006).

However, in studies taking meals into account rather than isolated products, the definition of "meal" is not standardized, as it depends on the researchers' culture and orientations (Meiselman, 2006;Pliner, Bell, Road, Bell, & Meiselman, 2004).

Another critical aspect regarding the ecological validity of the product is its method of preparation. Sensory tests usually employ optimized, standardized cooking methods and minimize variations between batches of products. However, the method of food preparation is involved in the formulation of the hedonic judgement, therefore questioning the ecological validity of the standardized approach (Delarue & Boutrolle, 2010). Several studies have reported a direct effect of preparation methods on liking and discrimination when consumers have the freedom to taste products according to their own habits as they do in natural conditions [START_REF] Matuszewska | Comparison of three procedures for consumer assessment of fat spreads: Short report[END_REF]Posri, Macfie, & Henson, 2001). Variations in preparation methods occur in real life situations, where optimized conditions are rarely met. Yet the standardized tests rarely account for A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 227 the possible impacts of these variations in the data obtained.

Selection of participants

The mindset of participants when performing a study is a key element in the pursuit of ecological validity. Initial beliefs, attitudes, intentions, knowledge and exposure can all have a significant impact on perceptions and decisions, yet they are rarely taken into account in the interpretation of sensory tests (Bernard & Liu, 2017;Boutrolle, Delarue, Köster, Aranz, & Danzart, 2009;Cardello, Bell, & Kramer, 1996;Edwards & Hartwell, 2009;Kempen et al., 2017;[START_REF] Mahon | The role of attitudes, subjective norm, perceived control and habit in the consumption of ready meals and takeaways in Great Britain[END_REF]Tuorila, Palmujoki, Kytö, Törnwall, & Vehkalahti, 2015).

In addition to this, the way participants are involved in the test seems to impact consumers' evaluation. Recent studies have pointed out the motivation and involvement of participants as a critical factor when analyzing and comparing different type of experiments (Bangcuyo et al., 2015;Hathaway & Simons, 2017).

The way the participants are selected and recruited may also constitute an issue. One of the main criticisms made to inferences drawn in sensory and consumer studies has been the use of non-representative populations. This concern is primarily directed to studies conducted for academic purposes, which frequently use student populations. However, this factor only needs to be considered if the mechanisms or tasks involved in a particular behavior depend on the population type. Depending on the research question, specific populations may be required and in this case, the recruitment of the wrong population may compromise the generalization of the results to a more diverse population (Harrisson & List, 2004).

Evaluation task

The features of the experimental task (experimental procedure or instrumental measure) may also have a significant impact on the respondents' behavior -and therefore on the validity of data. The importance of the nature of the evaluation task performed, as well as the psychological processes involved in the task, have been the focus of several studies in the fields of experimental economics and experimental psychology (Harrisson & List, 2004). In sensory and consumers' studies, participants generally answer a questionnaire after tasting a product. The framing of a task, the number and the way of asking the questions have been found to have an impact on consumers' responses (Cardello, 2017;[START_REF] Kwak | Correlation of liking and disliking measurements in consumer acceptance tests[END_REF][START_REF] Kwak | Presentation methods for unidirectional scales to measure consumers' liking and disliking percepts[END_REF]Lim, 2011;Prescott, Lee, & Kim, 2011). Furthermore, some factors such as attention or time perception are known to play a significant role in judgement and decision-making and may directly affect the outcome of a hedonic test or a choice experiment (Dijksterhuis, Smith, van Baaren, & Wigboldus, 2005;Köster, 2003).

Another critical point related to the task is the incentive to reply. The presence of incentives directly associated to an experimental task has been shown to have an impact on the way participants report their willingness to pay for a product. In the absence of an incentive (and even in the presence of a remuneration for their participation), responses tend to exhibit a hypothetical bias, which often manifests in the form of an over-evaluation of the product compared with a consequential task (Carson & Groves, 2007;Shogren, 2005). However, despite its possible implications for new product development, this question has not, to our knowledge, been investigated in the field of hedonic evaluation yet.

Increasing ecological validity: what do context studies say?

From laboratory to natural settings

As a way of addressing the concerns identified in the previous section regarding the validity of such data, it has been suggested to move from controlled settings towards more natural environments -that is to say, to use more contextualized approaches.

Indeed, as an alternative to the laboratory, consumers can be studied in non-standardized, natural consumption environments. The advantage of this field approach is that it reinforces the ecological validity of the experimental setting (environment), allowing researchers to study the interactions between the multiple contextual variables and the consumer's behavior. Regarding the product, while a food product in a laboratory is tested alone and punctually (such as a food product tested as a single dish and presented in a small quantity), the same stimulus in a natural environment (such as a restaurant) may occur in a different, more ecological manner (such as a food product consumed within a meal, in a large quantity). Regarding the task, participants can be unaware of the existence and of the purpose of the study (pure observation of choices or food intake) or be made aware only of some aspects, at the end of the consumption (questionnaires that can be delivered once participants have finished eating or have selected their food) [START_REF] Lin | Restaurant servicescape, service encounter, and perceived congruency on customers' emotions and satisfaction[END_REF].

While adding contextual elements may reinforce ecological validity by nature, we are still not sure about the transferability of the data obtained in natural environments in other contexts -not only because of the environment, but also because the stimulus or product itself and, the features of the task performed are different. In the following subsections, we examine more closely the question of ecological validity of context studies.

Do context parameters play a role in the validity of data?

The way to see ecological validity and its potential effects on consumer judgment has direct methodological implications. In the field of sensory and consumer science, studies looking at the validity of contextualized experiments fall into two categories: those that approach the issue of ecological validity as a whole (the experimental context consist of a combination of the environment and the task performed and, attempts to keep most of them as close to natural as possible) and those that focus on specific factors that are found to have an impact on

Table 1

Definitions and quotes.

The different types of experiments

Laboratory or controlled experiments: "allows underlying causal relations to become manifest at the level of empirical regularities. In a competently performed experiment, single causal connections can be "read off" directly from statistical associations." (Guala, 2012, p. 613) Field experiments: "define what might be better called an ideal experiment, in the sense that one is able to observe a subject in a controlled setting but where the subject does not perceive any of the controls as being unnatural and there is no deception being practiced." (Harrisson & List, 2004, p.1010) Natural experiments: "researcher cannot manipulate the stimulus or influence the data generation process. Rather, the researcher takes advantage of a change in context or setting that occurs for some subjects due to natural causes or social changes beyond the researcher's and subjects' influence" [START_REF] Roe | Internal and external validity in economics research: Tradeoffs between experiments, field experiments, natural experiments, and field data[END_REF], p. 1267) Notions commonly used to evaluate experimental data Validity: "the best available approximation to the truth of a given proposition, inference, or conclusion." [START_REF] Trochim | Introduction to Validity[END_REF] Robustness: "measure of the method's capability to remain unaffected by small, but deliberate variations in method parameters (environment, protocol, laboratory, equipment, staff, …)." (Boutrolle, Arranz, Rogeaux, & Delarue, 2005, p the measures and, try to make these more ecologically valid.

The studies following a global approach compare scores on food liking and choices in different natural environments (restaurants, canteens, prisons) with those obtained on laboratory or central location settings showing differences on hedonic scores (Edwards et al., 2003;King et al., 2004;Meiselman et al., 2000). Those differences are usually related to the degree of discrimination among products -consumers being more discriminant in natural settings than in laboratory settingsor to the higher scores on natural settings versus laboratory settings. The studies focusing on context variables compare how the addition of contextual variables in controlled experiments affect food liking and choice (King et al., 2004;Stroebele & De Castro, 2004;Weber, King, & Meiselman, 2004). We may first notice that several classifications of contextual variables have been proposed: Rozin and Tuorila (1993) divide contextual variables into either product and non-product variables and subdivide them in simultaneous and temporal contextual factors; Meiselman (1996), proposes to distinguish between three categories of variables (the situation, the individual and the product); whereas Stroebele and De Castro (2004), divide the contextual variables into social context variables, physical surroundings, time related characteristics and distraction and/or television viewing. From these studies, it is difficult to fully disentangle the various factors and isolate a specific context effect. The relevance of those contextual variables thus remains unclear. To date, the lack of knowledge of the combined effects of these contextual variables on consumers' responses compromises the ability to identify causal relationships through experimental approaches. In practice, a consequence of this is that participants to a test may not perceive the study context the way the researcher assumes they would. This questions the ecological validity as defined by Brofenbrenner.

The issue seen as a whole would naturally lead to global changes in the test design, while dividing context into separate variables would bring targeted improvements of the experimental setup, keeping the rest of the task and environment potentially non ecological.

Key determinants of ecological validity: a literature review

Methodology

For this literature review, a search on Google Scholar and Science Direct was conducted using the following keywords: 'context'; 'consumption context'; 'social facilitation'; 'food liking'; 'food choice'; 'food intake'. These keywords were used in combination to identify studies on the effect of the contextual factors (context, consumption context, social facilitation) on consumers' evaluation and behaviors (food liking, food choice, food intake). The reference lists and citations of eligible publications were also reviewed to identify pertinent literature.

A criterion for inclusion in the review was that the study had an experimental design in which either food liking, choice or intake was manipulated by a contextual variable (physical, social or food related). Table 2 shows a complete list of all the studies related to context effects following a a) global, b) separated variable and/or c) global and separated variable approach. We analyzed how those studies try to answer to the question of ecological validity by considering the four factors (participant, stimuli as food product, environment and task) previously presented. Twenty articles were identified that met these selection criteria. Of these, the majority (13) measured food acceptability as the dependent variable of interest, whereas nine articles investigated consumers' choice and intake as regards of meal duration and social facilitation.

On the other hand, in the interpretation of the table we also discuss studies that did not meet our inclusion criteria, but which provided additional insight as regards the use of context and ecological validity.

Main results

As can be seen from Table 2, some studies show that context effects on food acceptability differ depending on product categories. Social facilitation shows to increase meal duration as well as food intake whereas food choice seems to increase food acceptability.

Similarities and differences are found when comparing the results from studies following a global approach with those following a separated variable approach. The studies following a global approach study consumer behavior through observation (there is no control over the contexts, products, participants and task) or task modulation. When only observation is used, ecological validity is ensured as consumers behave in their regular basis. In this type of studies, food choice, meal duration and intake can be analyzed, however food perception or liking cannot. When the task is modulated (questionnaire filling, food diary), social facilitation increases food intake and differences in hedonic scores are observed across studies. However, these results are controversial as in some situations no differences were observed (Kozlowska et al., 2003). These studies ensured ecological validity as the contexts, products and participants are not altered, however the transferability of the results into another context should be questioned.

The studies following a separated variable approach modify not just one contextual factor but several factors at a time (for example the nature of the product or the evaluation task) decreasing the internal validity of the results as well as the ecological validity. In this type of studies, the effect of context on product category should be highlighted as differences between snacks and meals ratings are observed, as well as the effect of the use of congruent elements on consumers' liking. This type of studies has also shown controversial results, being significant in some cases and irrelevant in others (Hersleth, Ueland, Allain, & Naes, 2005;Petit & Sieffermann, 2007).

The following parts discuss the outcomes of the literature review regarding the four factors from the previously proposed framework to analyze ecological validity.

Experimental environment

Context has shown to have a certain impact on consumers' liking (Boutrolle, Delarue, Arranz, Rogeaux, & Köster, 2007;De Graaf et al., 2005;Edwards et al., 2003;García-Segovia, Harrington, & Seo, 2015). The experimental environment is the most studied factor in the literature on context. However, the comparison of completely different contexts or the addition of contextual variables have led to controversial results as we have previously indicated. The ecological validity of the results can be compromised due to the use of different participant pool in the case of the global approach (different age, social status, etc.) or to the use of incongruent elements in the case of the separated variable approach (García-Segovia et al., 2015;Petit & Sieffermann, 2007). As shown in Table 2, participants and contexts are confounding elements (i.e. we cannot dissociate both variables) because comparative studies are usually conducted according to a betweengroup design.

Besides, consumers' expectations and beliefs towards specific food consumption contexts play a key role on consumers' judgement (Bernard & Liu, 2017;Köster, 2003). Hence, it must be stressed that comparing laboratory settings to natural consumption contexts may lead to results as different as comparing hedonic scores from two natural contexts (e.g. school canteen and restaurant). Not only the products may differ in both situations, but also consumers' expectations. Unfortunately, participants' expectations are never really taken into account in studies on context even if they could help to explain differences in consumer behavior and hedonic scores.

Nature of the product

Concerning the nature of the product, when the served food sample in a laboratory setting is not representative of the regular amount, preparation and presentation of the same food in a natural setting, it may be hazardous to compare studies because the product/meal combination may not be representative of participants' previous experiences and may convey dissonance and related biases (Rozin & Tuorila, 1993). In fact, we can observe how some products like snacks are able to "pass across contexts" without significant differences on the hedonic scores whereas meals do not (De Graaf et al., 2005;Edwards et al., 2003). This aspect linked to the product category is important to ensure the ecological validity of the results in both global and separated variable approach.

As regards the effect of food combination and sequence of food items during a meal, it is interesting to notice that most of the research on human eating behavior has been focused on food items instead of food combinations. In the last decades, researchers have shown that suitable food combinations result in more pleasant recipes and this is translated in higher overall hedonic scores (Di Monaco, Giacalone, Pepe, Masi, & Cavella, 2014;[START_REF] Elzerman | Consumer acceptance and appropriateness of meat substitutes in a meal context[END_REF][START_REF] Hersleth | Effect of contextual factors on liking for wine-Use of robust design methodology[END_REF]Pagliarini, Gabbiadini, & Ratti, 2005). While others have also studied how much of each meal component contributes to that (Jimenez et al., 2015;Meiselman, 2006). In addition to this, the sequence and appropriateness of mealtimes when evaluating products has produced different results (Boutrolle et al., 2007;Cardello, Schutz, Snow, & Lesher, 2000;King et al., 2004;Meiselman, 2006). Therefore, the study of products as food items instead of part of a meal may contribute to misleading results that cannot be generalized from one context to another.

Another important aspect that has been already mentioned is that consumers and locations are most often confounded variables. They cannot be studied independently as they are intimately related to consumers' expectations and mindset. Even if a food is exactly the same in two different contexts, consumers may not bring to those contexts the same experience, beliefs and/or expectations. As a consequence, even if they like a given food in one context, consumers may prefer another one that fits better another context. Besides, when comparing consumption settings and particularly meals, the preparation method is a key element in the variability of the sensory properties of the product and may be the source of beliefs, that could, in turn, affect hedonic responses (De Graaf et al., 2005;Edwards & Hartwell, 2009).

Selection of participants

In Table 2, we highlighted the following participant-related aspects found in the literature on context: remuneration, group size and relations and, consumers' familiarity. Most of the participants in laboratory settings are recruited on-purpose and compensated whereas participants to natural context studies are not. This aspect can have a strong impact on consumers' implication and therefore, on obtained data. However, remuneration of participants has not been really explored in the literature on context. On the other hand, some of the studies have compared hedonic scores among different contexts were the studied population was too small to generalize their findings (Edwards et al., 2003;[START_REF] Zeinstra | The influence of preparation method on children's liking for vegetables[END_REF]. Moreover, the degree of relation between participants have shown to have different impact on consumers' behavior. When participants know each other they behave in their regular basis whereas when it is not the case, negative correlation with the hedonic scores is obtained (Di Monaco et al., 2014). As regards consumers' familiarity toward the tested products, it must be noted that most of the studies have recruited regular consumers of the tested product. This is an important factor when comparing contexts because some studies have shown that products familiarity may reduce contexts' effects whereas unfamiliar products may be more contextdependent (Giacalone et al., 2015;Hersleth et al., 2005;Kim, Jombart, Valentin, & Kim, 2015). However, we should be very cautious with this notion because in the case of main dishes, familiarity may also be related to particular consumption contexts. , 2003;Meiselman et al., 2000). Besides, we may observe that, even when the task is the same, hedonic scales and questionnaires frequently differ from one experiment to another as well as from one study to another. We also notice important differences in experimental procedures when comparing one context to another. For example, questionnaires are distributed or displayed differently in different contexts (e.g. paper and pencil vs. digital screen). The same goes with the way to ask participants to test the products, etc. It should also be added that tests in laboratory or in central location do not usually account for the fact in natural situations consumers may have the possibility to choose the food they want to eat. This may have important consequences in consumers' mindset, not to mention the product experience itself.

Evaluation task

All in all, the lack of standardization of protocols in the reviewed literature may (at least partly) explain the lack of consistent results as regards the effects of context on consumers' evaluation and behavior.

We argue that ecological validity cannot be seen as independent of internal validity but complementary, and that the focus should be shifted from a search for realism to the definition of clear criteria for transferability from one context to another. Moreover, the focus should be placed on how to isolate the causal effect rather than on the realism from one context to another in order to explain differences among contexts. The pursuit of ecological validity may be seen as a good opportunity to implement the methodologies currently used in the laboratory and try to find a satisfying compromise between the laboratory results and natural setting data.

New methodological approaches: towards increased transferability?

Rolls and Shide (1992) already anticipated the need to bring together the best features of laboratories and natural consumption contexts in order to study the interactions between contextual variables, but in a controlled way. We identify five approaches designed to address the question of ecological validity. The first one, the classical approach, is the use of natural context that we already described in Section 3. The four other approaches are more recent: Living Labs, evoked contexts, immersive contexts and virtual reality. Some of these methods have been described in previous reviews, in particular by Jaeger and Porcherot (2017).

We will first define each type of approach, and then characterize the different studies according to this typology. a) Living labs -Even if a no clear definition for Living labs is found in the literature, the authors have decided to use the definition given by Dell'Era and Landoni (2014) (p. 139) where Living Lab is defined as "a design research methodology aimed at co-creating innovation through the involvement of aware users in a real-life setting". In Living labs, the researcher can control and record a selected number of contextual variables and the interaction between them, within a natural consumption situation. Living lab experiments can be seen as an attempt to compromise with the limitations and advantages of laboratory and field experiments, as the control of contextual variables increases the internal validity of the study, while the situation is kept as ecological as possible. Examples of Living labs dedicated to food studies are "The Restaurant of the Future" Wageningen, Netherlands [START_REF] Hinton | Using photography in 'The Restaur ant of the Future'. A useful way to assess portion selection and plate cleaning[END_REF][START_REF] Zeinstra | The influence of preparation method on children's liking for vegetables[END_REF], "The Grill Room" in Bournemouth, United Kingdom (Bell, Meiselman, Pierson, & Reeve, 1994;Meiselman et al., 2000) and "The Living Lab" at the Research Centre of the Institute Paul Bocuse in Ecully, France [START_REF] Allirot | Effects of a breakfast spread out over time on the food intake at lunch and the hormonal responses in obese men[END_REF][START_REF] Iborra-Bernad | Sensory analysis and observational study in an experimental restaurant: Pilot study[END_REF]. b) Evoked contexts -In the evoked contexts approach, the researcher places the consumer in a typical laboratory evaluation task, but uses either text, audio recordings, and/or pictures that evoke what would be a natural consumption situation of the product (Jaeger & Porcherot , 2017). In this case, consumers have to imagine themselves in a particular situation and evaluate a product or a set of products. This approach is well established in other disciplines such as marketing studies [START_REF] Bitner | Evaluating service encounters: The effects of physical surroundings and employee responses[END_REF][START_REF] Daunt | Unpacking the perceived opportunity to misbehave: The influence of spatio-temporal and social dimensions on consumer misbehavior[END_REF][START_REF] Esmark | I'll be watching you: Shoppers' reactions to perceptions of being watched by employees[END_REF]. c) Immersive contexts -To define immersive contexts, we should first define what immersion means. Immersion is defined by [START_REF] Witmer | Measuring presence in virtual environments -A presence questionaire[END_REF] as "a psychological state characterized by perceiving oneself to be enveloped by, included in, and interacting with an environment that provides a continuous stream of stimuli and experiences". The main difference between immersive and evoked context approaches is that consumers do not have to imagine themselves in a particular consumption situation, but they experience it instead. Three main features describe the characteristics of immersive contexts: lack of awareness of time, loss of awareness of the real world, involvement and a sense of being in the task environment [START_REF] Jennett | Measuring and defining the experience of immersion in games[END_REF]. These approaches usually imply a wealth of means (videos displayed on large screens, multisensory stimulation, including temperature, background sounds, odours, etc.). Within this category, we can also include the recreated environments. Recreated environments are a form of immersive approach where the setting reproduces the physical natural environment where the food consumption would be done, and consumers actually experience a similar situation as in a natural context. d) Virtual reality -Finally, the virtual reality approach is defined by the "use of virtual environments to present digitally recreated real world activities to participants via immersive (head-mounted displays) and non-immersive (2D computer screens) mediums" [START_REF] Parsons | Virtual reality for enhanced ecological validity and experimental control in the clinical, affective and social neurosciences[END_REF]. We argue that including non-immersive mediums such as the 2D computer screen in the virtual reality definition may create certain confusion with the evoked and immersive contexts categories, where such tools can be also used. For this reason, we have considered only virtual reality studies where head-mounted displays are used.

Following these definitions, Table 3 provides an analysis of these four new methodological approaches through the prism of the four criteria of experimental validity that were previously discussed.

Before analyzing each approach, as a general comment, we would like to highlight that the results obtained from each approach may differ depending on the nature of the product (product category) and the familiarity with the product. Certain products may be more affected by situation-specific cues than others. Therefore, special attention should be given to these aspects when analyzing and comparing products evaluations from one context to another.

As it can be seen in the Living Lab studies (Table 3, section a) the characteristics of the participants, the nature of the product and the environment are kept as realistic as possible, whereas the evaluation task through the inclusion of questionnaires may compromise the external validity of the results in a certain way. Consumers experience a natural consumption situation, therefore the transferability of the data to another setting that follows similar patterns can be achieved. However, the use of this type of settings may be costlier and require additional logistics compared to the use of other contextual methodologies.

Concerning the evoked context studies, this approach is easy to apply and inexpensive because not physical elements are added. However, the degree to which participants project themselves to the evoked context is not controlled, despite attempts to measure vividness of evocations, making generalization of results to other contexts difficult (Köster, 2003). Therefore, the gain in ecological validity due to evocation of a consumption situation is difficult to assess, and may very well be outweighed by the loss due to artificiality of the projective task implied by such a procedure.

Immersive approaches have been hypothesized to improve consumers' involvement as well as product discrimination as participants may experience similar psychological processes that in natural contexts (Andersen, Kraus, Ritz, & Bredie, 2018). As it was previously discussed, consumers' experiences and prior beliefs about particular contexts are key elements when conducting sensory evaluations in contexts studies (Köster, 2003). The fact that consumers experience a natural consumption situation even if it is under controlled conditions may ensure the ecological validity of the results and improve the external validity. However, as it can be seen in Table 3 -section c, there is a lack of standardization of the contextual variables in the immersive studies that have been conducted so far, -different degrees of immersion can be shown -therefore there is limited knowledge about the relevance of each contextual variable and their contribution to the outcome of experimental studies. Moreover, the higher costs that these methodologies involve have been highlighted as main drawbacks in their use.

To our knowledge, so far only one published study has attempted to compare immersive and natural settings methodologies. In a study of the impact of context on food evaluation of airplane meals, Holthuysen, Vrijhof, de Wijk, and Kremer (2017) compared overall liking and justabout-right ratings in laboratory, recreated airplane and an actual plane. Recreated and actual plane settings showed similar results, contrary to laboratory settings. However, in this case it should be highlighted that the actual immersive context was a recreated environment. A flight was recreated through the use of a physical environment (cabin creation), use of boarding passes and hand luggage, flight instructions, regular time of flight, etc. Unlike most immersive tests, recreated environments do not place participants in a location where screens, sounds or smells are combined. Further work is therefore needed in the definition and categorization of immersive experiments and on the comparison of external validity between this approach and natural settings.

Finally, an increasingly popular methodological approach to improve the ecological validity is the use of virtual reality. Until now, most of these studies have focused on consumers' purchasing behavior in food stores. This methodological approach has offered controversial results as regards product discrimination and consumer behavior [START_REF] Dreyfuss | In-context consumer research: Benefits and opportunities for immersive techniques[END_REF]. Whereas in some studies similar results have been obtained in virtual and natural environments, in other situations an over effect has been reported. The virtual reality allows participants to place themselves in particular contexts (telepresence) and improve products usability increasing the engagement in the task. However, in some situations, depending on the type of used technology, the use of electronic devices may compromise the "natural" experience and biases the obtained results even if consumers are used to this type of technology. Moreover, the nature of the environment remains non-ecological when 2D computer screens are used as well as the product evaluation task, especially when the research question is related to product acceptability. For further discussion about virtual reality studies, the reader is directed to [START_REF] Stelick | Thinking outside the booth -The eating environment, context and ecological validity in sensory and consumer research[END_REF].

Contribution

Research

Our analysis of context studies in sensory and consumer science considers four critical points when evaluating the need for a given contextual parameter: the experimental environment, the nature of the product, the selection of participants, and the evaluation task. This review adds evidence to the lack of standardized methodologies and analytical framework highlighted by several previous reviews, as well as the problems of robustness and reliability of the results that it induces. We suggest that the use of contextual variables needs to be assessed according to their contribution to ecological, but also internal validity.

There has been a lot of research on the effects of context on consumers' hedonic response, food choice or intake, however the overall inconsistency of findings renders difficult their integration into clear A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 243 guidelines to improve the ecological validity of a study. In particular, to date, the results are too context-specific, product category specific or task specific to enunciate more general principles that could be used to develop such a framework. This has led to the emergence of new methodological approaches, with limited effort to determine how, and whether, each of these methods may complement or outrank the other. This review also highlights that contexts and consumers are confounded variables that make the generalization of the results even more hazardous, as hedonic responses are deeply related to consumers' expectations, which are themselves related to each context.

Therefore, we propose to pursue the ecological validity in sensory and consumer studies from a complementary perspective, in which laboratory and new methodological approaches work together in complementarity. When and how we should consider ecological validity as a goal in research on context should be the most important question. Living labs and immersive studies may be able to reinforce ecological validity when looking at consumers' choice or purchase intention. However, no study has yet examined the external validity of data acquired in such conditions. It is advisable for researchers to plan studies to compare similar methodological approaches (internal comparisons of living labs and immersive studies) across different contexts and different product categories in order to gain better knowledge and understanding of the reliability of the applied methodologies.

In line with the theories of behavioral economics, in particular Prospect Theory (Tversky & Kahneman, 1991), we also propose to give more attention to context-induced reference points when evaluating products. Beliefs (prior experiences) associated to a particular context may indeed play a role by predisposing consumers to a different framework of evaluation. Reference points have been shown to greatly modulate judgement and decision making. Even if very few studies have focused on the effects of context and beliefs on food evaluation, the reference framework of evaluation is likely to be an important factor explaining context effects (Bernard & Liu, 2017;Kempen et al., 2017).

Practical implications

This review has several practical implications. Firstly, we observe that, even though contextual variables have been found to modulate consumer behavior, we cannot establish clear operational recommendations because of the heterogeneity of results found in the literature.

However, this review provides a framework and criteria to assess ecological validity, which could contribute to increase methodological thoroughness in the fields of sensory and consumers' studies, providing workable outcomes to the private sector, notably for product development.

Among all the attempts to improve context, based on our review of the (limited number of) works using recent methodologies, it seems that consumers are more engaged in the task and able to experience a natural context in living lab and immersive approaches. A possible explanation could be that unlike in evoked settings and virtual reality, participants do not have to put too much effort in imagining a consumption situation or use electronic devices which could make the task more ecologically valid. However, this type of experiments can be expensive and difficult to logistically handle, and this conclusion needs to be strengthened by more comparative data.

As regards the nature of the food, it is important to consider, especially in the context of new product development, the type of product that the test aims to evaluate, at which stage of development process the data is needed, and in which settings the final product will be consumed. It has been shown that the impact of context depends on the product category and units of evaluation (e.g. product vs dish). Moreover, familiarity towards the tested product seems to modulate the contexts effects: while a product familiar to consumers can be eaten in several contexts, unfamiliar products can be related to particular occasions and consumption contexts. In the early stages of product development, when specific sensory product characteristics should be defined, laboratory settings should be considered as the best solution. However, when it comes to the choice or purchase intention, more naturalistic environments may be needed to ensure product success.

Although survey institutes and stakeholders in the industry are well aware of the necessity to recruit consumer samples that are representative of a target population, other participant-related factors (the way the participants are recruited and the incentives they receive to take part in the studies) are less considered and yet may also be relevant concerning the validity of hedonic results. Besides, some studies have shown that is important to consider participants' prior experiences, expectations and beliefs when testing a food, as those factors can tell us more about the consumer and the way he/she will behave in a specific context. These aspects are particularly important when evaluating full dishes. In particular, when comparing natural contexts (institutional meals, restaurants, etc.), food preparation has been shown to have a direct impact on the sensory properties of a product and to indirectly influence consumers' evaluation due to the associations made between context and served food.

Finally, as regards the evaluation task, we should consider several aspects. First of all, when comparing contexts, we should ensure that the task and the experimental procedure are the same in order to be able to compare the results. Moreover, it is important to keep in mind, consumers will be more focused on the task performance, therefore on the product itself, in laboratory settings than in the natural consumption settings where the hedonic score can include other aspects such as the actual experience, environment, etc. Therefore, further research is needed to improve the understanding of the effect of experimental procedures and instrumental measures used when comparing settings on the participants' evaluation processes.

Limitations

The lack of homogeneity in the definition and the lack of consistency and standardization in the use of contextual variables and associated tools to measure consumers' behavior may have limited the conclusions that could be drawn from this review.

Another important point is that, although the literature has shown different ways of classifying contextual variables, the relative weight and significance of those variables on consumer behavior need further assessment, especially through replicated studies. Moreover, as it has been shown, several experimental procedures are used through the different studies, thus making it difficult to compare their findings. We suggest that further research should dedicate more attention to the understanding of the nature of the task.

Conclusion & perspectives

Increasing the number of consumer studies in natural settings was pointed as one of the most important challenges for research during the 11th Pangborn Sensory Science Symposium [START_REF] Jaeger | Future directions in sensory and consumer science: Four perspectives and audience voting[END_REF]. In the past decades, sensory and consumer scientists have tried to move from laboratory experiments to natural experiments and different alternative approaches, such as evoked or immersive contexts or virtual reality, have emerged with the purpose of ensuring better ecological validity.

Ecological validity is achieved if participants perceive the experimental environment, the food they taste and the task they perform to be representative of a natural consumption situation.

On the other hand, as [START_REF] Guala | Experimentation in economics[END_REF] proposes, internal validity should be firstly addressed to tackle the problem of external validity. By knowing under which circumstances the results can be extrapolated may allow us to find the specific reasons to explain why results may not be generalized. The problem of external validity might be related to the lack of important factors or the presence of artificial conditions in the experimental design that are far from the natural situations. However, is it important to determine the extent to which those factors can be transferred and reproduced in the laboratory, whether this is always possible, and what is the degree of ecological validity and realism that the researcher should assume and seek depending on the purpose and finality of the study.

Chapter 3. Theoretical framework: Prospect theory I love "churros con chocolate". I really like to have this food for breakfast when I am at home. Now that I am in France, "churros con chocolate" are less easy to find, and when I find a place that serves them, I am a bit disappointed as they do not taste the same as those back at home.

As it was introduced in chapter 1, judgements rely on perception, which can vary depending on the context. This, in turn, can impact reasoning. Therefore, the judgement we elaborate is framed according to a particular situation of evaluation. Likewise, during hedonic evaluation tests, the framing of the evaluation task could affect consumers' perception and therefore, their judgements: this is referred to as framing effects in the field of Psychology. However, when looking at context studies, the task is rarely considered in itself to explain contexts effects. As proposed in the review about the ecological validity of contextual methodologies presented in the previous chapter (Galiñanes Plaza et al., 2019), Prospect Theory (Tversky & Kahneman, 1991) provides a relevant framework to investigate such effects.

In the present chapter, the origins and main principles of prospect theory are introduced. The concepts of framing effects, reference points and loss-aversion are addressed. Then the use of these concepts in the fields of sensory and consumer studies is discussed. The chapter ends with a proposal about the role of consumers' expectations and beliefs about the food offered in the definition of reference points.

Prospect theory

Prospect Theory (PT), introduced in 1979 by Daniel Kahneman and Amos Tversky, proposes a model of judgement and decision-making between different options or prospects, under risk and uncertainty.

The central assumption of this theory is that the outcomes of our decisions are defined by losses versus gains with respect to a reference point instead of absolute and/or final states of wealth (Tversky & Kahneman, 1991).

Prospect theory relies on four principles (Barberis, 2013, p.176):

1. Reference dependence: consumers make decisions according to a reference point 2. Loss aversion: consumers are more sensitive to losses than to gains of the same magnitude as regards that reference point 3. Diminishing sensitivity: bigger changes on the outcomes have a higher impact on consumers' decisions than smaller changes 4. Probabilities weighting: consumers "overweight unlikely extreme outcomes" when making decisions Extrapolating this information to the context of the evaluation task and consumers' hedonic judgement, it could be assumed that framing effects will occur depending on the way the evaluation task (procedures and instrumental measurements) is formulated. The salience of certain characteristics of the product may be modulated, and in turn the reference point from which consumers evaluate the product. Hence, depending on the framing effects of the evaluation task, consumers' hedonic judgement may vary.

Loss-aversion

The principle of loss aversion relies on the observation that consumers are more sensitive to losses than to gains of the same magnitude, with regard to a reference point. Moreover, it considers that losses have a stronger psychological impact on consumers' decision-making which means that consumers are more willing to run the risk to avoid losses than to make gains [START_REF] Jervis | The Implications of Prospect Theory for Human[END_REF]. Figure 5 illustrates this principle by the asymmetric S-shaped value function in which the slope below the reference point is steeper than the slope above the reference point.

Loss-aversion has been also related to the "endowment effect" [START_REF] Kahneman | Anomalies The Endowment Effect , Loss Aversion , and Status Quo Bias[END_REF] which means that when consumers possess something, their sensitivity to losses and gains changes. In an example given by [START_REF] Knetsch | The Endowment Effect and Evidence of Nonreversible Indifference Curves[END_REF], he offers either a mug and a candy to different groups of participants. After a while, he asks the participants with the mug if they would like to exchange it for a candy, and he does the same with the participants with the candy by offering them the possibility to exchange it for a mug. 89% of the participants keep their initial option showing the effect of the initial endowment on the consumers' choice. He also runs a similar experiment in which he asks the participants with the mug to select a price from a list of prices to sell the mug whereas the other group of participants without a mug has to select a price for buying it. In this experiment participants with the mug asked for higher prices to sell (that is to say, to lose their endowment) than the participants without the mug in order to buy it (to gain something).

PART A: Literature review and Research Hypotheses Coming back to product evaluation, when looking at consumers' judgement in natural consumption contexts, the value (either monetary, or hedonic value) that consumers expect to gain from eating in a given context may influence their judgement. In this case, when looking at hedonic evaluations between consumer testing facilities and natural consumption contexts, the consumers' value function could be a key contributor to explain those differences.

Applying prospect theory to sensory and consumer studies

Prospect theory offers a theoretical framework to study and explain the effects of context on consumers' decision-making, through the perspective of effects related more specifically to the framing of the task itself. Although this theory has been used by experimental economists and psychologists in order to explain and predict consumers' decision-making depending on the way a situation is framed [START_REF] Cartwright | Reference dependence and prospect theory[END_REF][START_REF] Jervis | The Implications of Prospect Theory for Human[END_REF][START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF], it has been rarely considered in the field of sensory and consumer science to explain contexts effects in consumer hedonic evaluation.

In the paper "Diversity in the determinants of food choice: A psychological perspective", Köster (2009) argues that little multidisciplinary research is done in the field of sensory and consumer science.

However, solid theoretical principles from disciplines such as psychology could help to explain some of the questions sensory and consumer scientists arises.

Chapter 1 showed how contexts effects are observed in consumer's hedonic judgement at the environmental level (Meiselman, 1992), and at the evaluation task level. Nevertheless, there is not a clear explanation about how those effects may occur and which mechanisms are behind them.

Expectations: confirmations and disconfirmations as gains and losses

Expectations can be defined as "the relationship between the objective stimulus and some pre-existing cognitive basis against which the objective stimulus is judged" (Cardello & Sawyer, 1992, p.254).

This means that any (new) information related to a product is going to create an expectation towards it in the moment of consumption that is going to influence the whole experience of the product, so its judgement. If consumers' expectations are achieved they will be considered as gains; however, if they are not met, they will be considered as losses. Therefore, this can be related to the principle of losses and gains of the prospect theory.

Looking at consumers' hedonic judgements and expectations through the lens of prospect theory, [START_REF] Schifferstein | Asymmetry in the Disconfirmation of Expectations for Natural Yogurt[END_REF] showed an asymmetry on consumers' expectations, explained by the assimilation/contrast theory which follows a similar pattern to the asymmetric S-shaped value function of the prospect theory (Figure 6). The assimilation contrast theory defends that when the differences between what is expected and experienced is relatively small, assimilation will likely occur; however, when the differences between both states increases, contrast effects may be observed (Piqueras-Fiszman & Spence, 2015). Consumers with high expectations who receive an inferior product may perceive it as a ''loss'' whereas those with low expectations who receive a good product may perceive it as a ''gain".

According to this idea, it could be assumed that consumers' expectations may influence consumers' hedonic judgement by the modulation of consumers' reference points. In chapter 1, consumer-related variables such as expectations and beliefs towards a particular product, showed to influence consumers' hedonic judgements. If this influence could be explained by the modulation of consumers' reference point, special attention should be placed on these variables when comparing context studies.

Applying prospect theory to explain contexts effects on consumers' hedonic judgement

Prospect theory lays the foundations to explain the empirical observations about contexts effects on hedonic judgements, and it may allow to further formalize the effects of context to ensure a better reliability of consumer tests.

When I go back home I expect to have the "real churros con chocolate" whereas if I go to a cafeteria in France I do not have the same level of expectations; they are much lower as I do not think they will make the "original" churros. A particular dish such as the "boeuf bourguignon" (a traditional French stew made with beef and red wine from Burgundy, carrots, onions, mushrooms and bacon), is expected to be delicious at a restaurant, whereas the level of expectations may be lower at the university cafeteria or at the hospital; or even at the laboratory where it may be difficult to find something like that.

Therefore, when studying consumers' hedonic judgement in different contexts, (1) the context of consumption and ( 2) the evaluation task of the target product within the context of consumption should be considered.

PART A: Literature review and Research Hypotheses 1. Context of consumption: As it was previously mentioned, consumers' expectations and beliefs have shown to influence consumer's hedonic judgement through the modulation of consumers' reference points. Those references points may be built from consumers' past experiences with a product in a particular context. Therefore, it is important to identify what differ on consumer experience when moving from a context to another, in order to characterize those reference points.

Evaluation task:

Framing effects regarding the way in which a situation is contextualized have shown to influence consumers' perception and in turn, consumers' hedonic judgement.

However, to the author knowledge these effects have not been further investigated in the sensory and consumer science literature when looking at context studies. Hence, special attention should be placed on this new contextual variable to identify differences among consumers' hedonic judgement that may go beyond the actual context of consumption.

The present work proposes to examine the effects of context on consumers' hedonic judgements through the prism of those two levels of context effects. The following chapter (chapter 4) will explain in detail how to do it.

PART A: Literature review and Research Hypotheses

Chapter 4. Problematic and Research Hypotheses

Why aren't products equally appreciated at home, at a restaurant or at a consumer test laboratory?

Is it a matter of context? A matter of product? A matter of the consumers?

Or it is a matter of evaluation task?

The literature reviewed in the first three chapters suggests that context influences consumer's hedonic judgement through different mechanisms implied by several contextual variables (Figure 7). We classified those contextual variables according to the criteria used to define the ecological validity of an experiment. However, how those contextual variables affect consumer hedonic judgement is still unclear as there is no standardization in the way the variables should be used or interpreted. This does not allow inferring underlying mechanisms of the context effects on consumer evaluation. Therefore, to increase the ecological validity of data obtained in consumers' tests, it is essential to understand the conditions under which context affects consumer hedonic evaluation of food products. Regarding the different contextual variables that may affect ecological validity, most studies on context have focused on environmental, product and consumer-related variables ("classical approach").

Those variables could represent the first level of context effects that may influence consumer experience. However, when consumers formulate an explicit hedonic judgement it means that an evaluation task has been performed. Therefore, the evaluation task should be also considered as a key contextual variable, especially in the frame of the present work whose objective is to understand the conditions in which contexts affects consumer hedonic evaluation. In particular, regarding the question of ecological validity of data collected in controlled conditions, it is important to understand if the task performed in a context is representative and relevant in the context of interest.

PART A: Literature review and Research Hypotheses

The literature review, also showed a lack of theoretical framework behind context studies. This makes the role played by context effects in consumer evaluation difficult to understand. Besides, in disciplines such as psychology and behavioral economics, context effects are explored from the perspective of Prospect Theory which considers the effects of context on consumer evaluation through the notion of framing effects and reference points [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF]. Framing effects may indeed explain behavioral differences when a given set of alternative options is differently presented or formulated to the consumers. However, those effects have not been considered in studies on context in the field of sensory and consumer science. This is in spite of studies conducted in controlled conditions reporting that evaluation task formats could affect consumers' hedonic response. In order to address this question, we grounded this work in Prospect Theory.

Once identified the four contextual variables and defined the theoretical framework, we delimitated four main objectives (Figure 8) for the present thesis. They will be addressed successively in the following chapters. For each objective, the specific research hypotheses and experimental design are detailed below. conducted in different contexts and within different conditions. In both studies, we tested the role of information which has been shown in previous studies to influence consumers' beliefs and expectations and to modify consumer hedonic evaluation and behavior [START_REF] Bernard | Do labels that convey minimal, redundant, or no information affect consumer perceptions and willingness to pay?[END_REF][START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Mcfadden | Cognitive biases in the assimilation of scientific information on global warming and genetically modified food q[END_REF]. In effect, priming over a particular product aspect frames consumer evaluation as certain characteristics of the product become more salient. Considering that the context of consumption cannot be disentangled from consumers' expectations and beliefs towards the product experience, information seemed to be a good tool to assess this possible interaction. Moreover, it allowed us to explore if consumers perceived information in the same way depending on the context.

 Chapter 5: aimed at identifying how environmental-related variables would influence consumer hedonic evaluation when product-related variables were standardized (amount of food and presentation). Following a between-subject design, we assessed consumers' hedonic responses in three different contexts (Central Location Test (CLT); evoked context; restaurant). Moreover, different information conditions were tested (blind and informed). The hypotheses formulated were:

 Hypothesis 1: Higher hedonic responses would be observed in the natural (restaurant)

and in evoked context than in standardized testing context.

PART A: Literature review and Research Hypotheses  Hypothesis 2: The information about food preparation would modify the salience of consumers' beliefs and expectations, and therefore, consumer hedonic responses as compared with the blind condition.

 Chapter 6: explored whether consumers considered information about food-related variables when choosing food, and if this information influenced their hedonic evaluation. Consumers responses were obtained during a food event conference in the United Kingdom. Different levels of information were tested during the three days of the event.

Chapter 7: The literature review showed that consumer-related variables such as consumer' beliefs and expectations play a major role in the way consumers perceive and experience a product [START_REF] Delwiche | You eat with your eyes first[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Schifferstein | Consumer expectations for vegetables with typical and atypical colors : The case of carrots[END_REF]. Moreover, those beliefs and expectations may differ depending on the context, modulating consumer experience, perception and hedonic evaluation (Köster, 2003). However, to the author knowledge context studies have not explored how expectations towards a particular context may influence consumer hedonic evaluation even if they have pointed out these consumer-related variables as factors responsible of context differences. Hence, chapter 7 aims to understand if consumer experience is influenced by consumers' representations about food in different consumption contexts.

Additionally, most of studies on context effects comparing controlled and natural consumption contexts have been carried out in the United States, the United Kingdom and Northern European countries. This thesis took place essentially in France, a country that may differ in the way consumers perceive and experience food in different contexts due to its gastronomic culture. Hence, for the purpose of this study, twelve focus groups were performed in two different regions (Paris and Lyon), and with two different groups of population (students and non-students). In regard of the literature review, the following hypotheses were made:

 Hypothesis 1: context-related variables would have a different weight on consumer experience depending on the contexts of consumption.

 Hypothesis 2: consumer-related variables towards different contexts would be intimately related to the served food.

 Hypothesis 3: differences between the two regions would be observed in terms of context and product-related variables due to gastronomic cultural differences.

 Hypothesis 4: differences between the two types of population would be observed in terms of consumer experience due to different consumption habits.

Chapter 8: The literature review has shown that within the context effects, the evaluation task may play a major role on the way consumers evaluate and judge a product. Different hedonic responses PART A: Literature review and Research Hypotheses have been obtained when modifying the evaluation task in controlled conditions. Köster (2003) already highlighted that differences in consumers' hedonic responses could be related to the fact that consumers may differently perceive the product or may differently perceive the task. If it is due to the task, this may be related to a difference in "the understanding the instruction" or to "the use of a different strategy in solving the problem" (Köster, 2003, p.360). However, in the studies looking at context effects, this variable has not raised the same interest as environmental and food-related variables. Therefore, the third objective of the thesis aims to understand if the evaluation task influences consumers' hedonic responses in natural consumption context. Consumers' hedonic responses are usually collected through a global question about the overall liking of a product (synthetic evaluation task), or through a global question followed of a series of product' attributes ratings (analytical evaluation task). Those differences in the formulation of the hedonic evaluation task have shown controversial results regarding differences between hedonic responses (Gacula, Mohan, Faller, Pollack, & Moskowitz, 2008;Prescott et al., 2011). For this purpose, two different evaluation tasks (synthetic and analytical) were performed in different products (bread and pizza) with different degree of culinary preparation (homemade, readymade and mixed of the two) in a university cafeteria.

Consumer hedonic responses were compared between the two tasks and the products. Moreover, the sensitivity to variations of food preparation and task was assessed. According to the literature, the following hypotheses were made:

 Hypothesis 1: when two different formats of the evaluation task (synthetic or analytical) would be presented in natural consumption contexts, larger differences between the hedonic responses of consumers should be found.

 Hypothesis 2: the effect of explicitly asking consumer to rate sensory attributes in a natural consumption context would be even greater for products that involve culinary preparation than for ready-made products.

Chapter 9: Reference dependence is one of the fundamental principles of prospect theory and behavioral economics. This principle posits that consumers make decisions according to a reference point. Reference points are considered as the status quo or current state from which consumers make the evaluation of outcomes [START_REF] Tversky | Advances in Prospect Theory : Cumulative Representation of Uncertainty[END_REF]. Outcomes can be perceived differently if the reference point changes or is manipulated [START_REF] Jervis | The Implications of Prospect Theory for Human[END_REF], through aspirations, expectations, norms, and social comparisons (Tversky & Kahneman, 1991). The present chapter integrates previous results and test hypotheses based on Prospect Theory to explain contextual influences on consumers' food evaluation.

The aims of this chapter is to understand how task-related framing effects modulate consumer hedonic evaluation.

Environmental and product-related variables have shown to influence the way in which consumers perceived a food in a particular context contributing to the creation of reference points that could be 1. Preliminary study: « Hedonic evaluation of Lebanese Tabbouleh in different contexts »

Introduction

The need for a more ecological research has been pointed out as one of the four main challenges for the sensory and consumer science field. In the recent years, different approaches (evoked, immersive, recreated contexts and virtual reality) have been developed in order to increase the ecological validity of context studies and improve the generalization of the results from controlled conditions to natural contexts (Galiñanes Plaza et al., 2019). However, very few studies have compared these approaches to a natural consumption situation (Holthuysen et al., 2017).

The literature review (presented in chapter 2) examined how different contextual methodologies make use of the contextual variables to gain in ecological conditions. Among those methodologies, evoked contexts approach aims at placing the consumers in natural consumption contexts by evoking different situations through audio or video or written scenarios (Jaeger & Porcherot, 2017). This approach has obtained higher hedonic responses than in controlled conditions (Hein, Hamid, Jaeger, & Delahunty, 2012) and in some cases a better discrimination among products (Hersleth, Monteleone, Segtnan, & Naes, 2015). Moreover, it is less expensive than the use of immersive scenarios or virtual reality.

However, it is difficult to control how consumers project themselves in a particular context and how vivid this image last during the evaluation task (Galiñanes Plaza et al., 2019). Moreover, chapter 1

showed that the presence of contextual variables such as the environment, food presentation or consumers' expectations may influence consumers' perception about food and in turn, consumer hedonic evaluation. Hence, it is important to also consider those variables when designing an experiment especially in controlled conditions; that includes evoked contexts.

In order to assess how environmental-related variables influence consumer hedonic evaluation, this study compares consumer hedonic responses of a product (Lebanese Tabbouleh) under three different contexts: central location test (CLT), evoked context and student cafeteria. The evoked context was selected due to logistical facilities.

PART B. Preliminary studies

It was hypothesized that higher hedonic responses would be generally observed in the natural (restaurant) and evoked context (Hypothesis 1).

Moreover, in order to explore the role of product-related variables such as food preparation, this study examines the effect of information about food preparation on consumers' hedonic responses. The literature review showed that food preparation may influence consumer hedonic evaluation when comparing context studies. According to the literature review, the information about food preparation would have an impact on consumers' beliefs and expectations, and therefore, on consumer hedonic responses compare to the blind condition (Hypothesis 2).

Material and methods

Participants

One hundred and fifty-one students (mean age 18.7 ± 2.5) from the Institute Paul Bocuse were recruited and randomly affected to either the CLT study (restaurant) or the evoked study or the restaurant study and within each context, to the informed or the non-informed condition (each condition was tested on a different day). Participants were not financially compensated for their participation, but they were offered a small gift at the end of the study. Inclusion criterion to participate was allergies (no known food allergy).

Products

Participants had to evaluate a Lebanese Tabbouleh, which was a familiar starter served at the school restaurant. For this study, the evaluated product was offered by Bonduelle ® and it was composed of:

Bulgur (35%), (precooked wheat, rehydrated), durum wheat semolina rehydrated (24%), tomatoes (12%), cucumbers, parsley (6%), extra virgin olive oil (3%), onions shallot, rapeseed oil, alcohol vinegar, dehydrated onions, salt, Dijon mustard (water, mustard seeds, alcohol vinegar, salt), natural lemon aroma, cumin. Participants tasted 70 grams of this product as it was the regular amount consumers had at the school restaurant.

Contexts

The three contexts were located at the Institute Paul Bocuse (Figure 1). This offered a logistical advantage but also allowed as to control the population recruited as we assumed participants may have the same level of expectations towards the food served in the different contexts within the frame of the Institute.

1. The CLT study was carried out in a room as a classical control test.

2. The evoked context was conducted in a room and participant used tablets where pictures of the school restaurant were showed to allow participants to imagine themselves in such context while tasting the products. As evoked scenario the following information was given: Square Flaveur was the name of the school restaurant so participants could have a clear and precise image about the type of restaurant were the food would be served.

a. «
Then information about the menu was given following the classical menu student had at this school restaurant.

3. Square Flaveur school restaurant was the last context in which participants evaluate the product. This restaurant was a fast food type restaurant where students had a menu that include a salad, a sandwich and a dessert all served in paper or plastic cutlery. The Lebanese Tabbouleh was a recipe that the chef usually prepared but for the study he used the Bonduelle ® product we gave him. The selection of this product was first validated with the chef in order to ensure that participants did not find huge differences among the two versions:

the homemade one and the readymade.

. Information conditions

Two information conditions were tested in each context. In the blind condition, participants were provided the product with no information about the preparation and origin of the product. In the 1) 2)

3)

PART B. Preliminary studies informed condition, the Lebanese Tabbouleh was presented together with a questionnaire in which it was indicated: « product proposed by our gourmet caterer ». As the Institute Paul Bocuse is a wellknown gastronomy school, the fact of indicate that the product served was "industrial" was not appropriate and after various discussions we opted for the "gourmet caterer" option.

Sessions

The experiment followed a 3 (setting) x 2 (information condition) design. The experimental campaign was conducted over the course of two weeks (one per setting), and sessions were conducted from: 10h30 to 13h30. The regular lunch was from 11h30 to 14h00. The two experimental conditions (blind and informed) were conducted on separate days to avoid confusion and uncontrolled information.

Experimental procedure and evaluation task

In all three experimental conditions, participants were presented the dish in the same way as at the school restaurant. 70g of Lebanese Tabbouleh were served in a white paper cup as usually salads were presented at the school restaurant, together with plastic cutlery, a plastic cup of water and a paper napkin. Participants were asked to rate their level of hunger on a 9-point scale ranging from "not hungry at all" (1) to "extremely hungry" (2); and their liking for the tabbouleh on a 9-point hedonic scale ranging from "I do not like it at all" (1) to "I like it very much" (9).

In the case of the evoked context, after the question about the hunger level, participants were asked to read the information given about the scenario, look at the tablet pictures and then rate their liking.

All responses were collected using a paper form (see Appendix 1).

Data analysis

Mean liking scores for a known product (tabbouleh) and two different information conditions (informed/ non-informed about "gourmet caterer" preparation method) were compared between and within three experimental contexts. Equality of variances was tested using Levene's test. Means were compared using either ANOVA or Student t-test (SPSS v.16, SPSS Statistics, Chicago, I).

Results

Consumer liking scores in blind conditions

In Figure 2 mean liking scores were observed between experimental contexts. There was no overall difference between the liking scores obtained between the three contexts in blind conditions (F (1, 87) = 1.638; p = 0.192). In the CLT context, liking scores were closed to those obtained in evoked context.

However, in evoked context, a higher consensus on liking scores was found among participants. 50%

PART B. Preliminary studies of scores were set between 6.5 and 8. Conversely, participants showed a higher variance of liking scores in the restaurant context. Although not significant, a decrease of liking scores was observed compare to evoked and laboratory contexts.

Effects of information

In Figure 3 mean liking scores were observed between two experimental contexts CLT and restaurant, and conditions. No significant differences were observed between both blind and informed conditions for both CLT (t (53) = 0.875, p = 0.731). and restaurant contexts (t (68) = 1.292, p = 0.472). In the CLT context, the presence of information, slightly decreased the appreciation of the product whereas in the restaurant the presence of information did not make a significant difference in liking scores but on consumers consensus.

Discussion

No significant differences regarding participants liking scores among the three contexts were observed.

Nevertheless, slightly higher liking scores were obtained at CLT and evoked context. Those results differed from those obtained by Meiselman, Johnson, Reeve, & Crouch (2000) where laboratory liking scores were lower than those obtained in restaurant contexts. Moreover, regarding evoked contexts and CLT contexts, no differences in liking scores were neither obtained. Those results are line from the results obtained by Lusk, Hamid, Delahunty, & Jaeger (2015) when liking scores were compared by using a 9-point liking scale. Regarding the studies comparing CLT to new contextual approaches as evoked contexts and, natural contexts, no comparison with previous studies can be made as this was the first study to the authors knowledge that conducted such comparison. Nevertheless, when comparing our results from those of Holthuysen et al. (2017), who compared CLT, recreated context and a natural context, our results did not find any significant differences among contexts whereas they did. This could be explained by the fact that product-related variables such as the amount of served food and the presentation were standardized among contexts and they were kept as similar as participants were used to have in their natural consumption contexts. According to the literature review (chapter 1), those variables have shown to have an impact on consumers' hedonic judgement.

Moreover, regarding the evoked context as previously observed by Hersleth et al., (2015), contextual information conveyed in evoked context may positively impacted consumer evaluation.

PART B. Preliminary studies

Looking at the information conditions, food preparation information showed to have a slight impact on liking scores. This may be related to the lack of given information or wording (gourmet) as well as the low number of participants per condition. Moreover, as both contexts were inscribed in the frame of the Institute Paul Bocuse participants may not have expected to find readymade products in this context. Nevertheless, it could be observed that the presence of information about food preparation tended to increase the consensus among the participants, especially in the case of the natural consumption context. We could then hypothesize that the presence of information may frame consumer evaluation towards a particular characteristic of the product that could be related to consumers' beliefs and expectations, reducing the interaction with other contextual variables such as environmental ones. This aspect will be further investigated in the following chapters.

Conclusion

In evoked context participants showed a higher consensus in hedonic responses than in laboratory and natural consumption contexts. This could be explained by the fact that the amount of served food and the presentation were standardized and presented in a familiar way close the natural consumption situation. However, the hedonic responses obtained in the evoked context were still closer to those obtained in the CLT. This could be related to the fact that in natural consumption contexts there was still a big number of contextual variables that may lack in the evoked and CLT contexts, modulating consumers' hedonic responses.

No significant differences on hedonic responses were observed when information about food preparation was given. However, the low number of participants per conditions as well as the wording used do not allow us to make direct inferences between the presence of information and hedonic responses. Nevertheless, we observed a higher consensus among participants when information was given in the natural consumption context. Additionally, the presence of information elicited that participants questioned certain characteristics of the product and related them to their own expectations. Studies on contextual variables standardization and consumers' expectations regarding food preparation should be performed with a larger number of participants in order to further explore consumer hedonic evaluation among different contexts.

Chapter 6. The impact of food-related information in natural consumption contexts

The previous chapter suggested that information may play a role on consumer hedonic evaluation in natural consumption contexts. However, no clear and conclusive results were obtained. Chapter 1

showed that within the product-related variables, packaging and labelling had an effect on consumer evaluation and decision-making due to the priming on certain characteristics of the product that may impact consumer prior beliefs and expectations, e.g. through health claims or provenance information [START_REF] Asioli | Making sense of the "clean label" trends: A review of consumer food choice behavior and discussion of industry implications[END_REF][START_REF] D'alessandro | Evaluation of wine by expert and novice consumers in the presence of variations in quality, brand and country of origin cues[END_REF]Hersleth et al., 2015;[START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF].

Nevertheless, evidence of those effects in natural consumption contexts is lacking [START_REF] Boyland | Exposure to ' healthy ' fast food meal bundles in television advertisements promotes liking for fast food but not healthier choices in children[END_REF][START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF].

The present chapter examines how consumers' food choices and hedonic evaluation change depending on the type of information displayed on menu card in a natural consumption context. This study aims to gain insights about whether consumers consider food information when choosing food, and if this information influences their hedonic evaluation. Moreover, methodological and logistical difficulties associated with field experiments are reported, and suggestions for potential improvements are drawn for future studies.

The experimental cafe: an exploratory study on consumers' behavior towards

food information in a natural consumption context

Introduction

Food Matters Live is a cross-sector event that brings together different sectors of the food and drink industry in order to enable collaboration and innovation to support a sustainable food landscape for the future. In November 2017, the Center for Food and Hospitality Research of the Institut Paul Bocuse participated in this event performing an exploratory study about consumer behavior and food information.

During this event, different products "free from", "organic" or "vegan" were presented as part of the trends in the food market. In the last decade, consumers have started to be much more interested in this type of products, focusing on food process and information [START_REF] Asioli | Making sense of the "clean label" trends: A review of consumer food choice behavior and discussion of industry implications[END_REF]. Food information has shown to impact consumer hedonic evaluation and behavior as specific characteristics of the product are primed modulating consumers' beliefs and expectations towards it [START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF] [START_REF] Schouteten | The effect of the research setting on the emotional and sensory profiling under blind, expected, and informed conditions: A study on premium and private label yogurt products[END_REF]. Most of these studies, look at the effects of the information presented on packages on liking, choice or willingness to pay. However, there is still a lack regarding those effects on natural consumption contexts such as restaurants or cafeterias where no packaging is used but menus [START_REF] Boyland | Exposure to ' healthy ' fast food meal bundles in television advertisements promotes liking for fast food but not healthier choices in children[END_REF][START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF]. Therefore, the objectives of this exploratory study were (i) to examine the effect of information on food choice and liking and (ii) to analyze the advantages and disadvantages of setting up a study like this in a natural consumption context.

Before the event, an online survey about conference food was sent to the participants to get more insight about consumers' beliefs and expectations towards the food served in this particular context (Conference food). Unfortunately, not enough data were collected to offer any results (15 responses).

During the event, a live experiment on food choice was set up, in partnership with Levy Restaurants and Food Matters Live. During the three days of the experiment, data were collected on the food choices and liking of the Café's customers.

Material and methods

Participants

Conference attendees who voluntarily came to the restaurant during their lunch break were recruited at the checkout counter. They were told that we were conducting a survey as part of a PhD thesis project and if they could fill out a questionnaire on the food that they had freely selected while eating. In total 188 conference attendees (mean age = 39; 72% women) participated in the study.

Products

The menu was created by Levy Restaurants. It was composed of three proteins options (meat, fish and vegetarian options) and five different salad options. Conference attendees could choose between 1 protein dish and 2 or 3 salads.

Context

The Experimental Café (Figure 1) was set in the conference center close to the different conference rooms under the name "Build your own salad". Tables and chairs were set-up so attendees could have their lunch at the café. The food was displayed in a food stand so attendees have an easy access to the food offer.

1.2.4. Experimental design

Information conditions

The information presented on the menu cards at the food stand and tables was slightly modified each day (Figure 2). This modification was highlighted by changing the color of the added descriptors.

Sessions

The experiment was conducted during the three days of the conference and sessions were conducted from: 11h00 to 15h00. Each day a new information condition was presented.

Experimental procedure and evaluation task

Each day attendees who came to the café were received by one of the three volunteers who presented the questionnaire. The questionnaire was divided in two sections (see Appendix 2):

1. First section: attendees were asked to indicate their level of hunger on a 9-point scale ranging from "I am not hungry at all" to "I am very hungry" and answer some sociodemographic questions.

2. Second section: attendees were asked to indicated their options for the protein and salads dishes the had freely selected and rate their liking on a 9-point hedonic scale ranging from "I do not like it at all" to "I like it a lot".

Data analysis

Frequency analysis was conducted to analysis choice results. Mean liking scores for each dish were compared within the three experimental information conditions. Means were compared using either ANOVA (SPSS v.16, SPSS Statistics, Chicago, I).

Overview of the results

The number of conference attendees who came and participated to the Experimental Café varied from day to day: In general, conference attendees choose more the salmon dish than the chicken and Mediterranean tart (Figure 3). 11 participants did not choose the protein option during the conference event.

Figure 3. Distribution of participants (%) per protein dish option and day (D). D1: name of the dish; D2: information about the food preparation method (more appealing description); D3: information of food preparation method + origin + sustainable claim.

Salad dishes choice:

As regards the salad choice, the broccoli and lentils options were the most selected compare to the other dishes (Figure 4). For the salad options participants could choose several salad dishes at a time. 1.3.2. Liking

Protein dishes liking:

The liking scores of the protein dishes slightly decrease during the three days of conference (Figure 5).

However, no significant differences were observed between the days for each protein option: spicy

Discussion

The objectives of this study were to examine the effect of food information on consumers' choice and liking and to analyze the advantages and disadvantages of setting up a study like this in a natural consumption context.

Concerning the effect of information on consumers' choice, we observed that conference attendees did not pay attention to the information presented at the menu cards. When they came to the Experimental Café, conference attendees observed the food and they asked the catering service about it even if the menu cards were displayed on top of the food stand and tables. Therefore, as the results showed, the choice of food may have not been directly related to the given information. As [START_REF] Grunert | Sustainability in the food sector: a consumer behaviour perspective[END_REF] describes, the need for food information not always lead to the perception of it. Consumers tend to select the information they are interested in and ignore the excess of it. In this type of events where attendees do not have a lot of time for lunch, this may have led them to simplify their food decisions by directly asking the catering service. Additionally, we should consider that conference attendees may have varied their choices within the 3 days of conference to avoid monotony (Köster, 2009; PART B. Preliminary studies Meiselman, 2006). Moreover, it is important to consider that the level of information change for all the dishes every day so this may difficult to disentangle the effect of information on the choice of a specific dish.

Overall the food offer was positively perceived apart from the fact that the dishes were cold and attendees expected to be warm. Looking at the liking scores we should consider that as conference attendees evaluated the food while eating, even if we asked consumers to rate individually each component of the dish, the fact of having a complete meal may have influence the liking scores of some of the meal components as previous studies have shown [START_REF] Elzerman | Appropriateness, acceptance and sensory preferences based on visual information: A web-based survey on meat substitutes in a meal context[END_REF]Jimenez et al., 2015) As occurs with the food choice and monotony, a lack in food variety can be translated in a decreased of the liking scores (Edwards & Hartwell, 2009;[START_REF] Meiselman | The effects of variety and monotony on food acceptance and intake at a midday meal[END_REF]. We observed this effect on the liking scores of the protein dishes which slightly decreased from day to day.

However, this effect did not occur in the case of the salad dishes where the liking scores followed a different pattern. Those effects can be related to the number of participants per day and choice.

Conversely, significant results were obtained for two of the five different salads when longer descriptions about the dishes were presented (information of food preparation method + origin + sustainable claim). No clear explanation for such results can be found further than the monotony conference attendees may have perceived. Origin and sustainability have shown to have a positive impact on consumer hedonic evaluation [START_REF] Hoogland | Food and sustainability: Do consumers recognize, understand and value on-package information on production standards[END_REF]; nevertheless, this is related to personal values that in this study we could not assess. Besides, as the number of participants differed each day and for each choice it is difficult to may inferences related to that.

Concerning the advantages and disadvantages of setting up a study like this, it is important to highlight different aspects that may occur in natural consumption contexts. During the study, the catering service changed the cutlery from day one (wood) to day two and three (plastic). This may have an effect on participants' behavior and especially on liking (Piqueras-Fiszman et al., 2012). Moreover, participants aroused several concerns regarding the sustainability of the plastic cutlery as it was one of the key elements of the event and did not match with the concept of the Experimental Café.

Additionally, the service of the food also varied from day to day -some of the food options were available before others due to some logistical issues in the kitchenwhich may have affected the results regarding the food choices.

An additional element that we did not consider was that participants seemed to be surprised about the price of the menu because getting just one dish (one protein and not salad) had the same cost than get PART B. Preliminary studies 3 dishes (protein + 2 salads) which may also have impact in the choice and liking of the dishes.

Concerning the food offer, snacks (chocolate bars, chips) were also part of the offer at the Experimental Café. We noticed that a lot of consumers just grabbed a coffee and a snack instead of looking at the menu card (on which the experiment was focusing).

Regarding the experiment itself, it seemed that people were not fully able to realize that an experiment was going on, despite the logos and information on the site. Most of the attendees thought it was a commercial questionnaire related to the served food and unfortunately, we did not get many participants, especially on the third day where the numbers dropped quite significantly.

Conclusion

This exploratory study gave us some insights about how consumers behave in natural consumption contexts and how feasible an experiment of those characteristics entails.

In general, conference attendees did not pay attention to the presence of information on the menu cards. They were more focused on the appearance of the food when choosing their menu and, other contextual elements such as the cutlery used when evaluating the food than on the information provided. From this result, we can conclude that much more effort should be put on the way food information is presented in natural contexts. Besides, we should consider that depending on the type of setting, cafeterias or restaurant, consumers may behave in a different manner so the way to communicate about food should also differ.

Experiments in natural consumption contexts allow us to better understand consumer behavior and get direct feedback from the consumers. However, several factors external to the experiment (problems in the service of the food or the used cutlery) may occur biasing or making difficult the analysis of the results. Therefore, we suggest that an equal commitment between the internal validity of an experiment in controlled settings and the external validity of an experiment in natural settings should be found.

Conclusions PART B

Part B presented two preliminary studies that have helped to define some of the research and methodological questions related to the set-up of context studies in natural consumption contexts. The first chapter aimed at identifying the effects of environmental-related variables on consumer hedonic evaluation when product-related variables were standardized. Results showed that the standardization of the amount of served food and the food presentation among contexts (evoked, CLT and natural consumption contexts) -close to the presentation in the natural consumption situationmay have helped consumers to experience a similar eating situation reducing the differences between consumers' hedonic responses. Moreover, the presence of information about food preparation increased the consensus among participants in the natural consumption context (restaurant). The role of food-related information could be an interesting approach to focus consumers' attention to product characteristics in natural contexts as it occurs in controlled conditions. The presence of information could minimize the effect of other environmental-related variables on consumer hedonic evaluation.

The second chapter examined consumer decision-making and hedonic evaluation when different foodrelated information was displayed on a menu card in a natural consumption context (conference). The results of this study revealed that consumers did not pay special attention to the information given about food. They were more focused on the visual characteristics of the menu. This could mean that depending on the consumption context and situation, consumers may pay more or less attention to certain characteristics of the product. Then, when studying the effect of information on consumer hedonic evaluation, better ways to present such information should be explored if we expect to compare context studies.

From a methodological point of view, different aspects were underlined as a result of these two studies:

1.

Environmental-related variables:

 These two preliminary studies have shown that there is a clear difference in consumer behavior when consumers are in a school restaurant and when they are in a conference restaurant. The foodservice differs, the environment differs, the population differs, so all those elements are going to influence the way in which consumers interact with the food, perceive it and judge it. Hence, when comparing context studies, it is important to consider not just the physical situation but the actual behavior consumers have in those contexts and what they actually experience.

PART B. Preliminary studies

Product-related variables:

 The first study showed that present food as close as it is presented in the natural consumption context could help consumers to project themselves eating that food in a particular context.

 The first study showed that it is important to pay attention to the eating reference unit that should be compare: snack, raw ingredient (apple) or a dish. Preparation, storage and presentation of dishes require much more control when comparing context studies that snack or raw ingredients. Moreover, the second study showed that liking scores of meal components may be influenced by the presence of other meal components. Therefore, it is suggested to work with dishes that included several ingredients but in a product as a whole like multicomponent dishes: quiche, cakes, pizzas, etc. instead of chicken with potatoes and salad, fish and chips, etc.

 These two preliminary studies showed different results with regards to the presence of information. Consumers may not pay the same attention to food characteristics at a restaurant, conference or CLT. Hence, it is important to identify the best way to present food information depending on the context.

Consumer-related variables:

 In the first study participants discussed if the dish presented was made by the chef or not, mentioning words such as: industrial or homemade. Consumers' expectations about food and its preparation may be relevant when evaluating dishes in different contexts. Hence, special attention should be put on this variable in order to gain more insights about consumers' mindset when comparing contexts.

Consumer-related variables:

 Regarding the studied variable, both studies showed that liking may not be able to explain by itself the differences or not among consumers' hedonic responses when looking at context studies. Instead, consumers' expectations and beliefs' towards the food served in those different contexts may offer more insights about the possible differences found when comparing context studies.

The following chapters will integrate and further explore those insights.

Chapter 7. Consumers' mindset on consumption contexts 1. Introduction

This thesis aims at understanding the conditions under which context affects consumer evaluation of food products. The literature review (chapter 1) has shown that consumer-related variables such as consumers' beliefs and expectations play a major role in the way consumers' perceive and experience a product [START_REF] Delwiche | You eat with your eyes first[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Schifferstein | Consumer expectations for vegetables with typical and atypical colors : The case of carrots[END_REF]. Moreover, those beliefs and expectations towards a particular product may change depending on the context, modulating consumers' experiences and thus, product evaluation (Köster, 2003).

If we look at the pictures presented below (Figure 9), we may be able to identify different contexts of consumption and within each context, a particular environment and type of food. This may be related to our past experiences within those contexts or to the beliefs and expectations those contexts may elicited. gastronomic culture and history that may influence in a different way how consumers perceive food in different contexts (Corbeau, 1992;Fischler & Masson, 2008). Therefore, this difference arises the PART C. Consumer-related variables need to explore how French consumers perceive and experience food in different contexts.

To achieve the objective of the present chapter, a qualitative study was conducted to obtain a large information about consumers' representations of food in different consumption contexts. Twelve focus groups were performed in two different regions, Paris and Lyon, with two different groups of population, students and non-students. Focus groups allow to collect more information than individual interviews as participants interact during the discussion sharing opinions and thoughts. Besides, the decision to compare two regions and two different type of populations allowed us to observe possible differences in the way consumers integrate contextual variables in their meal experience due to cultural differences related to gastronomy (Lyonnais cuisine versus a more global French cuisine); and due to consumption habits (students and non-students).

Questions were developed based on the literature review. The following topics were defined: food experiences in different contexts, contexts and food preparation and, food preparation and culinary skills. A focus group guideline (see Appendix 3) was implemented together with French colleagues from social sciences in order to set the right open-ended questions to avoid the possibility to get a yes/no responses. Moreover, basic principles regarding the role of the moderator were also examined [START_REF] Lawless | Qualitative Consumer Research Methods[END_REF].

Regarding the literature review the following hypothesis were formulated:

Introduction

French consumers and their gastronomy are well known since the XVIII century. French cuisine is characterized by its "savoir-faire", "gourmandize" and pleasure (Fischler & Masson, 2008). Food rituals have been widely investigated in disciplines such as sociology and anthropology underlining characteristics of the French meals such as the conviviality, and the structured organization of a meal (Corbeau, 1992). Nevertheless, in the last decade changes in those rituals have been observed due to the lack of time for cooking and eating, and the multiple options foodservices propose (GIRA Conseil, 2013).

The wide offer of eating out contexts such as brasseries, bistros, gastronomic restaurants or fast food restaurants, is associated to different consumer experiences. Experiences that differ when consumers go to eat at the workplace cafeteria or at the school cafeterias due to the differences in the food ritual followed by the consumers (Corbeau, 1992). Those differences in meal experiences may be constructed from different factors, such as contextual variables that may entail differences in the way consumers perceived a particular consumption context and the food served in it (Edwards, 2013).

Contextual variables such as the physical context of a restaurant, the environment or the food served have been found to influence consumers' food perception so in turn, consumer experience and hedonic evaluation (King, Meiselman, Hottenstein, Work, & Cronk, 2007;[START_REF] Meiselman | Demonstrations of the influence of the eating environment on food acceptance[END_REF]Timothy, Yang, & Kim, 2016). When comparing context studies, differences are found regarding consumer hedonic evaluation of a product or a dish depending on the context (Boutrolle, Delarue, Arranz, Rogeaux, & Köster, 2007;De Graaf et al., 2005). This could be explained by the fact that consumer experience changes due to the presence of different contextual variables from one context to another as well as consumers' beliefs and expectations towards that particular context.

Factors such as consumers' beliefs and expectations towards a particular context have been associated

to differences in consumers' food perception and a posteriori evaluation (Köster, 2003(Köster, , 2009)).

Moreover, those consumer-related variables have shown to influence consumer experience as well [START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF]Michel, Velasco, Gatti, & Spence, 2014). Do consumers' beliefs and expectations differ towards different consumption contexts, and if so, are those differences related to the food served in that particular context? Studies have highlighted "food attributes" (ingredients, tastiness, variety and quality) as key factors when consumers select to eat out in a particular restaurant (Ozdemir & Caliskan, 2014;Timothy, Yang, & Kim, 2016). Hence, it could be hypothesized that consumers' beliefs and expectations towards a gastronomic restaurant may be based on product-related variables such as taste, quality and presentation; whereas in a workplace cafeteria, contextual-related variables such as the environment may lead consumers' expectations and in turn, consumer experience.

This study aims at understanding how consumers' representations about food in different consumption contexts may influence consumer experience and therefore, their hedonic evaluation. To do so, a qualitative study was conducted within two different regions (Paris (n = 6) and Lyon (n = 6), and two PART C. Consumer-related variables types of population students (n = 6) and non-students (n = 6). These two different regions were chosen in order to explore gastronomic differences within a country that may influence consumers' meal experience and consumer evaluation of food in different contexts (Fischler & Masson, 2008).

Moreover, the two types of population were selected to further investigate context's effects on nonstudents' population (30-60 years old). Most of context studies are conducted within student's population (18-25 years old) who may have different criteria when it comes to meal experience evaluation [START_REF] Urdapilleta | Culinary choices: A sociopsychological perspective based on the concept of Distance to the Object[END_REF].

We hypothesize that (i) context-related variables would have a different weight on consumer experience depending on the contexts and (ii) consumer-related variables towards different contexts would be intimately related to the served food. Moreover, (iii) differences between the two regions would be observed in terms of context and product-related variables due to gastronomic differences and (iv) differences between the two types of population would be observed in terms of consumer experience.

Methods

Consumers

Consumers were recruited from two consumers' databases: in Lyon, the Institut Paul Bocuse Center for Research and Hospitality, and in Paris, a market research agency. Twelve focus groups were conducted with a total of eighty-six French consumers. Table 1 shows the socio-demographic characteristics of the consumers. Six focus groups of non-students (n=41, mean age = 49) and six focus groups of students (n=45, mean age = 22) were conducted in Lyon (n=33) and in Paris (n=53)

(three groups of each type of population per region). At recruitment stage, no information about the specific aim of the study was provided. Consumers were just informed about the duration of the discussion (between one hour and a half and two hours), the general topic (food consumption) and the remuneration they would get. Data were collected between May 2017 and November 2018. 28.6% G: refers to the focus group and the numbers (1, 2, 3, etc.) to the group session.

Focus groups

Consumers were involved in a semi-structured discussion about their eating out habits and food representations at different consumption contexts.

Each session included from 5 to 10 consumers, for a total of 12 sessions conducted. Each session lasted for about one hour and a half to two hours.

Sessions followed a pre-defined guideline structured as follows: All focus groups were led by the same moderator who verified if the different topics set in the session guideline had been addressed.

Data analysis

All focus groups sessions were audio-recorded, and subsequently compiled and transcribed. Two complementary analyses were conducted to understand how consumers' representations about food in different consumption contexts may influence consumer experience:

1. A thematic analysis [START_REF] Braun | Using thematic analysis in psychology[END_REF]: the corpus of each session was (i) vertically analyzed to identify the themes discussed within each session by each participant, and (ii) horizontally analyzed to identify how the themes were discussed within each session by all consumers. A horizontal comparison between the twelve focus groups sessions was then conducted to define the main themes.

2.

A lexicometric analysis: this analysis aimed to identify the main differences in terms of discourse between the two main variables: the location (Lyon and Paris) and the type of groups (students and non-students) among the twelve groups (G) [START_REF] Dransfield | The application of a text clustering statistical analysis to aid the interpretation of focus group interviews[END_REF]. This method is designed to analyze the lexical organization and association of the words used by the consumers and its semantic mapping [START_REF] Cerisier | Reproduction sérielle d ' un matériau odorant : de l ' odeur sentie à la reconstruction collective de son souvenir[END_REF]. To perform this analysis, each focus group session was coded and analyzed using iRaMuTeQ -a R interface for multidimensional text analysis and questionnaires -(iRraMuTeQ 0.7 alpha 2, © 2008-2014 Pierre Ratinaud). This software: a. Segmented the corpus using the punctuation marks presented in the corpus -in our case each segment was a line break -and coded the words using an internal dictionary (adjectives, verbs, nouns, etc.) PART C. Consumer-related variables b. Reduced the words to their roots forms (Lemmatisation): verbs to the infinitive, nouns to singular, etc. c. Analyzed the text through: correspondence analysis (CA) to identify the words opposition and associations; top-down hierarchical cluster analysis (Reinert method (Reinert, 1983) to define the main themes.

Data from the questionnaire about eating out habits (Table 1) were analyzed using (XLSTAT Addinsoft (2019), statistical and data analysis solution. Paris, France).

All the analyses were performed in French and the final analyses were translated into an English version. Only the correspondence analysis is presented in French.

Results

Pictures classification

From the twelve focus group, a total of thirty-three subgroups (SG) of two and three consumers were randomly created and asked to sort the pictures of the different eating locations. Table 2 shows the criteria used by the consumers to categorize the pictures from most to least cited: As it can be observed 14 subgroups used elements of the physical context to sort the pictures, whereas just 1 subgroup sorted them by type of served food.

Thematic analysis

Six themes emerged from the thematic analysis: consumers' attitudes towards different food consumption contexts, consumers' attitudes towards food ingredients and processes, affective experiences, sensory experiences, knowledge experience and consumption habits. A detailed PART C. Consumer-related variables presentation of each theme is provided in the following sections.

Consumers' attitudes towards different food consumption contexts

The game of picture classification led participants to express what the different contexts evoked in terms of environment and served food. In general, all contexts aroused both positive and negative attitudes that differed in some contexts depending on the location (Lyon and Paris) and group (nonstudents and students). Table 3 presents the main differences among consumers' attitudes regarding three main criteria: physical context, price and menu's variety.

Past experiences helped consumers to describe their positive and negative attitudes towards contexts.

The physical context had an important impact on consumers' attitudes when it comes to eating out at different contexts, especially for those from Paris. Within the physical contexts consumers discussed about the influence decoration and hygiene have on the way they perceived a particular context. The price was also relevant, especially for the students' groups that show positive attitudes towards fast food restaurants even if the quality was not as expected but the price was affordable. Conversely, the non-students' groups focused on the quality/price ratio showing negative attitudes towards fast food restaurants and in some cases towards brasseries and bistros. Another aspect that contributed to the positive or negative attitudes towards the contexts was the variety of the menu and the number of dishes presented on it, especially for the groups of students, mainly for those from Paris. Consumers highlighted the lack of variety on school or workplace cafeterias.

Consumers' attitudes towards food ingredients and processes

Together with the attitudes towards consumption contexts, consumers widely discussed about the food served in different contexts. Consumers associated the use of certain ingredients and processes to different degrees of food quality: "Food products are never the same in a restaurant, in a canteen ...As part of a study maybe, but in the daily basis no." (woman, G2). Consumers agreed that depending on the prize of the menu, it is possible to determine the quality of the served food in a particular context as it was previously described.

Table 4 shows consumers' attitudes towards food in different consumption contexts by looking at five different criteria: food price, quality and context; homemade and industrial products; their uses in different consumption contexts and their origin and traceability.

Consumers made an important difference between two groups of products and processes: homemade products related to fresh, tasty and local ingredients and, industrial products and processes related to additives, chemicals and public scandals. Consumers associated the use of those types of products to different contexts of consumption. In general, all consumers agreed that attitudes towards food ingredients differed depending on the consumption situation, being the consumers from Lyon, especially the non-students one the most demanding in terms of the use of fresh and local ingredients.  "I think that when we go to the cafeteria and we pay 3 euros, we will not have a blue cheese sauce as stylist as the one we can find in a restaurant." (woman, G4) (+) ratio food quality/price: highlighted by non-students' groups. They agreed that some efforts have been done and that depending on the workplace cafeteria and the company the quality could be ok.

PART C. Consumer-related variables

 "I believe that the workplace cafeterias are related to the prestige of the society too, so a higher effort is done" highlighted by all groups. The recent scandals food industry has gone through made all groups shared negative attitudes towards those products and processes.

(man, G6) (

 "We have less confidence in the food industry because we do not see what is really inside the products… When products are already packaged, we do not know what have happened before"

(man, G11)

 "Too many scandals, too much chemicals, we do not know what they put in the end: the flavor enhancers, the salt ... Today we are in the excess of the chemical, of the artificial, so we move completely away from the homemade" (woman, G2) PART C. Consumer-related variables (-) frozen, vacuum and canned processes. Highlighted by all groups due to the use of additives, flavor enhancers, and colorants etc. Associated to a lower taste compared to homemade products.

 "There is the chemical used to make chemical reactions to have a particular result like gelatin, and there are all the chemical stuff that are used to preserve the vegetables, to make them prettier, additives or flavor enhancers because the classic taste is not appreciated, etc."

(man, G12)
Use of products in different food consumption contexts (-) Industrial products and processes: highlighted by most of the groups due to the amount of food should be prepare and the timing  "At the cafeteria food is made with vacuum or frozen products, so you cannot have the same taste that a product that is fresh, that comes from the market. Something that is already transformed and that has been waiting for days and days in vacuum bags, it cannot have the same taste as a product that has been just harvest…"

(man, G2) (-) Industrial product and processes: highlighted by the groups from Paris.

  "It's the quality of the original foods that makes the difference. You can have a food truck where everything is bought at the market, the meat of the farmer of the corner and another food truck where all products are bought in Auchan, Leclerc, the retailor brand so you are going to have two food trucks, the same menu, except that the food will not have the same quality"

(man, G2)

(+) consumers' trust:

highlighted by the students' groups from Paris. They argued that in some cases they trust more the industry when everything is well specifying in the label, than certain products from the market where no information is given.

 "I can trust the small producer if it is clear regarding the transformation of his products, but I can also trust the industrial if the products have been well followed. For me, traceability counts" (woman, G11)

PART C. Consumer-related variables

Affective experiences

The affective experience refers to the emotions evoked when eating out in different contexts.

Consumers agreed that different contexts provoke different feelings depending on the environment, company and food. "If I go to the restaurant with my boyfriend, we will take a bottle of wine and we will have fun because we are both of us and we will enjoy this moment. While when we go with friends, we will go to a pizzeria, something a little cheaper in price, because the conviviality is more important than the quality, it is a moment of sharing with friends!" (woman, G2)

Conviviality and warmth environments were highlighted as key variables to enjoy a particular food experience. Consumers, especially those from Lyon and the groups of students insisted on it.

Nevertheless, in the case of the gastronomic restaurants, the conviviality was not evoked in terms of affective experiences but the food did (Table 5).

Sensory experience

a. Flavor: In general, all consumers considered the flavor as a key factor of the food experience when eating out independently of the context. However, they agreed about the fact of being less demanding about it at workplace cafeterias or at the hospitals; and they related this to their lower level of expectations. Moreover, the group of non-students insisted more about the importance of the flavor than the students' groups. Both, non-students from Lyon and Paris, considered the flavor as a synonym of the quality of the food and they associated it to the term "authenticity". "Have you seen Ratatouille? when he closes his eyes, there is an explosion of colors, so for me cooking is that! you must be greedy, it must be an explosion where each taste is a note of color!" (man, G9); "Today we are looking for the taste, the authenticity of the taste of the product. If carrots smell like strawberries there is something wrong, either cooked or raw carrot must taste like carrot." (man, G2).

b. Presentation: Visual aspects were also highlighted, especially when eating at gastronomic restaurants. In general consumers (mainly those from Paris) underlined the importance of the presentation as a potential attractor to consume a particular dish. "It is like at home. At home when you make to yourself a great dish and it is beautiful you enjoy it a lot. If you put the leftovers in a tapper, and you eat it the day after, it would be less good. That's because of the visual." (man, G11) c. Texture: it was also mention by the consumers, especially from the groups of non-students.

Ingredients such as meat, fish and vegetables were the object of most of the discussions, especially for those dishes prepared at workplace cafeterias. "In dishes with a long cooking, the frozen vegetables will become a paste if they are not good, in addition to losing their vitamins and their taste, they will not even have a beautiful texture. So for this kind of dishes, we have to use real vegetables, to ensure the taste and texture" (man, G8). the homemade definition, certain differences where observed between non-students and students' groups, being the latter less demanding about what the homemade definition entails. However, for the industrial product and process definition, there was a consensus among all the groups. Moreover, consumers related both concepts to different degrees of quality. a. Homemade: In general, homemade was defined as "something done from A to Z. I expect a certain standard in terms of quality of raw materials. It's not taking all the time the eggs, the flour, the milk at first price. If you do things with fruits, you use seasonal fruits, local. And the person who does it, does everything, buys them, prepares the dough, cooked, etc." (woman, G5). However, some consumers underlined that there was a controversy about the use of the term: "There is an administrative nuance. It is said that when the products arrive and are assembled in the kitchen or at the lab they can be also considered as a homemade product" (woman, G2). b. Industrial: consumers described industrial products and industrial feeding as "… transformed, canned products" (man, G2); "They are the frozen products" (woman, G7); "Industrial feeding are fast foods, self-service, catering and cafeterias usually associated with junk food." (woman, G9). c. Quality: consumers associated those type of products and processes to the definition of quality; more specifically they associated homemade products to a higher quality whereas the industrial products to a lower quality: "It's the fact of having homemade products, fresh products, with a chef behind, even if it's not a super chef, but who knows how to do the right dishes and not just the industrial reheating like plenty of restaurants in Paris do." (man, G8). Moreover, the term quality was also associated to the flavor of ingredients, the pleasure and the sensory experience, especially for the groups from Lyon "In fact if we remember what we ate, it means that it was good! The quality was there, there was the homemade behind! There is the pleasure, it is a tasty experience!" (man, G2). Moreover, consumers associated those terms to the logistics of certain consumption contexts and the level of training of the chefs: a. Contexts association: all groups associated the use of industrial products and processes to big consumption contexts such as fast food chains, cafeterias, or hospitals, due to the large volume of meals served. "We wanted to eat at the cafeteria because the chef prepared for 80 people.

PART C. Consumer-related variables

You saw the trucks of fruits and vegetables arrived and it was super good. Then, 300 new employees arrived and everything change. We switched to processed food, to go fast. So no more the same cooking and staple foods." (woman G9). Another interesting aspect highlighted by the consumers was their knowledge about consumer tests.

Most of the consumers (specially students) did not know what was exactly done in those contexts but some others (especially non-students) already had an idea about what are the objectives of those tests and how they actually work. "There is either food or drink, and we compare 3 or 4 samples of the same product from different brands or suppliers, and that allows us to compare the same product. It is good to realize that within food manufacturers there are differences among the same product." (man, G8).

Consumption habits

Consumption habits were mainly related to culinary skills, the use of products at home and the eating occasions. Some differences were observed in terms of gender and between groups. a. Culinary skills: consumers, especially non-students' women from Lyon, discussed about the importance of cooking and the influence that this action has on the level of expectations and demands when eating in different contexts. "I cook a lot at home, fresh for what I can. So if I go to the restaurant, I want the same quality or better. We also know how to judge a product."

(woman, G1). b. Products: consumers, especially those from Paris, reported to use industrial products at home even if they expressed negative attitudes towards them. The group of non-students argued that due to time constrains, this type of products is more convenient as family dinners can be prepared in a short period of time; whereas for the group of students there was also a question of price. "There are certain products or vegetables that are well frozen. I use them from time to time and that's good. And sometimes we do not even have time to prepare so they are convenient" (woman, G9). Conversely, all c agreed that they did not want to have those type of products at a restaurant because they consider the fact of go out to eat a special occasion: (woman, G3). Students, especially those from Paris, reported to go to the fast foods or bakeries at lunch break even if their attitudes towards this type of food were negative: "It depends. Either I prepare the lunch the night before, or I go to a fast food, or sandwich bar" (man, G10); "We go to the bakery to grab sandwiches before going to class." (woman G11).

They associated this type of contexts as convenience when they do not have time to eat or to prepare at home.

Lexicometric analyses

The software was able to analyze the 95.95% of the segmented corpus as expressions like "wow", "ehhh", "mmm" were not recognized. A correspondence analysis together with a top-down hierarchical cluster analysis was conducted giving as a result five different clusters. Figure 1 shows the associations and oppositions of the words used by the consumers and that contributed to the creation of the five clusters.

We can observe in Table 4 that 56.1% of the analyzed segments refers to what we named "consumption contexts and eating experiences" (clusters 2, 3 and 5) whereas 43.7% refers to what we named "food ingredients and food preparation" (clusters 1 and 4). Concerning the consumption contexts and eating experiences category, three clusters opposed to each other. Cluster 3 (22.6%) and 2 (15.1%), named "affective experience" and "food quality & price" respectively, refer to consumer experience; whereas cluster 5 (18.4%), refers to "consumptions contexts". Concerning the food ingredients and food preparation category, we found two clusters. Cluster 1, named "food processes and preparation", represents a 25.4% of the segmented corpus and cluster 4, named "food ingredients and origin" represents a 18.3% of the segmented corpus. The chi-squared (X 2 ) of the significant vocabulary and variables (Lyon, Paris, students and non-students) that contributed to the creation of each cluster are also presented. The chi-squared represents the relationship between the words used in the creation of the cluster.

Cluster 3, 2 and 5 shows consumer experience when eating out in different consumption contexts.

Clusters 3 and 2 are more oriented to the eating out experience whereas cluster 5 is more associated to the different contexts of consumption. Cluster 3 refers to the notions of affective experience. Two focus groups (G) from Lyon: G4_Student (X 2 = 24.56) and G1 (non-student) (X 2 = 2.18) contributed to the creation of this cluster. Verbs such as "go" (X 2 = 132.89), "eat" (X 2 = 103.3), "envy" (X 2 = 80.43), refers to the fact of "go out" for eating. Moreover, nouns and adjectives such as "boyfriend" (X 2 = 55.88), context (51.84), appreciate (42.22), moment (40.5) also contributed to the creation of this cluster. Cluster 2, contrast with cluster 3 regarding the type of experience perceived by the consumers. Focus groups of students from Paris: G10 (X 2 = 23.21), G12 (X 2 = 5.53), and from Lyon: G5 (X 2 = 12.46) contributed to the creation of this cluster. "Price" (X 2 = 361.03) was a powerful semantic attracter together with "pay" (X 2 = 315.74), "euro" (X 2 = 239.44), and "expensive" (X 2 = PART C. Consumer-related variables 202.88). Those words were also related to the perceived "quality" (X 2 = 98.26), and the "gastronomical" experience (X 2 = 79.12). Three focus groups from Paris, two of non-students: G8 (X 2 = 21.07) and G9 (X 2 = 10.02) and one of students, G12 (X 2 = 4.68), and two focus groups of students from Lyon: G6 (X 2 = 5.89) and G4 (X 2 = 2.44) contributed to the creation of cluster 5. Cluster 5 was characterized by the use of nouns and adjectives associated to different consumption contexts and the ambiance those places evoke. Words such as "food truck" (X 2 = 226.27), "fast food" (X 2 = 138.92), "consumer's tests" (X 2 = 68.99), "bistro" (X 2 = 63.22) refers to contexts whereas "friendly" (X 2 = 59.15), "warmth" (X

Discussion

The objective of this study was to understand how consumers' representations about food in different consumption contexts could influence consumers experience. This could help to assess the possible differences in hedonic responses found in context studies.

PART C. Consumer-related variables Overall, French consumers described a good meal experience as one that involves a convivial environment, the use of natural and tasty food products, and a good quality and price ratio.

Conviviality was pointed out as one of the most important factors for French consumers' when describing food experiences something that has been confirmed by Fischler & Masson (2008).

This study reveals that consumer experience in a given food consumption context integrates environment and product-related variables in a way that is specific to that given context.

Environmental-related variables such as the physical context, environment and decoration, were included as part of the consumer experience when evoking gastronomic and local restaurants together with product-related variables such as presentation and preparation. Conversely, in contexts such as workplace or school cafeterias, those variables (environmental and food-related) were not spontaneously associated to consumer experience, except with regards to conviviality. Consumers showed negative attitudes towards those contexts mainly related to the poor food variety and presentation; and the poor physical characteristics of the context. Those results are in line with previous studies that showed consumers' negative attitudes towards this type of institutions, referring to them as "Institutional stereotyping" (Cardello, Bell, & Kramer, 1996;Edwards, 2013).

When looking at the role of conviviality on context studies, both positive (Muñoz et al., 2018) and negative effects on consumer experience have been observed (Di Monaco, Giacalone, Pepe, Masi, & Cavella, 2014). It should be highlighted that consumers underlined the lack of conviviality that consumer tests convey and argued that those contexts cannot offer a full meal experience. This result could explain why in controlled conditions consumers' hedonic responses tend to be lower compare to more natural consumption contexts.

Beliefs and expectations towards consumption contexts were associated to different types of products and processes. Consumers associated school cafeterias, fast food restaurantsand in the case of Parisian groups, brasseries and bistrosto the use of industrial products including frozen, canned as well as vacuum products. Consumers insisted that due to the volume of the served food and prices, it is difficult to find fresh and natural ingredients in those contexts, especially in the school cafeterias and food chains. Previous studies have associated consumers' negative attitudes and beliefs towards institutional meals, arguing that good food quality cannot be expected when considering the volume of the food produced and the low price of the menu (Cardello, Bell, & Kramer, 1996;Edwards & Hartwell, 2009;Edwards, 2013). Conversely, small and gastronomic restaurants were associated to the use of fresh, seasonal and local ingredients as well as homemade prepared dishes. Consumers believed that due to the price they pay for the food, the quality of the ingredients and preparations have to be accorded. They expected to find those ingredients when they go to a restaurant. From those results two main findings could be highlighted. First, food value (associated to the price payed for food) seems to have an important effect on consumers' meal experience related to consumer satisfaction. Consumers expect to have a meal that corresponds to the fair price they have to pay for it (Timothy et al., 2016).

Second, those results confirm the actual trends that show a higher interest about natural, bio and local PART C. Consumer-related variables ingredients (Agence Bio & Spirit Insight, 2019) not only in terms of consumer goods but in terms of meal experiences. According to the food service study carried out in 2013 by GIRA Conseil (2013),

French consumers look at the quality of the ingredients more than before due to the scandals associated to the food industry and they search to go back to the traditional processes. Considering those two results consumers' expectations towards different consumption contexts may differ not only with regards to the physical context but to the food value and ingredients they expect or think to find in a particular context. Hence, in consumer tests, where no food value may be perceived and consumers showed to have negative attitudes towards the products or ingredients used, it could be assumed that consumers' hedonic responses may differ compared to other contexts.

Taste was also highlighted by the participants as one of the most important factors of the meal experience. However, the role of taste on consumer experience seems to differ depending on the context of consumption. In a workplace or school cafeteria taste was not as important as in a restaurant like brasserie, bistro or gastronomic restaurant. It was the same for the visual aspects of the product and texture. This arises the question about comparing hedonic responses between different consumption contexts where consumers' product evaluation may differ depending on the context.

The lexicometric analysis showed clear differences regarding consumers' region and type of population. The groups from Paris focused their discourse on context-related variables whereas the groups from Lyon focused more on product-related variables. This could be explained by the particularities of the "lyonnaise cuisine" compared to the more general "French cuisine" that can be found in Paris (Fischler & Masson, 2008). Moreover, it should be mentioned that Lyon has a specific gastronomic culture and environment that have been appropriated by the local population, as participants have mentioned during the discussions. Clear differences were also observed in the discourse students and non-students' groups built. Students groups highlighted the importance of conviviality when eating out as well as the price, whereas the non-students underlined the quality of the food and the authenticity of the ingredients. Those differences between what is important when eating out could be explained by generational and consumption habits differences and preferences as previous studies have shown regarding consumer behavior [START_REF] Ferzacca | Sometimes they " ll tell me what they want '': Family and inter-generational food preferences in the food decisions of Singaporean women q[END_REF][START_REF] Urdapilleta | Culinary choices: A sociopsychological perspective based on the concept of Distance to the Object[END_REF].

As for any qualitative test the results of the study cannot be generalized but they reveal some important insights about this regional groups and populations.

Conclusion

This study reveals that consumers' representations about food in different contexts contribute to consumer experience. Beliefs and expectations towards a particular context of consumption are intimately related to the beliefs and expectations towards the food served in that particular context.

Consumers expect to find natural, fresh, local ingredients in small and gastronomic restaurants, whereas they expect or think to find processed food at workplace or school cafeterias and food chains.

PART C. Consumer-related variables Therefore, we could hypothesize consumers' expectations about food may influence their experience in a particular context and in turn, their evaluation. Additionally, this study shows that the relative contribution of contextual variables to consumer experience differ depending on the consumption context. Thus, context studies may pay careful attention on the inferences made about the presence or absence of contextual variables when comparing context studies as these variables may not have the same weight depending on the context and the studied population. Hence, it is important to identify and characterized the studied population and then, understand what are the contextual variables that matter for their consumer experience in each particular context in order to be able to explain context effects on hedonic responses.

Supplementary data

A similarity analysis was also conducted together with the correspondence analysis and top-down hierarchical cluster analysis. This analysis was also performed to iRaMuTeQ -a R interface for multidimensional text analysis and questionnaires -(iRraMuTeQ 0.7 alpha 2, © 2008-2014 Pierre Ratinaud). This analysis was conducted to understand how words were associated within participants'

discourse and the differences between the groups variables: Lyon versus Paris, and students versus non students. This similarity analysis was performed base on co-occurrence (when two or more words are used simultaneously in the same statement).

Figure 1 shows the discourse structure of the groups from Lyon and Figure 2 the discourse structure of the groups from Paris. We observed that in Lyon "manger" that means "eat" and "aller" that means "go" are much closer than in the groups from Paris whereas both groups related "cantine" that means "canteen" to the verb "eat" ("manger") whereas the verb "go" ("aller") was related to "restaurant".

"Restaurant" was associated to the verb "penser" that means "think" by the groups from Lyon, whereas it was associated to the verb "voir" that means "see" by the groups from Paris. Regarding the verb "go" ("aller"), the groups from Lyon associated this verb to "qualité" that means "quality" and "quality" to "produit" that means "product", whereas the groups from Paris associated this verb first to "product" and then to "quality", and this to the notions of fast food and food trucks.

Figure 3 shows the discourse structure of the groups of non-students and Figure 4 the discourse structure of the groups of students. A clear visual difference regarding the structure of the discourse is observed between both groups. The groups of non-students discussed at the same time about "go"

("aller") and "eat" ("manger") whereas in the groups of students there is a clear distance between both verbs. Non-students associated "go" and "eat" to "restaurant" and from there they discussed about the "product" ("produit") and the "quality" ("qualité"). Moreover, restaurant was associated to the word "chose" that means "thing" and this with the word "gout" that means "taste", that was related at the same time to the word "sentir" that means "feel". Conversely the groups of students, mainly discussed by using the verb "go" ("aller") and from there they discussed about going to a "restaurant"; going to "eat" ("manger") and going to the "canteen" ("cantine"). Additionally, the verb "go" was also associated to the verb "think" ("penser"). Moreover, contrary to the non-students' groups they discussed first about the "quality" that lead them to discuss about the "product" ("produit") what was also related to "homemade" ("fait maison").

Those results give an idea about how the different thinking process of the groups was built during the focus groups discussion.

Conclusion

The main objective of this chapter was to examine if consumer experience was influenced by consumers' representations about food in different consumption contexts.

To achieve this objective twelve groups of discussion (n = 86) were conducted in two different regions Paris and Lyon with two different populations: students and non-students. Differences in context-related variables were observed between contexts of consumption and they were associated with consumers' positive and negative attitudes. Conviviality was highlighted as one of the most important variables when eating out independently of the context of consumption.

However, not all consumers experience it in the same way depending on the context, especially as regards gastronomic restaurants where some students described as cold environments. Decoration was highlighted and positively evaluated when consumers discussed about gastronomic restaurants whereas it was not the case for the workplace and school cafeterias, and fast food chains. Regarding consumer tests, consumers showed negative attitudes towards those contexts when discussing about food experience. Consumers agreed that such context cannot be described or considered as a food experience due to the lack of conviviality and served food.

Hypothesis 2: consumer-related variables could be intimately related to the served food in a particular context.

Differences in product-related variables were observed between contexts of consumption and they were associated to consumers' expectations and beliefs towards the served food. An important discussion between homemade and industrial products were set by the consumers who related the former to natural, local, seasonal and tasty ingredients; whereas the latter was associated to the use of chemical ingredients, food industry scandals and unhealthy ingredients. Consumers also associated the use of these two type of products and processes to different contexts of consumption according to the volume and price of the food offer. Local and gastronomic restaurants were associated to homemade preparations whereas workplace cafeterias and fast food chains were associated to industrial processes.

Hypothesis 3: differences between the two regions could be observed in terms of context and product-related variables due to gastronomic cultural differences.

The quantitative analyses allowed to identify differences among the groups from Paris and Lyon. The groups from Paris were more focused on different context experiences related to the decoration and to the price of the menus. Conversely, the groups from Lyon were more focused on product-related variables such as food preparation and the use of ingredients. Both regions agreed about the PART C. Consumer-related variables importance of conviviality within the consumer experience.

Hypothesis 4: differences between the two groups of populations could be observed in terms of consumer experience due to consumption habit differences.

As in the case of the regions' comparison, the quantitative analysis showed differences in the discourse that students and non-students had when describing meal experiences. The students' groups were more focused on the affective experiences and the price that eating-out entails that non-students' groups who focused more on the quality of the food. Moreover, differences in terms of culinary skills were observed between both populations what may explain the difference in terms of consumer experience between the students and non-students' groups.

The present study shows that consumers' representations about food in different consumption contexts involves different contextual variables. In some contexts, consumers' representations about food may entail more product-related variables and price; whereas in others, environmental-variables such as the conviviality of the shared moment between friends may be more considered than the actual served food.

This reveals that when comparing context studies, consumer hedonic evaluation may be affected not only by the presence of contextual variables, but by the way in which those variables are integrated and matter for consumer experience.

This study also highlights the importance of consumers' beliefs and expectations towards the food served in a particular context. It shows that consumers associated different type of products to different type of contexts. Consumers, especially non-students, pay attention to the product characteristics, preparation and origin of the ingredients when eating out, considering those variables as part of the consumer experience. The negative attitudes consumers have shown towards industrial products and processes may not be fully considered when consumers perform a hedonic evaluation in a consumer tests. Therefore, special attention should be place on those variables when context studies comparisons are made.

Chapter 8. The role of the evaluation task on context studies

Introduction

The literature review (chapter 1 and 3) has shown that within the context effects, the evaluation task may play a major role on the way consumers evaluate and judge a product. However, in the studies looking at context effects, this variable has not aroused the same interest as other contextual variables such as environmental-related variables or product-related variables.

Differences in the type of evaluation task have shown to influence consumers' hedonic responses in controlled conditions. The number of questions (Prescott et al., 2011), order of presentation [START_REF] Earthy | Effect of question order on sensory perception[END_REF] and formulation (Popper et al., 2004) have shown to influence consumers' perception so in turn, consumers' hedonic judgement. Those differences in consumers' hedonic judgement could be associated to framing effects where different characteristics of the food product may be highlighted depending on the way the evaluation task is presented [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF]. Then, consumers may point their attention towards those specific characteristics perceiving, and differently judging the food product according to the evaluation task.

Consumers' hedonic responses are usually collected through a global question about the overall liking of a product (synthetic evaluation task), or through a global question followed of a series of product' attributes ratings (analytical evaluation task). Those differences in the formulation of the hedonic evaluation task have shown controversial results regarding differences between hedonic responses (Figure 10). Some authors have found significant effects when analytical tasks are formulated [START_REF] Earthy | Effect of question order on sensory perception[END_REF]Popper et al., 2004;Prescott et al., 2011), whereas others authors have not reported such effect (Gacula et al., 2008;Jaeger et al., 2013).

Those possible effects of the evaluation task on consumers' hedonic responses have interrogated sensory and consumer scientists. However, those questions have not been further investigated when it comes to context studies. Hence, if consumers' hedonic responses may be affected by the evaluation task in controlled conditions, does the evaluation task influence hedonic responses in natural consumption context?

This chapter aims to go a step further in the field of context studies and to bring some insights with regards to consumer hedonic evaluation in natural consumption contexts. As highlighted in the literature review (chapter 1): attention, experimental procedures and measurement tools are some of the evaluation task-related variables that may played a key role on consumer hedonic evaluation. One of the main differences related to the task between consumer tests in controlled conditions and natural consumption contexts is the attention directed to the evaluation task in the former (Köster, 2009;Köster, 2003). Consumers in natural contexts may play indeed less attention to the evaluation task due to the presence of other contextual variables.

Figure 10. Mean ratings of overall flavor liking (and SEM) for a tea sample when comparing synthetic (overall liking only) and two analytical (overall liking plus attributes) evaluation tasks (Retrieved from Prescott et al., 2011).

Hence, when two different formats of the evaluation task (synthetic or analytical) would be presented in natural consumption contexts, larger differences between the hedonic responses of consumers should be found (Hypothesis 1).

Additionally, product-related variables have shown that culinary preparation had also an impact on consumer hedonic evaluation due to the changes on the sensory attributes of the product (De Graaf et al., 2005;[START_REF] Donadini | Influence of preparation method on the hedonic response of preschoolers to raw, boiled or oven-baked vegetables[END_REF]. Besides, as it was showed in the previous chapter, differences in the culinary preparation have been related to consumers' expectations for products or dishes in particular contexts. Thus, consumers may be more sensitive to potential differences originating from culinary practices.

Hence, the effect of explicitly asking consumer to rate sensory attributes in a natural consumption context would be even greater for products that involve culinary preparation than for ready-made products (Hypothesis 2).

To test this hypotheses, a comparison was made between two evaluation task formats (see Appendices 6 and 7): synthetic (overall liking scores) and analytical (overall liking scores plus sensory attributes ratings). Following a similar protocol of the one used by Prescott, Lee, & Kim, (2011), participants evaluated two products categories (pizza and bread) and three versions of a product within the same category (homemade, mixed, and readymade pizza) in a staff and university cafeteria.

Introduction

Differences in hedonic responses to a given food product are often reported when comparing data obtained in different evaluation contexts, such as laboratories, central location tests (CLT) or natural consumption contexts (Galiñanes Plaza, Delarue, & Saulais, 2019). The effects of the physical location, social facilitation or availability of food options are the most commonly suggested factors to explain such differences. Köster has also suggested that the context of consumption could affect consumers' sensitivity to product characteristics (Köster, 2009). Indeed, the differences in perception may be more or less salient depending on the expectations and beliefs consumers may have towards that particular context of consumption. In addition to this, consumers may experience dishes that have undergone different degrees of culinary preparations depending on the context. For example, a regular dish like "Bolognese pasta" may be differently cooked at home, at the cafeteria, or at the Italian restaurant, which will in turn modulate the sensory characteristics of the product. This experience may reinforce context-induced differences in perception arising from expectations and beliefs.

Test procedure and evaluation tasks may also contribute to the observed differences in the outcome of hedonic test from one context to another. Indeed, studies considering hedonic responses in different contexts do not always rely on comparable evaluation tasks and experimental procedures -hedonic scales and questionnaires differ from one study to another and in some cases the procedure followed also differs between contexts within the same study (e.g. at the CLT location the food is evaluated after few bites, whereas at home the food is evaluated after a complete consumption) (García-Segovia, Harrington, & Seo, 2015;Holthuysen, Vrijhof, de Wijk, & Kremer, 2017;Kozlowska et al., 2003;Meiselman, Johnson, Reeve, & Crouch, 2000). This questions the nature and amplitude of context effects themselves.

Framing effects -the fact that the responses to a question are linked to the way it is formulated [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF] -have been reported in several sensory studies. They include differences in hedonic responses depending on: the number of questions (Jaeger et al., 2013;Spinelli, Masi, Dinnella, Zoboli, & Monteleone, 2014), the order in which they are asked [START_REF] Earthy | Effect of question order on sensory perception[END_REF] or the way they are formulated (Popper, Rosenstock, Schraidt, & Kroll, 2004). Differences in the formulation of the task have been related to differences in the accessibility to the attributes of the evaluated product. This accessibility to differences attributes modulate the respondent's perception and leads to different hedonic responses (Köster, 2003(Köster, , 2009)).

Common tasks for hedonic evaluation procedures typically require consumers either to make global judgments (synthetic evaluation task) or to rate successively several sensory attributes in addition to the overall liking score (analytical evaluation task). The choice of one task rather than another may impact the hedonic evaluation itself. For example, Prescott et al., (2011) compared the hedonic responses obtained either with synthetic or analytical evaluation of a product. They found that the mean liking score was significantly higher when using a synthetic evaluation task than when using an analytical evaluation task. The authors argued that asking several questions to consumers such as PART D. Evaluation task-related variables rating sensory attributes may focus consumers' attention on specific product characteristics, modulating their hedonic responses. However, such an effect has not always been observed (Gacula, Mohan, Faller, Pollack, & Moskowitz, 2008).

It is thus worth noting that Prescott et al.'s results were observed in controlled testing conditions, where consumers' attention is focused on the task, regardless of its complexity. It is not known whether such effects would be similar in natural consumption contexts, where the attentional focus on both the task and on products' characteristics may be less important. One can hypothesize that in such conditions, the difference between synthetic and analytical evaluation tasks would be even larger because of the additional cognitive cost of the latter. Moreover, we could assume that in a natural consumption context, consumers would be more sensitive to potential differences originating from culinary practices. Therefore, we could hypothesize that the effect of explicitly asking them to rate those attributes in a natural consumption context would be even greater for products that involve culinary preparation than for ready-made products.

In order to address these hypotheses, the first objective of this study was to assess whether the differences between synthetic and analytical evaluation tasks replicate in a natural consumption context. Following a protocol similar to Prescott, Lee, & Kim (2011) we examined consumers' liking scores for food products using either a synthetic (overall liking) or an analytical evaluation task (overall liking plus attributes intensity scale) in a student cafeteria. Secondly, the study aims to assess the sensitivity of this effect to product type (i.e. culinary prepared or ready-made). The measures are conducted on two products categories (pizza and bread) and three versions of a product within the same category (homemade, mixed, and readymade pizza).

Material and methods

Participants and procedure

The study took place between the 8th of March and the 21st of March 2018 at the staff and student cafeteria of the Ecole Centrale of Lyon, France (a higher education institute not related to food science nor to consumer science). Participants in the study were recruited each day at lunchtime among the consumers who had freely chosen one of the products (pizza and/or bread) that was the focus of the study. At the checkout counter, they were asked whether they wanted to participate in a survey as part of a research study, and if they could fill out a questionnaire on the food that they had freely selected.

A total of 456 questionnaires were collected at the end of the three days of study.

Samples

Two different products were selected to test the sensitivity of participants' responses to variations of food preparation: bread and Margherita pizza. Bread was selected as a control product and it did not suffer any changes as regards composition, weight and sensory characteristics during the study.

Conversely, Margherita pizza was selected because multiple modifications in terms of culinary PART D. Evaluation task-related variables -Pizza: tomato flavor, saltiness, fattiness, cheese flavor, soft texture;

-Bread: saltiness, yeast flavor, soft crumb texture, crispiness of the crust, crunchy dough.

Experimental design

Pizza and bread were available as part of the menu during the three days of study. However, the bread was only evaluated during the first two days. Each day, a comparison was made between the group receiving only the synthetic evaluation task and the group receiving the analytical evaluation task.

Table 2 shows the design of the experiment regarding the products used and their respective culinary modification and the evaluation task. four main dishes (pizza one of them) and several desserts. Once at the checkout counter, we spotted participants who had selected the concerned products on their trays and we asked them whether they wanted to participate in the study, and if they could fill out a questionnaire. Then, they were randomly given either a synthetic or an analytical version of the questionnaire. We told them to fill it while eating and to return it before leaving the cafeteria.

Data analysis

Liking data were analyzed using a two-way ANOVA with interaction, where the type of culinary preparation and the type of task were included as main effects. When the ANOVA showed a significant effect (p < 0.05), post-hoc LSD test was applied. Besides, for each product, the difference between the two types of task was tested separately using independent samples Student's t-test.

( XLSTAT, Addinsoft (2019). statistical and data analysis solution. Paris, France).

Nota bene: we did our best to select different participants each day. However, as the study was conducted in a natural consumption context, we cannot exclude that some participants took part of the study twice (e.g. on Day 1 and Day2). Should this have occurred, it would had been marginal. We thus treated the data from each day as independent groups.

Results

Figure 1 shows mean values for the liking scores for bread. There was no overall difference between the liking scores obtained with the two evaluation tasks (t (180) = -0.435, p = 0.664). Nor did we observe any session effect over the two days of study for both the synthetic (t (87) = 1.039, p = 0.302) and the analytical evaluation task (t (91) = -0.959, p = 0.340).

In the case of the Margherita pizza (Figure 2.A), there was no overall effect of the task format (F (1, 268) = 0.190; p = 0.663). However, liking scores were significantly affected by the differences in the culinary preparation: the readymade version obtained the lowest liking scores (F (1, 267) = 5.256; p = 0.006). The effect of the interaction between the culinary preparation and the task format was also significant (F (1, 267) = 3.690; p = 0.026): liking scores for the homemade version were significantly lower when participants performed the analytical evaluation task (t (86) =2.964, p = 0.004). As a result, although the test was conducted in a pure monadic way, the final product ranking derived from such a test changes depending on the task format (Figure 2.B). Suppose a food service company tested their products with the synthetic task, they would have concluded that homemade was the best liked pizza, followed by the mixed (although not statistically different) and the readymade being the least liked.

Whereas if they had used the analytical task they would have concluded that their regular 'mixed' pizza would be liked significantly more than the other two.

Discussion

In the synthetic evaluation task the homemade version of the pizza was the most liked whereas in the analytical evaluation task the 'mixed' version was liked the most. This result is consistent with previous observations that liking scores are more sensitive to the task format for highly liked products than disliked products [START_REF] Earthy | Effect of question order on sensory perception[END_REF]Popper et al., 2004). This could explain why, in our study, the task format did not affect liking scores for bread, which received much lower liking scores overall than pizzas. Moreover, bread was used as a control product that did not vary throughout the experiment and that, contrary to pizzas, was not subject to culinary preparation. We could thus hypothesize that participants evaluated it as a whole, regardless of the task.

Thus, contrary to what was observed for bread, the task format did change the mean score for the homemade pizza. Pizza being a multicomponent food, it could be prone to analytical evaluation when attributes are provided on the evaluation form. This could be considered as a framing effect where the PART D. Evaluation task-related variables participants' attention may have pointed towards particular characteristics of the product, such as the dough or the tomato sauce, thereby modulating participants' liking scores (Cardello, 2017). Besides, it should be noted that, the mixed pizza was the regular product that is usually served in this canteen.

Thus, participants may have paid less attention to specific attributes when evaluating this version than the other two, which were less familiar. In particular, the homemade pizza may have exceeded expectations overall and was scored higher with the synthetic task, but was scored lower when participants' attention was focused on specific sensory attributes. Conversely, the liking scores of the mixed and the readymade pizzas tended to be higher with the analytical task (although not significant).

This study reveals that differences in task format may affect participants' responses to liking scores in the case of multicomponent products such as pizzas. Should this be confirmed with other product categories, it would be of particular importance for the evaluation of dishes served in eating contexts (such as restaurant, cafeterias, canteens) where different degrees of culinary preparation may be performed and are to be expected. Thus, when conducting consumer tests in natural consumption contexts where food is subject to culinary preparations, asking participants to rate attributes may influence their attention, and therefore their perception of dishes' attributes.

Moreover, this study reveals that not only liking scores differ depending on the task format, but also the final ranking of the products. This may indeed entail different managerial decisions for industrials when it comes to the launching of a product. Here, the synthetic evaluation task would have concluded that the homemade pizza was the best liked and the readymade being the least liked, while the analytical evaluation task (which is more often used in satisfaction surveys in cafeterias) would have concluded that the regular 'mixed' pizza would be liked significantly more than the other two. It would be then interesting to test whether similar results would be obtained in a monadic sequential way although proceeding this way in a natural consumption context would impair the ecological validity of the design. Further studies on the effect of the evaluation task on consumers' hedonic responses in natural consumption contexts would provide better understanding of which aspects of the product matter to consumers when eating out and how those aspects are integrated in their sensory evaluation.

Limitations and methodological aspects

Initially the work presented in this chapter included two more products: a strawberry yogurt and a lemon pie with three different culinary preparations as occurred with the pizza. Those two products were selected together with the food catering company as they were frequently consumed, and in the case of the lemon pie, it was easy to prepare.

Those two more products could have helped us to confirm the impact of the task on consumer hedonic evaluation on natural consumption contexts, and the interaction between the culinary preparation and the analytical evaluation task. Moreover, with this design differences in consumer hedonic evaluation between product categories could have been identified. Nevertheless, two main limitations were observed when performing the study:

1. As consumers freely selected their food, the strawberry yogurt option was not selected as much as it was firstly estimated. Hence, not enough data was collected. It is important to highlight that on natural consumption contexts, giving consumers the freedom to choose the products they want to test may entail lower data collection. Moreover, if the tested products need a culinary preparation, it is important to consider that in a natural consumption context, where a food service is fast as in a student cafeteria, chefs do not have the same vision about what an experiment may entail, and that any variation on the original experimental protocol may have a direct impact on the results. More work should be done in collaboration between chefs and researchers when working in context studies in order to define a common objective.

Conclusion

The main objective of this chapter was to examines if consumers' hedonic responses in natural consumption contexts differed depending on the type of evaluation task. To achieve this objective two different evaluation tasks (synthetic and analytical) were performed by consumers in a staff and student cafeteria during their lunch time. Additionally, different type of product categories (bread and pizza) with different degrees of culinary preparation within the product category were tested (homemade, mixed and readymade).

PART D. Evaluation task-related variables

Hypothesis 1: when two different formats of the evaluation task (synthetic or analytical) would be presented in natural consumption contexts, larger differences between the hedonic responses of consumers should be found.

Significant differences in consumers' hedonic responses were found for the homemade pizza version.

This product was liked the most at the synthetic evaluation task, whereas the mixed pizza version was liked the most in the analytical evaluation task. No differences regarding consumers' hedonic responses depending on the evaluation task format were observed for bread and the readymade pizza.

Hypothesis 2: Hence, the effect of explicitly asking consumer to rate sensory attributes in a natural consumption context would be even greater for products that involve culinary preparation than for ready-made products.

Consumers' analytical hedonic evaluation of the homemade pizza version was affected by the presence of sensory attributes ratings. A significant difference between hedonic responses was found between the synthetic and analytical evaluation task, with lower liking scores on the latter. Conversely, liking scores of the mixed and readymade pizza versions tend to increase with the analytical evaluation task (although no significant).

This study reveals that differences in task format may affect consumer hedonic evaluation of multicomponent products such as pizzas in natural consumption contexts. Consumers may place their attention to those multicomponent ingredients due to the specific sensory attributes questions. The framing effects of the task may influence consumers' perception so in turn, consumer hedonic evaluation. It should be also mentioned that consumers' expectations towards products, especially those subjected to culinary preparations, may have influenced as well consumers' hedonic responses due to the context of consumption. Consumers may have not expected to find a homemade pizza at the school cafeteria. Therefore, further studies with different product categories and degrees of culinary preparation are suggested to confirm those results.

Moreover, this study reveals that the final ranking of the products also differed depending on the evaluation task. This may indeed entail different managerial decisions for industrials when it comes to the product launch. It would be then interesting to test whether similar results would be obtained in a monadic sequential way although this way would impair the ecological validity of the design in a natural consumption context. This aspect will be explored in chapter 9.

Further studies on the effect of the evaluation task on consumers' hedonic responses in natural consumption contexts would provide better understanding of which aspects of the product matter to consumers when eating out and how those aspects are integrated in their hedonic evaluation.

PART E. Product-related variables

Chapter 9. Framing the evaluation context

During the previous chapters it has been shown that product-related variables such as the amount of food, presentation and information may influence consumer evaluation (chapter 5 and 6). Moreover, consumers' expectations and beliefs towards different contexts have been intimately related to consumers' expectations and beliefs towards the served food in those contexts. Those consumerrelated variables (expectations and beliefs) have shown to influence consumer experience and in turn, consumer evaluation (chapter 7). Additionally, chapter 8 has shown that consumer evaluation change depending on the format a task is presented. Hence, the present chapter integrate those previous results

and insights, and aims to understand how framing effects related to the task modulate consumer hedonic evaluation.

To do so, two different studies will be presented:

1. Eating location as a reference point: differences in hedonic evaluation of dishes according to consumption situation (Article 4)

2. Associations between prior expectations towards meal experience and hedonic responses in the restaurant: the role of information (Article 5)

Introduction

During the previous chapters, the effects of context as a whole have been explored by looking at different level of contextual variables. Environmental and product-related variables have shown to influence the way in which consumers perceived a food in a particular context contributing to the creation of reference points that could be modulated through consumer-related variables such as beliefs and expectations. Moreover, evaluation task-related variables have shown to also influence the way in which consumers perceive a product within a context.

Chapter 3 showed that contexts effects have been further investigated in disciplines such as psychology and behavioral economics through the use of Prospect theory. However, to the author knowledge such theoretical framework has not been applied in the study of context effects when comparing context studies in the field of sensory and consumer science.

The present chapter proposes to go a step further by focusing on the interaction between the food and the consumer in a particular context, drawing consumers' attention to specific aspects of the productrelated variables intimately associated to consumers' beliefs and expectations. By the use of productrelated information, consumers' beliefs and expectations are expected to change the reference points created from environmental and product-related variables, helping to explain contexts effects on consumer hedonic evaluation.

The first study (Article 4) presents a between-subject design where participants evaluated two variants of a given product (ham-olives cake) and they were asked to rate their liking and the level of fulfillment of their expectations in two contexts: a restaurant and a standard testing room (see Appendix 8). Additionally, in each context, half of the participants tested the products in non-informed conditions while the other half tested in informed conditions. By using the insights obtained from previous studies, the information tested was related to food quality, especially to food ingredients and processes: homemade and readymade. Moreover, the effect of the monadic sequential test discussed in chapter 8 was assessed.

The following hypotheses were posited.

1. In the restaurant, consumers liking scores would be higher than in the standard testing room.

2. Information about homemade products would obtain higher rates than readymade products regardless of contexts.

3. The impact of information regarding food quality would differ depending on the testing location.

The second study (Article 5) also presents a between-subject design where participants first answered an online survey focused on consumers' expectations and beliefs towards the food they expected to find in a specific restaurant. Second, they came to the restaurant and were asked to rate their liking of a given dish (tartlets), the intensity perception and liking for different sensory attributes, and their satisfaction (see Appendix 9). Additionally, half of the participants tested the dish when consistent information about food-related factors was given (meeting consumers expectations) while the other half tested the dish when more inconsistent information was presented. In this study we also used the insights obtained from the focus groups regarding food-related variables (food preparation and origin of ingredients).

It was hypothesized that:

1. Consumers' expectations and beliefs towards food in a particular context would help to explain consumers' hedonic responses.

"Consistent information" with consumers' expectations and beliefs would increase

participants liking scores compare to "inconsistent information".

3. Food-related factors would influence consumers' overall satisfaction.

PART E. Product-related variables

The main differences between both studies are:

1. In the first study: 2. Eating location as a reference point: differences in hedonic evaluation of dishes according to consumption situation (Article 4)

Introduction

In spite of numerous studies on the influence of context on consumers' evaluation of food products, mechanisms underlying this influence are not well known. This limits the pursuit of ecological validity of consumer tests of products, and in particular the attempts to contextualize controlled environments (Galiñanes Plaza, Delarue, & Saulais, 2019). To date, most published studies on context have focused on physical variables without addressing test participants' attitudes, expectations or mood states (Edwards, Meiselman, Edwards, & Lesher, 2003;King, Weber, Meiselman, & Lv, 2004;Meiselman, Johnson, Reeve, & Crouch, 2000;Stroebele & De Castro, 2004). Nevertheless, consumers' attitudes, prior beliefs and past experiences have been highlighted as variables that may explain differences in liking and behavior from one consumption context to another (Bernard & Liu, 2017;Cardello, Bell, & Kramer, 1996;Edwards & Hartwell, 2009;Tuorila, Palmujoki, Kytö, Törnwall, & Vehkalahti, 2015). This is because people and locations are most often confounded variables, which makes generalization of measures to other contexts difficult (Delarue & Boutrolle, 2010). We may thus consider that depending on the consumption context, consumers' prior beliefs or expectations toward the location and the quality of the served food may predispose to a different state of mind, leading consumers to a different evaluation and behavior.

This echoes the notion of reference point described by Tversky & Kahneman (1991) in their Prospect

Theory. It suggests that judgement and decision-making are reference-dependent. In other words, individuals do not make absolute judgements but base their evaluation on reference points. Following this theory, consumers can have a different reference point for each context, hence modifying their framework of evaluation.

We conducted a preliminary focus group study on beliefs about the food served in different consumption contexts. It revealed that consumers associate different eating places to different levels of quality, price and product types, which was expected. Moreover, they also associate eating places to different preparation modes: universities or company canteens, fast-food restaurants are strongly associated to readymade products, whereas brasseries and gastronomic restaurants are associated to 'homemade' preparation (Galiñanes Plaza, Saulais, & Delarue, 2018). Consumers' representations about the food preparation mode associated to each context may thus influence how food products are perceived and liked.

Therefore, we can hypothesize that consumers evaluate food within a framework of reference that may be determined by the consumption context itself. In this view, the purpose of this study was to examine the influence of context on consumers' attitudes towards food, as related to their expectations.

In order to test this, we emphasized on the quality (readymade or homemade) of the served food with the hypothesis that consumers' expectations would depend on the evaluation context. More specifically, we were interested in the extent to which expectations (considered as reference points)

were met, or in other words, whether consumers were satisfied or dissatisfied by the food they were served.

PART E. Product-related variables Following a between-subject design, we measured consumers' liking for two variants of a given food (ham-olives cake) as well as the level of fulfillment of their expectations in two contexts: an experimental restaurant and a standard testing room (STR). Additionally, in each context, we tested the influence of information about the quality of the food (readymade or homemade).

Following the assumptions of prospect theory regarding reference points (Tversky & Kahneman, 1991), we hypothesized that (i) in the realistic consumption context, consumers liking scores would be higher than in the controlled setting; (ii) information about homemade products would obtain higher rates than readymade products regardless of context; (iii) the impact of information regarding food quality would differ depending on the testing location.

Material and methods

Participants

Two hundred and eighty-three consumers were recruited via the database of the Research Centre of the Institut Paul Bocuse, social networks and local newspapers. Each participant was randomly appointed to either the "Living Lab" study (restaurant) or the standard testing room (STR) and within each context, to the informed or the non-informed condition (each condition was tested on a different day). One hundred and forty-five participants took part in the restaurant study, (57.2% were female and 42.8% male; mean age 44.45±9.92). One hundred thirty-eight participants took part of the standard testing room (STR) study (61.6% were female and 38.4% male; mean age 43.86±9.93).

Inclusion criteria were age (between 30 and 60 years old) and allergies (no known food allergy).

Cooking habits and eating out frequency responses were collected to better characterize the studied population. Table 1 details their characteristics.

Participants were not financially compensated for their participation, but they were all invited to a free dinner at the restaurant, either as part of the experiment (for the restaurant groups) or as a follow up to the experiment (for the STR groups). Only the STR group knew, upon recruitment, that they would formally participate in a taste test in a controlled condition before the dinner.

At the beginning of the test, participants signed a consent form and then were invited to access the restaurant or to the central location test.

Products

Participants had to evaluate a ham-olives cake (Figure 1), which is a familiar appetizer product to French consumers. Two versions of the product were tested: (i) an industrial, commercially available version (referred to as readymade product in the rest of this article). From this readymade product, (ii) a homemade version (referred to as homemade product) was developed by a professional chef for the purpose of this experiment.

PART E. Product-related variables Regarding the homemade version, the recipe was adapted using the following proportions: 150g ham (≈28.8%), 4 eggs (≈1.54%), wheat flour, canola oil, Emmental cheese, 150g green olives (≈28.8%), milk and yeast. Slight differences in sensory properties between these two versions were detected in an internal tasting session (notably, the readymade cake was perceived as drier than the homemade version, and the olive taste was less strongly perceived). Cakes were served in slices (1cm) and care was taken to make them equally thick in all conditions. The same quantity of product was thus served in the restaurant and in the STR contexts in order to avoid influences of food quantity or differences in the eating reference unit (Rozin & Tuorila, 1993). However, we did not measure the quantity of food that participants consumed.

The readymade cakes used throughout the experimental campaign came from a single batch and were stored in a cold chamber at 4.5°C. On each test day, five readymade cakes were removed from the cold chamber and placed at room temperature half an hour before the beginning of the service.

The homemade cakes were prepared using the same pan model as the readymade version to ensure that both variants had very similar appearance. They were made the same day and at the same hour for each testing session in order to limit sensory variations due to ageing and drying out.

Each product sample was assigned a 3-digit code displayed by a sticker on the presentation plate. All samples were presented sequentially at room temperature in a balanced and randomized order between and within sessions.

Settings

To compare participants' responses in natural and in controlled situations, the experiment was conducted in two settings: a restaurant setting (restaurant) and a standard testing room (STR).

Contextual variables such as portion size, presentation, cutlery, information, timing and social interaction were considered in the experimental design.

A. "Living Lab" restaurant

The natural setting was that of the "Living Lab" restaurant of the Institut Paul Bocuse (Figure 2.A.)

This restaurant is a real commercial restaurant, open to the public and known locally as such. It is also a living lab, in which a number of contextual and product variables can be controlled for, in order to conduct research. Each day, the tables were organized according to the reservation list and set up following a schema. Light and temperature were also set and controlled during each service. Once participants signed the consent form they were welcomed to the restaurant and conducted to their table.

PART E. Product-related variables were conducted at two time slots: 7pm and 7.30pm. This organization facilitated the service at the restaurant and the balance presentation of the two cake versions per day. Participants in the first time slot received the homemade version first, whereas in the second time slot participants received the readymade version first. This order was balanced over the week.

The two experimental conditions (non-informed and informed) were conducted on separate days to avoid confusion and uncontrolled information.

Experimental procedure and evaluation task

In all four experimental conditions, participants were presented with samples of the two product versions. The order of presentation of the products was balanced across subjects in each group.

Participants were asked to rate their liking for the appetizer (ham-olive cake) on a 11-point hedonic scale ranging from "dislike extremely" to "like extremely", and to rate the extent to which the product had met their expectations on a bipolar 11-point scale ranging from "lower than my expectations" to "higher than my expectations" with a midpoint corresponding to "meets my expectations". Finally, consumers also rated their preference between the two versions together with an open-ended question about their choice. All responses were collected using a paper form.

Demographic information (gender, age, and other consumers' characteristics) was also collected at the end of each questionnaire.

Data analysis

Liking and fulfillment of expectations data were analyzed using a multi-way analysis of variance with the subject effect nested in each group (information condition, setting, presentation order). All testable factors and interactions were tested and a step-by-step analysis was run to remove the non-significant interactions using Matlab 2017. The best models to explain liking (after 11 rounds) and fulfilment of expectations data (after 9 rounds) were selected and presented in the present paper. When the ANOVA showed a significant effect (p < 0.05), Tukey's test for pairwise comparisons was used (SPSS v.16, SPSS Statistics, Chicago, I).

With regards to fulfilment of expectations data, scores ranging from "lower than my expectations" to "meets my expectations" were converted in negative scores ranging from "-5" to "0" and those from "meets my expectations" to "higher than my expectations" were converted in positive scores ranging from "0" to "5".

In order to explore inter-individual differences in liking for each version, we distinguished between respondents who had reported that the product did not meet their expectations (they were named "deceived" consumers for that specific product (scores < 0)) and those who reported that the product met or exceeded their expectations (scores ≥ 0). They were named "satisfied" consumers, for that specific product.

Effects of information

The presence of information as a main effect did not significantly influence participants' overall liking scores (F (1, 280) = 3.16; p = 0.076). Although we hypothesized that information would affect the liking differently depending on the context, we did not observe such an interaction. Nevertheless, the presence of information affected the liking differently depending on the product version, as revealed by the significant product*information interaction (F (1, 280) = 6.18; p = 0.014). Post hoc Tukey (HSD) pair-wise comparison showed that the homemade version was not affected by the presence of information (p = 0.964) while the use of the label negatively affected the liking scores of the readymade version (p = 0.024) (Figure 4). As a result, the difference in liking scores between the homemade and the readymade cakes was larger (1.8 points on the hedonic scale) when information was given. Tukey (HSD) post hoc shows that participants' scores of fulfillment of expectations were significantly higher for the homemade version compared to the readymade one (p < 0.001). Participants also rated higher their fulfillment of expectations in the restaurant compared to the STR regardless of the product version, information condition and order of sample presentation (p = 0.009).

Effects of information

Participants' scores of fulfillment of expectations were not affected by the information conditions (F (1, 279) = 2.01; p = 0.158). Nevertheless, a significant interaction between product and information conditions was observed (F (1, 279) = 4.02; p = 0.046). Higher scores were obtained for the homemade version than for the readymade version regardless of the information condition.

Homemade version met participants' expectations and even overcame participants' expectations as shown on Figure 6. However, in the case of the readymade version, participants' scores of fulfillment of expectations decreased when information was presented, meaning that participants' expectations were not even achieved (negative scores were obtained), whereas in non-informed conditions the readymade version met participants' expectations (Figure 6). classified into two groups: those who had reported that the product did not meet their expectations they were named "deceived" consumers for that specific product (red) and, those who reported that the product met or exceeded their expectations were named "satisfied" consumers, for that specific product (green).

Discussion

The purpose of this study was to assess the influence of the evaluation context on consumers' expectations regarding the quality (readymade or homemade) of the served food and on its subsequent evaluation. We hypothesized that consumers' prior expectations would depend on the evaluation context and that this would directly impact the liking scores.

Liking

Results indicate that participants liked the products significantly more in a natural consumption context than in a standard testing room (STR), supporting the notion that consumer product evaluation may be context-dependent (Boutrolle et al., 2007;Holthuysen et al., 2017;King et al., 2004;Meiselman et al., 2000). Some contextual variables such as the ambiance and social facilitation at the restaurant may also have influenced those results. The environment at the restaurant was warm and PART E. Product-related variables friendly, whereas the ambiance at the STR was colder and participants did not have the possibility to discuss with each other. Some of the participants in the STR stated that they "felt like they were sitting in an exam" and this might have modulated participants' mood and therefore their liking [START_REF] Giboreau | Sensory and consumer research in culinary approaches to food[END_REF][START_REF] Porcherot | Measurement of selfreported affective feelings when an aperitif is consumed in an ecological setting[END_REF]Sester et al., 2013). Moreover, the way products were consumed in each context could also explain differences in liking scores. In particular, in the restaurant, participants had the possibility to drink ice tea while they ate the cakes. This factor, which we consider as part of the context, could have contributed to the increase of liking scores in the restaurant. Indeed, several studies have shown an increase in the liking scores when specific combinations of food and drinks are consumed together (Di Monaco, Giacalone, Pepe, Masi, & Cavella, 2014;[START_REF] Hersleth | Effect of contextual factors on liking for wine-Use of robust design methodology[END_REF]). Yet, a closer look at the responses from the 32% of participants who preferred to drink water does not show such an effect, although this could not be formally tested in our ANOVA model. Meanwhile, we cannot exclude that drinking ice tea could have modulated participants' perception of the cakes and therefore could have resulted in a product*testing condition interaction.

Another hypothesis is that the evaluation task itself, and not only the product, may have been perceived as different in those two contexts: participants may have integrated other aspects related to the consumption experience (environment, occasion, social facilitation, etc.) to their evaluations, increasing their scores at the restaurant regardless of the product versions. Conversely, at the STR, participants were more discriminant towards the two versions. This could be related to a greater attention placed on the sensory evaluation, and the lack of interaction with a drink (ice tea) (Hetherington, Anderson, Norton, & Newson, 2006;Köster & Mojet, 2015).

As regards product evaluation, results show that the homemade version was rated higher than the readymade one, regardless of the contexts and regardless of the information condition. As revealed during the internal tasting session, the readymade cake was perceived to have a drier texture and a weaker olive taste intensity, which was expected to be less appreciated even if these differences were small. We also observed that independently of the context there was a higher consensus on the evaluation and satisfaction of the homemade cake whereas the readymade product resulted in more variety of opinions. Nowadays, consumers are much more concerned about the food industry and the quality of processed food than they used to be [START_REF] Asioli | Making sense of the "clean label" trends: A review of consumer food choice behavior and discussion of industry implications[END_REF]. During our preliminary focus group study, consumers stated that they were able to differentiate a readymade product from a homemade one, underlining the importance of the quality of the food when eating out. Consumers expect to find certain type of quality (homemade) in a restaurant instead of a product they can have at the supermarket or even at home. However, this is different when it comes to the standard tests where consumers do not know what they are going to taste or tend to think that they will test industrial products, so the reference point of evaluation may differ (Galiñanes Plaza et al., 2018).

Besides, the liking for readymade cake was significantly affected by the presence of information.

Several studies have shown the effect of information on consumers' products evaluation as well as its relation to consumers' attitudes and beliefs [START_REF] Baer | The role of contextual information of luxury on emotional responses to perfumes[END_REF]Bernard & Liu, 2017;Schulte-Mecklenbeck, Sohn, de Bellis, Martin, & Hertwig, 2013;van den Heuvel, van Trijp, Gremmen, Jan Renes, & van Woerkum, 2006). Priming on certain type of information, in our case "industriel", can make attitudes and beliefs about that particular information more salient, modifying the final response of the participants (Reis, Alcaire, Deliza, & Ares, 2017;van den Heuvel et al., 2006). Moreover, a significant effect of the order of sample presentation was also observed for the readymade version, especially when it was tested after the homemade version. [START_REF] Lahne | The great is the enemy of the good: Hedonic contrast in a coursed meal[END_REF] showed a similar effect when comparing the liking scores of a dish after a good and a mediocre appetizer. The fact that the homemade cake was higher rated could originate from a contrast effect between both cake versions that was manifest when the readymade version was tested second. The sample presentation order is known to have an effect on consumer hedonic evaluation (Boutrolle et al., 2007). However, to our knowledge this effect has not been explored in natural consumption contexts where consumers do not usually taste two similar products one after another. Conversely, in real life consumers may compare the product they eat to a personal reference point. This would correspond to a pure monadic testing mode. Here, having compared two similar products in a monadic way could have modulated participants' reference points of comparison from one product to another as well as their expectations.

Fulfillment of expectations scores

Concerning the fulfillment of expectations results, higher expectation scores were fulfilled at the restaurant compared to the STR. Cardello (1995) described how the perceived food quality and the expectations about food quality of a same product may differ depending on the context of consumption, underlining how important consumers' mindset about a particular context is when evaluating a product.

In this study we considered those prior expectations about contexts and food quality as reference points. In the case of this restaurant we may assume that the reference point as regards the physical location was high because of its name associated to the prestige of Paul Bocuse. Consumers who came to the restaurant test at the Institut Paul Bocuse usually expect to find high food quality associated to the use of natural and local ingredients, tasty (and costly) food. However, in the STR the reference point was more ambiguous. Consumers usually associate this type of context to the test of industrial or processed products and not to a meal experience. Our data reflect these differences between the two contexts as regards food quality: at the restaurant participants' expectations were fulfilled for the homemade version whereas this was not always the case for the readymade version. Similar results

were obtained in the STR; however, the level of expectations in general in this context was lower as participants came to the STR with a « lower » overall framework which may relatively impact their evaluation. [START_REF] Cardello | Consumer concerns and expectations about novel food processing technologies: effects on product liking☆[END_REF] explains that when expectations are low -even if the perceived intrinsic quality is high -liking scores will decrease as the perceived liking will assimilate the lower expectation. This may explain the differences between both contexts and even more, the differences PART E. Product-related variables when the readymade version was labelled and presented before or after the homemade version [START_REF] Cardello | Consumer concerns and expectations about novel food processing technologies: effects on product liking☆[END_REF]Piqueras-Fiszman & Spence, 2015). The reference point created may have been modulated for these two factors (product information and order of presentation), modifying the fulfillment of expectations scores.

Inter-individual differences

As regards the analysis of inter-individual differences, we observed that the distribution of liking scores differed depending on the product version and could be related to participants' fulfillment of expectations. Overall, the homemade version met or exceeded participants' expectations no matter where it was tested or how it was labelled; however, the readymade version was more disappointing showing a bimodal distribution of the liking scores and fulfillment of expectations. A possible explanation for this result is that a hedonic contrast between both versions and the product-context (inappropriate situation) may occur (Cardello, Schutz, Snow, & Lesher, 2000;[START_REF] Lahne | You'll spoil your dinner: Attenuating hedonic contrast in meals through cuisine mismatch[END_REF][START_REF] Lahne | The great is the enemy of the good: Hedonic contrast in a coursed meal[END_REF].

Conversely, some limitations should be noted and considered for further studies. This study was conducted in a specific location, the Institut Paul Bocuse, a name associated to one of the major references of gastronomy in France and worldwide. Participants came to the STR knowing that they would take part of a study. The STR was located inside of the Institut Paul Bocuse which may have contributed to create a certain degree of expectations that were not met in both contexts. Moreover, it is important to consider that, in both settings, participants were invited to the diner. We have previously mentioned that high food quality was related to higher prices. Thus, the fact that participants did not pay for their dinner may have led them to a lower engagement in either settings, which is a typical weakness of such hypothetical tests (as opposed to non-hypothetical tests implemented in experimental economics). Those limits may contribute to explain the fact that we did not observe any three-way interaction between the context, the product version and information.

Conclusion

The purpose of this study was to assess the influence of context on consumers' attitudes towards food by emphasizing the quality (readymade or homemade) of the served food. We hypothesized that consumers' prior expectations would depend on the evaluation context and that this would directly impact participants' evaluation.

The homemade version obtained a 'higher' reference score on average. This seems to make it less sensitive to variations of context than the less liked readymade version. Information about the product version played a key role on participants' evaluation that may be related to participants' prior beliefs and/or expectations. More generally, information may contribute to the modulation of participants' reference points.

PART E. Product-related variables

Our results suggest that reference dependent theory may be an interesting way to look at consumers' mind-set when performing a context comparative study. By modulating this reference point or framework of evaluation we might be able to explain certain differences between contexts that may not be related to the physical environment itself but to the attitudes or prior experiences consumers have had with the served food in a similar context. Moreover, an important finding is that the context of the evaluation task had an effect stronger than the actual context of consumption (restaurant and STR). In the case of natural consumption contexts such as restaurants, a monadic sequential presentation of the products may decrease the ecological validity of the results. Our data also showed that product order modulate participants' hedonic evaluation as well as the fulfilment of their expectations. From a practical point of view, this result suggests that the task modulates the reference point from where consumers make their evaluation and set their expectations and should thus be carefully considered. Indeed, even in contextualized tests for the industry, resulting managerial decisions may depend on the evaluation task and test design.

Article 4 Limitations

It is important to consider that in the present study consumers' prior beliefs and expectations were not directly assessed so, they were just assumptions built from previous experiments (chapter 7).

Moreover, no value for money was addressed which may have contributed to the lack of results concerning the hypothesis number 3. Consumers may have not perceived a higher lost when tasting readymade products in the restaurant than when they did it in the standard testing room.

Finally, the use of a monadic presentation of the two food versions may have compromised the ecological validity of the experiment as this rarely occurs in natural consumption contexts.

Article 4 Conclusion

This study assessed the influence of context on consumers' attitudes towards food by emphasizing the quality and processes (readymade or homemade) of the served food. According to the hypotheses enounced:

H1: In the restaurant, consumers liking scores would be higher than in the standard testing room.

Results showed that consumer liking scores in the restaurant were higher than those in the standard testing room. On average consumers liked most both products in the restaurant than in the standard testing room. This may be explained by fact that conviviality had an important effect on consumer experience, especially for French consumers. Besides, during the experiment at the standard testing room, consumers expressed to feel like if they were in an exam, which may have negatively influence consumer hedonic evaluation. Moreover, the presentation of the food also differed from one context to another. In the restaurant appropriate cutlery was used whereas in the standard testing room plastic cutlery was used.

H2: Information about homemade products would obtain higher scores than readymade products regardless of context.

Results showed that homemade products obtained higher scores than readymade products regardless of the contexts and information condition. This confirm prior results where consumers indicated that when eating out in restaurants like Bocuse, homemade products are expected to be used in kitchen.

H3: The impact of information regarding food quality would differ depending on the location.

No differences among information condition depending on the testing location were reported. It was expected to find lower liking scores of the readymade product in the restaurant, whereas higher liking scores of the homemade product in the standard testing room by following the loss-aversion principle of the Prospect theory. Unfortunately, that results were not observed. This could be related to the lack of value for money perceived by the consumers in both contexts.

PART E. Product-related variables

The present study showed that product-related information played a key role on consumer hedonic evaluation regardless of contexts effects. This effect could be associated to the modulation of consumers' reference points by consumers' beliefs and/or expectations towards specific product characteristics within a context. The results suggested that framing on those consumer-related factors might help to explain certain differences between context studies that may go beyond the physical environment.

Moreover, a significant effect of the order of sample presentation was observed in both non-informed and informed conditions. This result should be highlighted as in natural consumption contexts consumers do not usually taste two versions of a product as they do in consumer tests. This direct comparison between products may inference wrong managerial decisions when it comes to the product launch as the characteristics of the first tested product may serve as reference for the second evaluated one.

Introduction

What do you expect to find in your plate when you eat out? Considering the variety of eating out contexts, most consumers would probably answer this question with "it depends on the type of restaurant". Consumers' expectations towards food differ depending on the context and situation, and on the meal experience perceived in that particular context (Köster, 2003). Meal experience involves several factors such as food and beverages, environment and, social and management factors (Muñoz et al., 2018;Ozdemir & Caliskan, 2014). Within those meal experience factors, those related to food such as taste, food presentation, or quality have shown to influence the meal experience the most, especially consumer satisfaction (Timothy, Yang, & Kim, 2016). Consumers' expectations if they go to a fancy restaurant are therefore likely to differ from those if they go to a fast food chain.

French consumers are becoming more and more conscious about food authenticity, tradition and terroir when it comes to eating out experiences (GIRA Conseil, 2013). Most consumers search for "local ingredients" that associate to characteristics such as "fresh", "seasonal" and "homemade" food (Agence Bio & Spirit Insight, 2019). Another increasingly important factor is transparency regarding the origin of food, production processes, and ingredients due to the scandals food industry has suffered in the last years. In the restaurant sector, doubts about the use of processed food have increased consumers' concerns and distrust about the quality of the served food and their value [START_REF] Filimonau | Restaurant menu design and more responsible consumer food choice : An exploratory study of managerial perceptions[END_REF]GIRA Conseil, 2013). Additionally, the use of "local", "fresh" and "homemade" food have been positively associated to a better taste compare to processed food (Bernard & Liu, 2017;[START_REF] Costa | To cook or not to PART E. Product-related variables cook: A means-end study of motives for choice of meal solutions[END_REF][START_REF] Spiller | It tastes better because . . . consumer understandings of UK farmers ' market food q[END_REF]. This could be related to consumers' beliefs and expectations that have been shown to influence consumers' hedonic perception, and in turn consumers' hedonic responses [START_REF] Fernqvist | Credence and the effect on consumer liking of food -A review[END_REF]Piqueras-Fiszman & Spence, 2015).

In response to these trends, an increasing number of restaurants in France have started to explicitly signal their dishes as "homemade" on menu cards (GIRA Conseil, 2013). The effect of information about food-related characteristics such as food origin or processes on consumer's beliefs and expectations has been widely investigated (Bernard & Liu, 2017;[START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF]van den Heuvel, van Trijp, Gremmen, Jan Renes, & van Woerkum, 2006). Authors have attributed the effect of foodrelated information on the fact that such information makes certain characteristics of the product more salient to consumers. Therefore, consumers' perception about the product is modulated and in turn, consumers' hedonic responses.

The purpose of this study was to examine the influence of the type of information provided on food preparation and origin of ingredients on consumers' hedonic responses to a product in a natural consumption context. Based on previous works on information disclosure in the restaurant [START_REF] Filimonau | Restaurant menu design and more responsible consumer food choice : An exploratory study of managerial perceptions[END_REF][START_REF] Shawn | Enhancing ethnic food acceptance and reducing perceived risk : The effects of personality traits , cultural familiarity , and menu framing[END_REF], and on consumers' trust on food information (Agence Bio & Spirit Insight, 2019;[START_REF] Kumpulainen | How young people in Finland respond to information about the origin of food products : The role of value orientations and product type[END_REF] information consistent with consumers' beliefs and expectations (previously measured) will prompt more positive hedonic PART E. Product-related variables responses than information evoking more uncertainty. The "consistent information" condition would reinforce participants' beliefs and expectations towards dishes, increasing the liking scores of the products; whereas the "inconsistent information" condition would highlight certain characteristics of the product such as the dish preparation and origin of the ingredients that would contrast with participants' expectations decreasing the liking scores (Piqueras-Fiszman & Spence, 2015).

To address this objective, an experiment was conducted in a restaurant setting with 114 consumers.

Prior to the restaurant visit, consumers' expectations and beliefs towards the food served in that restaurant were assessed through an online survey. Responses from the survey were used to control consumers' expectations and beliefs and validate the information conditions. The experiment examined the effect of menu information regarding food preparation and origin of ingredients on consumers' hedonic responses to the food served in the restaurant as well as on sensory attributes perception. The information was either consistent, in line with consumers' expectations (N=56) or inconsistent, in contradiction with consumers' expectations (N=58). Consumers' food satisfaction, and overall experience satisfaction, were also measured.

Material and methods

Participants

One hundred and fourteen consumers were recruited via the database of the Research Centre of the Institut Paul Bocuse, social networks, and local newspapers. Participants had to be aged between 18 and 35 years. Criteria of exclusion were pregnancy, breast-feeding, food allergies or intolerances, specific diets and/or total aversion to legumes. Table 1 provides more details on their characteristics.

Participants were informed during the recruitment that the lunch was part of a study carried out at the Research Center restaurant. Participants were not financially compensated for their participation and they paid for their lunch at the "Living Lab" restaurant. The price of the menu (type catering classic mid-range) was 15 € (or 7.5 € if participants came with another person) and included an appetizer, starter, a main dish and a dessert.

Before coming to the restaurant, participants were asked to complete an online survey in order to validate the registration process.

Products

One product familiar to the French consumers was selected for the experiment: tomato and goat cheese tartlet (Figure 1). This product is easily found as appetizer in the French culture. To prepare the dough for 30 tartlets, 410 g of wheat flour T55, 310 g of butter, 82 g of whole milk, 82 g of whole egg, 5 g of caster sugar and 11 gr of fine salt were used. The flour and the butter were mixed in a planetary mixer equipped with a flat beater for 2 minutes at low speed. Then, the whole eggs, the sugar, the salt and the milk were added. All ingredients were mixed at low speed until the dough was homogeneous For the filling, the following ingredients were used (for 30 tartlets): 240 g of half-dried cherry tomatoes ("Délice Monde"), 240 g of goat cheese ("Matin d'Avril"), 435 g of whole milk ("lactel"), 110 g of whole egg ("transgourmet France"), 55 g of egg yolk ("transgourmet France"). Half-dried tomatoes were cut in dices of 2 g and the goat cheese in dices of 1.6 g. In order to make the quiche PART E. Product-related variables batter, the milk, the whole egg and the egg yolk were whisked together in a bowl. Then four pieces of half-dried tomatoes (8 g in total/tartlet) and five pieces of goat cheese (8 g in total/tartlet) were homogeneously place in the tartlet as described the schema below (Figure 2). 20 gr of quiche batter were poured over the tartlet bottom. The tartlets were then placed on a pastry tray with a silpat mat and baked for 13 minutes at 180°C in a preheated oven with medium ventilation on and open exhaust until get a uniform golden-brown coloration. The tartlets were kept at room temperature on a wire rack for 20 minutes, then placed and filmed in a cold storage 4°C for at least 1 hour. Finally, the tartlets were taken out from the cold storage 4°C and kept at room temperature for 30 minutes before the service. The tartlet dough was prepared, cooked and freeze 10 days before the experiment due to logistical constraints. As regards the filling of the tartlet, each day of experiment the filling was prepared and the tartlet were cooked following the same protocol. The product was served at room temperature in individual dishes. The choice of this product was made based on previous results from focus groups studies where consumers discussed about the difference between homemade and industrial products as regards the dough of tartlets and cakes as well as the use of local products. Moreover, in order to avoid interactions with other dishes, the tartlets options seemed the most appropriate as it was served at the beginning of the meal as an appetizer.

Settings

The experiment was conducted at the Living Lab restaurant of the Institut Paul Bocuse in Ecully, France (Figure 3). This restaurant is a real commercial restaurant called "Expérience", open to the public and known locally as such (Douglas, Saulais & Giboreau, 2019). It is also a living laboratory, where research in consumer eating behavior is conducted. Each day, the restaurant was set up following the reservation list and a schema. Light and temperature were set and controlled during each service. Once participants signed the consent form they were welcomed to the restaurant and conducted to their table. In regards of their opinions and beliefs towards homemade products, consumers agreed that homemade products included local and seasonal ingredients (32.5% totally agree and 41% agree);

disagreed that homemade products included industrial ingredients (24.8% totally disagree and 35.9% disagree); disagreed that homemade products included frozen ingredients (32.5% totally disagree and 33.3% disagree); and agreed that the homemade products tasted better than the readymade dishes (68.4% totally agree).

Living Lab restaurant

Overall liking scores of the tartlets

The Student t-test revealed significant differences in liking across information conditions (t = 2.127; p = 0.036). Consumers who had the "consistent information" gave significantly higher liking scores (x ̅ =6.7±1.3) than those who had the "inconsistent information" (x ̅ =6.1±1.8) as it is showed in Figure 4. Significant differences on the intensity scores of the sensory attribute buttery flavor of the dough were found between information conditions (t = 2.888; p = 0.005). However, no differences on the intensity PART E. Product-related variables scores were observed for the rest of the sensory attributes when different information was presented:

tomato flavor (t = 0.311; p = 0.756); cheese flavor (t = 0.086; p = 0.932); salty flavor (t = 0.487; p = 0.627) and crusty dough (t = 0.920; p = 0.360) (Figure 5).

Liking Scores of the sensory attributes

The Student t-test showed significant differences in the liking scores of the attribute "crusty dough" (t = 2.697; p = 0.008) across conditions, whereas the liking scores of the rest of the sensory attributes did not vary with the information condition: tomato flavor (t = -0.337; p = 0.737); cheese flavor (t = 569; p = 0.571); buttery flavor of the dough (t = 1.876; p = 0.063) and salty flavor (t = 0.113; p = 0.910) (Figure 6).

Participants' satisfaction

Questions related to food and overall experience satisfaction were compared between both information conditions. The analysis of variance showed significant differences in food satisfaction (t = 2.642; p = 0.009). When consistent information was given participants rated food satisfaction higher (x ̅ =3.6±1.0) than when inconsistent information was presented (x ̅ =3.1±1.0). Additionally, significant differences in overall meal satisfaction were also observed (t = 2.413; p = 0.018); higher scores were obtained when consistent information was given (x ̅ =3.9±0.8) than when inconsistent information was presented (x ̅ =3.4±1.1).

Discussion

This study assessed the effect of information on consumers' hedonic responses when evaluating a product in a particular context. In order to validate the two information conditions, the online survey revealed that participants' expectations towards a specific restaurant were associated to a certain degree of food quality. Participants expected to find a gastronomic cuisine where homemade dishes would be elaborated together with local ingredients, and would be deceived if frozen ingredients would be used, or if the taste of the dishes would not be good. These results confirmed the trends highlighted in the study of GIRA Conseil, (2013) that underlines the importance of food quality for consumers when eating out, and associates it to the use of local ingredients and homemade preparationsrelated at the same time to a better taste -. Participants agreed about the characteristics of homemade products related them to the use of local and seasonal ingredients, and a better taste.

PART E. Product-related variables These results are in line with previous studies who attributed consumers' beliefs towards the use of local ingredients to the positive perception of products (Bernard & Liu, 2017;[START_REF] Spiller | It tastes better because . . . consumer understandings of UK farmers ' market food q[END_REF].

Conversely, participants did not associate homemade products to the use of industrial or frozen ingredients. Since 2013, the label "fait maison" (homemade) has been subjected to an important debate due to the discontent of some restaurateurs who argued about the unfair competition existing between restaurants where the use of readymade products allows to offer lower price menus (GIRA Conseil, 2013). This discontent is also translated to consumers who search the food value and trust when eating out; factors that are associated to the quality of ingredients (Timothy, Yang, & Kim, 2016). The online survey results suggest that consumers' expectations and beliefs towards a particular context are associated to a type of cuisine and food quality. From these results we could validate the information conditions tested in the "Living Lab" restaurant.

When looking at the effect of the type information on participants' hedonic responses, two main effects were observed: an assimilation effect was observed when "consistent information" was given, and a contrast effect was observed when "inconsistent information" was given. As it was hypothesized the "consistent information" condition may have reinforced participants' expectations and beliefs towards homemade product characteristics, increasing the liking scores of the tartlets; whereas the "inconsistent information" condition may have highlighted certain characteristics of the product such as the origin of the ingredients and dish preparation that contrasted with participants' expectations decreasing the liking scores of the tartlets. The online survey studies may confirm those results as participants declared to expect homemade and local ingredients, instead of readymade products.

Although, a 30.51% of the participants in the "inconsistent information" condition declared to be deceived if the taste of the product was not good, 62.71% declared to totally agreed and 28.84% agreed that homemade products taste better than the readymade products. Thus, we can hypothesize that participants' uncertainty with regards to the given "inconsistent information" (provided by our supplier and ingredients from the EU) may have had an impact on their expectations and beliefs towards the product, modulating participants' liking scores. Moreover, [START_REF] Kumpulainen | How young people in Finland respond to information about the origin of food products : The role of value orientations and product type[END_REF] argue that the use of unknown or global origins information negatively impact consumers' trust, influencing product experience. Thus, participants may have associated the "inconsistent information" to the use of readymade products with global ingredients origin, decreasing their evaluation.

Moreover, the type of information about food preparation and origin of the ingredients had a differentiated effect on the evaluation of sensory attributes and their respective liking. Participants perceived and evaluated differently those attributes related to the tartlet's dough. Even if the dough was the same in both information conditions, the presence of information about the process may have framed participants' beliefs towards those specific sensory attributes (buttery and crusty dough)

modulating their perception and in turn, their evaluation (Bernard & Liu, 2017;van den Heuvel et al., PART E. Product-related variables 2006). In fact, the tartlets' dough involves a certain preparation that may be related to the search for homemade dishes participants declared to expect. We could hypothesize that the presence of "inconsistent information" may also have an influence on the perception and posterior evaluation of certain sensory attributes.

Finally, this study reveals that providing different types of information about food-related factors such as food preparation and origin led to differences in food satisfaction and overall meal experience satisfaction. Those results are in line with previous studies that reported that food is one of the most influential criteria for restaurant selection and a determinant of consumer satisfaction (Ozdemir & Caliskan, 2014;Timothy et al., 2016). In this study, participants who received "consistent information" declared to be more satisfied with the food and rated their overall experience higher than those who were presented with "inconsistent information". A possible explanation is that participants payed for their food, and therefore assessed the value for money differently between the information conditions, affecting consumer satisfaction.

Conclusion

The present study showed that providing different information consistent or inconsistent with consumer's expectations and beliefs influence consumers' hedonic responses in a natural consumption context. The online survey showed that participants associated a specific restaurant to the use of homemade products and local ingredients; and these to a better taste. The actual meal experience seemed to be also influenced by the type of information given about product preparation and origin of ingredients. Consumers' beliefs and expectations towards the type of served food could help to explain those results. Further studies should be performed in different contexts in order to explore differences in consumers' beliefs and expectations on food-related factors and their influence on consumers' hedonic responses.

Article 5 Conclusion

The purpose of this study was to examine the extent to which different factors related to food (preparation and origin) influence consumers' hedonic responses and meal satisfaction in a natural consumption context. Moreover, the role of consumers' beliefs and expectations were also assessed.

The hypotheses posited were:

H1: Consumers' expectations and beliefs towards food in a particular context would help to explain consumers' hedonic responses.

Online survey results on consumers' expectations and beliefs towards the food served in the restaurant helped to explain consumers' hedonic responses when different type of information was given.

H2: "Consistent information" would increase participants liking scores compare to "inconsistent information".

The "consistent information" condition reinforced participants' beliefs and expectations towards homemade dishes, increasing the liking scores of the tartlets; whereas the "inconsistent information" condition may have highlighted certain characteristics of the product such as the origin of the ingredients and dish preparation that would contrast with participants' beliefs and expectations decreasing the liking scores of the tartlets.

H3: Food-related factors would influence consumers' overall satisfaction.

Information about food preparation and origin of ingredients influenced consumer satisfaction of food and meal experience. A possible explanation is that participants payed for their food, and therefore assessed the value for money differently between the information conditions, affecting consumer satisfaction.

The present study highlights that context arise expectations and beliefs towards the served food that may help to explain differences in consumers' hedonic responses. Further studies should be performed in different contexts in order to explore differences in consumers' beliefs and expectations on foodrelated factors and their influence on consumers' hedonic responses.

Conclusions PART E

The purpose of this chapter was to understand how framing effects related to the task modulate consumer hedonic evaluation. In the first study, it was observed that information about product-related variables had an effect on consumer hedonic evaluation but that this effect was product-dependent.

Readymade products conveyed a lower consensus among consumers in terms of liking that seemed to be slightly modified when information was presented. Nevertheless, the most significant result obtained from this study from a methodological point of view, was the effect of the order of sample presentation in the evaluation of the products both in informed and non-informed conditions. Even if in natural consumption contexts consumers do not taste two versions of a same product in a monadic sequence, the present results showed an important effect of a first product on the hedonic evaluation of a second product. Effects that increased when food information was presented. This experimental design may have influenced the ecological validity of the results. However, important learnings should be drawn in terms of the methodological approach. In consumer tests, several products are evaluated in a monadic sequential way, what may influence the reference point from which consumers evaluate the second product. Instead, in natural consumption contexts, consumers evaluate products from their own personal reference point that may be associated to environmental, product and consumer-related variables. The interaction between the product and the order of sample presentation showed to have a higher effect on consumer hedonic evaluation that the actual context effect.

Regarding the second study, methodological insights were also drawn from the obtained results. In this study, beliefs and expectations towards food were assessed before the actual hedonic evaluation of a product in a natural consumption context. Those consumer-related variables helped to interpret consumers' hedonic responses when different information (consistent or not with consumers' expectations and beliefs) about food-related variables was presented. Considering the Prospect theory principle 1 and 2, consumers may have created a reference point within the context of consumption that was modulated by information directly associated to consumers' beliefs and prior expectations.

Moreover, as food value was assessed, consumers may have perceived the outcomes of their evaluations as gains and losses depending on the information condition in which they were divided.

Those results suggest that consumers' beliefs and expectations towards a particular context may be related to food-related variables, facilitating the interpretation of different hedonic responses when looking at context studies.

Introduction

Since Meiselman in 1992 argued that eating behavior cannot be studied without the consideration of "real food" in "real" contexts, works have been carried out in an effort to improve the ecological validity of consumer data used in sensory and consumer science (Andersen et al., 2018;Edwards et al., 2003;Hersleth et al., 2015;Sester et al., 2013). However, how and to which degree context influences consumer hedonic evaluation is still unclear. We pointed out that the lack of a theoretical framework behind context studies makes it difficult to understand the role played by contextual variables in consumer hedonic evaluation.

Within this context, this thesis aimed to contribute to understand the conditions under which context affects consumer hedonic evaluation of food products. Through a multidisciplinary approach grounded in Prospect Theory [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF], we proposed a theoretical framework to explain the empirical observations about contexts effects on consumer hedonic evaluation, and to further formalize the effects of context to ensure a better reliability of consumer tests.

Six experimental studies have been presented in this thesis. Each study has been performed in order to explore each of the four categories in which we classified the contextual variables: environment, consumer, evaluation task and product. The first part of the discussion will summarize the responses obtained to the different research questions that we enounced from the two different approaches proposed. We will also discuss about some of the unresolved and new questions that were aroused from the experimental studies to set some perspectives.

Learnings from the experimental studies 1. Classical approach: contextual variables

Advantages and Limitations of studying hedonic responses in natural consumption contexts

Most of the context studies conducted in the last years have focused on the use of new contextual methodologies such as evoked, immersive or virtual reality. However, little research has been conducted in natural consumption contexts except for Home Use Test (Boutrolle et al., 2005;Boutrolle, Delarue, Arranz, Rogeaux, & Köster, 2007;[START_REF] Mörlein | Effects of context and repeated exposure on food liking : The case of boar taint[END_REF]Soerensen, Waehrens, & General discussion Byrne, 2015;[START_REF] Stolzenbach | Understanding Liking in Relation to Sensory Characteristics, Consumer Concept Associations, Arousal Potential and "Appropriateness for Use" Using Apple Juice as an Application[END_REF]. A possible explanation to that is the loss of control over the contextual variables that a natural consumption context entails questioning the reproducibility and transferability of the results. Nevertheless, context and consumer experience of food products cannot be disentangled. Likewise, the context cannot be disentangled from expectations and beliefs towards the product experience.

Chapters 5 and 6 of this thesis represented a necessary preliminary phase of this research. These two chapters included two studies that examined the effect of different contexts on consumer hedonic evaluation and choice. Moreover, consumer and product-related variables were also investigated through the use of information.

The first study (chapter 5) compared consumer hedonic evaluation of a Lebanese Tabbouleh in three different contexts at the Institute Paul Bocuse: Central Location Test (CLT), evoked context and restaurant. In this study, food-related variables such as the amount of served food and the presentation were standardized among contexts. No differences among the three contexts were observed in terms of hedonic evaluation. Neither the effect of information influence consumer hedonic evaluation despite the increasing consensus observed on consumers' hedonic responses in the restaurant when information was given. The second study (chapter 6) explored whether consumers considered information about food-related variables when choosing food, and if this information influenced their hedonic evaluation. A three-day experiment was conducted during a food conference event in the United Kingdom. In the case of the hedonic evaluation, significant differences were obtained for two salad dishes only.

Although the number of consumers per study and conditions was not enough to firmly conclude, methodological insights were underlined from both studies. Regarding the first study and the standardization of the food-related variables (chapter 5), the literature has shown that portion size [START_REF] Brunstrom | Measuring affective ( liking ) and non-affective ( expected satiety ) determinants of portion size and food reward[END_REF][START_REF] Havermans | Food liking , food wanting , and sensory-specific satiety[END_REF]Rozin & Tuorila, 1993;[START_REF] Spence | Are foodrelated perceptions associated with meal portion size decisions ? A cross-sectional study[END_REF] and food presentation (García-Segovia, Harrington, & Seo, 2015;Michel et al., 2014;Piqueras-fiszman et al., 2012;[START_REF] Rowley | Does the visual composition of a dish in fl uence the perception of portion size and hedonic preference ?[END_REF] had an impact on consumer hedonic evaluation. Most studies carried out in controlled conditions do not usually offer a full portion size of a food product and do not present it in the same way it will be consumed in a natural consumption context. This could be associated to the cost that represents to offer full portion sizes to a big number of consumer in controlled conditions. However, presenting smaller portion size may bias the response of consumers depending on the tested product. With regards to the portion size, it is also important to make a difference between the evaluation of a dish and a standardize product such as a cookie, beer, juice, etc. Studies that compared dishes (e.g. cannelloni, salad, lasagna, etc.) in different contexts found that the liking scores of those dishes were lower in CLT (where the amount of served food was lower) than in more natural contexts. In some cases, they did not even consider the General discussion results obtained in the CLT due to the small portion size used (King et al., 2007(King et al., , 2004)). It could be then hypothesized that the way to evaluate a dish may not be the same to evaluate a standardized product in terms of portion size. A snack can be eaten in a small number of bites whereas a dish requires longer time of degustation (Rozin & Tuorila, 1993). This difference in terms of degustation may represent a drawback in terms of logistics when running a test in controlled conditions due to time constraints. Nevertheless, this aspect should be further investigated in order to get more insights about the way dishes should be tested in controlled conditions.

With regards to food presentation, our first study (chapter 5) used the same dish presentation in the three contexts. This could have contributed to the obtained results where no differences in consumer hedonic evaluation were observed. However, it is important to highlight that this was possibly due to the characteristics of the natural consumption restaurant. In the restaurant, food was indeed presented in paper or plastic cups together with plastic cutlery, that is to say a material that is currently used in consumer tests in controlled conditions. Thus, consumers may have been provided inadvertently with a frame of reference that helped them to project themselves in a natural consumption situation as they did in the restaurant. Besides, other studies had shown that the use of incongruent elements to test food in controlled conditions could lower the hedonic response (Petit & Sieffermann, 2007). García-Segovia et al., (2015) showed that when comparing different table settings (plastic tray, home style, gourmet), consumers did not like the gourmet presentation in the CLT whereas they did in the naturalistic settings, and opposite results were obtained when plastic tray presentation was used. This means that even if presentation has an important role on consumer hedonic evaluation, special attention should be put in the way this food-related variable is used in context studies comparison.

As regards the effect of information, our results contradict our expectations as well as results from the literature. We indeed observed (chapter 5) that hedonic scores in blind condition were slightly higher in the CLT and evoked context than in the restaurant. One of the possible explanations to this result was the fact that consumers showed special interest for the experiment; some of them even discussed about the type of questions formulated and the fact that they wanted to give more feedback about the dish when being at the CLT and evoked context. It is important to underline that the consumers in this study were students from culinary arts which may explain their interest about the tested dish.

Conversely, at the restaurant consumers showed to be less involved and interested about the questionnaire. This could be related to time constrains also observed in the study carried out in the United Kingdom where consumers did not want to participate in the study due to the lower time they have for lunch. This raises questions about consumers' mindset when performing a hedonic evaluation depending on the context.

General discussion

As regards the information conditions, no differences in hedonic responses were observed in the two preliminary studies (chapter 5 and 6). This could be related to the lack of given information or wording used (gourmet caterer) as well as the low number of participants per condition and study. In the case of the first study (chapter 5), only CLT and restaurant contexts were compared but both were inscribed in the frame of the Institute Paul Bocuse. Thus, consumers may not have expected to find differences in terms of food quality regardless of the context and condition. Even if no differences in hedonic responses were observed, the consensus among consumers' responses in the restaurant increased. This rose the question that the presence and type of given information could frame consumer evaluation towards a particular characteristic of the product. At the same time, the presence of food information could be related to consumers' beliefs and expectations, modulating the interaction between the product and consumer, and "reducing" the interaction with other contextual variables such as environmental ones. Actually, during the experiment in controlled conditions (chapter 5), consumers discussed about the wording used (gourmet caterer) and the situational appropriateness of a dish like that. They associated the tested dish (tabbouleh) with different contexts according to the given information, so this may explain the low of consensus among participants.

Conversely, at the restaurant, consumers may have actually experience that "situational appropriateness" associated to the dish, relating their hedonic evaluation in a given context to the given information; what may help to increase the consensus among consumers' responses. This underlines two different questions: (1) certain products may be able to pass across contexts (standardized products), whereas others may not, as it could be the case of food dishes or product that require a certain level of preparation (Hathaway & Simons, 2017); ( 2) depending on the context and the characteristics of the product (food quality information), consumer hedonic evaluation may differ according to the situational appropriateness perceived. Edwards et al., (2003) showed that a similar dish (Chicken à la King and Rice) prepared from the same ingredients and a standard recipe, was differently evaluated depending on the consumption context. That is, a readymade tabbouleh can be appreciated at home or at a student cafeteria; while in a restaurant it may not. Two important elements are highlighted by these results, one related to the appropriateness of the dish perceived by the consumers in a particular context, and the other related to consumers' expectations towards that particular dish in a specific context. Those two aspects will be further discussed in the following section (2.1.2.) when consumers' mental representations about food will be addressed.

Additionally, in regards of the nature of information that is given, we observed that consumers in the second study (chapter 6) did not pay attention to the information presented at the menu cards. Instead, they observed the food stand and asked the catering service about it even if the menu cards were displayed on top of the food stand and tables. As [START_REF] Grunert | Sustainability in the food sector: a consumer behaviour perspective[END_REF] describes, the need for food information does not always lead to its perception. Consumers tend to select the information they are interested in and ignore the rest. In this type of events where attendees do not have a lot of time for

The influence of mental representations on consumer experience and hedonic evaluation

Studies comparing natural contexts argue that differences in consumer hedonic evaluation could be explained in part by beliefs and expectations that consumers may bring to a particular context (Cardello, 1995;Cardello et al., 2000;Edwards et al., 2003). Consumer-related variables such as consumer' beliefs and expectations play indeed a major role in the way consumers perceive and experience a product [START_REF] Delwiche | You eat with your eyes first[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Schifferstein | Consumer expectations for vegetables with typical and atypical colors : The case of carrots[END_REF]. [START_REF] Boutrolle | Mesure de l'appréciation des aliments par les consommateurs : état des pratiques et propositions méthodologiques[END_REF] affirms that each of us has a personal experience with a product that allows us to determine what a product is, how it tastes and where we would have it just by seeing it. This is due to the mental representations consumers form after several exposures to a product in a particular context [START_REF] Sester | modulation de l'expérience d'une boisson par le contexte : apport de l'immersion à l'étude des influences contextuelles sur le comportement alimentaire[END_REF]. Then, once consumers have set mental representations (knowledge and beliefs) about a product or context, these will create expectations that will modulate consumer experience, and in turn, consumer hedonic evaluation (Piqueras-Fiszman & Spence, 2015).

Although context studies refer to expectations to explain differences in consumer hedonic evaluation, those studies do not evaluate prior expectations towards contexts in order to determine the possible relation with their hedonic data. As mental representations can create expectations, the second objective of the thesis was to examine if consumer mental representations about food in different contexts could influence consumer experience (chapter 7). A qualitative study was carried out with a total of 86 consumers from two different regions (Paris and Lyon) and two different types of population (students and non-students). The results showed that consumer mental representations towards food were intimately associated to the context of consumption and different contextual variables. Important differences between homemade and industrial products were discussed by consumers and associated to different consumption contexts. Different affective experiences were also associated to different contexts and conviviality was, with taste, among the most important criteria for consumers when eating out. This reveals that when comparing context studies, consumer hedonic evaluation may be affected not only by the presence of contextual variables, but also by the way in which those variables are integrated and matter for consumer experience.

From this third study, we realized that it is important to make a difference between two concepts when comparing context studies: product experience and meal experience. Product experience has been described by [START_REF] Desmet | Framework of product experience[END_REF] as "all affective responses that can be experienced in humanproduct interaction" (p.13). These authors considered three dimensions of the product experience: aesthetic experience (perception), experience of meaning (cognitive processes), and emotional experience (affective phenomon) (Figure 11). When looking at context studies we may then consider that not only environmental or product-related variables may influence consumer hedonic evaluation. Variables such as the service or the management at the restaurant can also influence consumer experience (especially in restaurants) due to the mental representations consumer may have created through personal experiences.

General discussion readymade products or processed food such as canned or ready-to-heat dishes; whereas in small restaurants and gastronomic restaurants consumers expected to find homemade dishes made from local ingredients and seasonal products. Once again, consumers we interviewed related this to the value perceived. Moreover, they discussed about the different levels of quality of processed food and their acceptability towards those differences depending on the context of consumption. For example, in a gastronomic restaurant, consumers would not mind to have certain side dishes made from frozen ingredients as they considered the quality of those ingredients would be higher than the one in a workplace cafeteria. -Yet, it is important to make the difference consumers made between frozen fresh ingredients and frozen processed food -. It is here, when the relevance of certain contextual variables intervenes and could be related to the concept of situational-appropriateness mentioned in the previous point (2.1.1.). Food-related variables may have more "weight" in places where consumers already expect to find a certain level of food quality, whereas environmental-related variables may count more in other contexts. This means that each context may create a frame of reference from where consumers are going to evaluate food products. This reference frame could be associated to the concept of situational appropriateness that refers to the perceived degree of fit between products and different usage situations (Cardello, & Meiselman, 2018). Several studies conducted on situational appropriateness have shown that consumers associate different products to different eating situations and contexts, and those associations are influenced by cultural norms and expectations, as well as consumption habits (familiarity with the product) [START_REF] Arruiz | Degree of appropriateness and frequency of consumption of mayonnaise , ketchup , mustard and similar sauces in Argentina[END_REF]Cardello et al., 2000;Giacalone et al., 2015). Those studies could help to explain the differences we observed between the two regions comparison (Paris and Lyon) and the two types of population (students and non-students).

Therefore, when comparing context studies, we suggest to look at consumers' mental representations towards the studied contexts in order to set the frame of reference from where consumer's hedonic responses will be compared. It is also important to consider that contextual variables may not have the same relevance in different contexts so it may be difficult to determine the direct influence of specific contextual variables on consumer hedonic evaluation.

Prospect theory approach: evaluation task and reference points

The influence of the evaluation task on consumer hedonic responses

The role of the evaluation task has been widely explored in the fields of psychology and experimental economics (Harrisson & List, 2004). How consumers perceive and perform a task can help to explain the results obtained in an experiment. In sensory science, different measurement tools (questionnaires and scales) have been developed in order to assess consumer hedonic evaluation. Methods such as General discussion hedonic scaling, labeled magnitude scales, Just-About-Right Scales or CATA questions have been used showing controversial results on consumer's hedonic responses depending on the type of task performed [START_REF] Hein | Comparison of five common acceptance and preference methods[END_REF]Jaeger et al., 2013;Popper et al., 2004;Prescott et al., 2011). However, as it was described in the literature review (chapter 1 and 3), the role of the evaluation task has not been explored in natural consumption contexts.

Generally, when we evaluate a product, without any evaluation task demanded, we express a spontaneous and global judgement that usually corresponds to: "I like it", or "I do not like it". This could be interpreted as a synthetic evaluation. However, when we focus on the sensory attributes of the product: "it is not too salty", "it is too sweet", we perform a more analytical evaluation. The fact of introducing a questionnaire in natural conditions has already shown to have an impact on consumer behavior towards the task. However, how the type of evaluation task influences consumers' hedonic responses in natural conditions it was still unclear.

Chapter 8 presented a fourth study conducted in a university cafeteria where consumers' hedonic responses towards different products were assessed by using synthetic and analytical evaluation task.

Two different type of products were used: pizza with different degrees of culinary preparation (homemade, industrial and a mixed of the two) and bread that served as a control. Liking scores of the homemade pizza (the most liked version) were lower with the analytical task while the scores of the other two pizzas and the bread did not significantly change. This fourth study revealed that differences in task format may affect participants' responses to liking scores in the case of multicomponent products such as pizzas. The fact of asking participants to rate sensory attributes may influence their attention, and therefore their perception of dishes' attributes. However, this should be confirmed with other product categories, especially dishes served in eating contexts (such as restaurant, cafeterias, canteens) where different degrees of culinary preparation may be performed and are to be expected.

As we mentioned before (point 2.1), these results also suggest that consumers may differently evaluate standardized products (in the case of this study, bread) compared to those that need certain preparation in a natural consumption context (in the case of this study, pizza). The evaluation of the different sensory attributes in the analytical evaluation task showed that consumers differently rated the attributes of the three different pizzas, which could be related to the different degrees of culinary preparation involved and, the task performed. Nevertheless, it could be interesting to repeat this study in natural and also controlled conditions in order to observed the stability of the results within the same culinary preparation (for example, homemade). We observed that in the case of the standardized product, bread, similar results were obtained during the two days of study for both tasks, while in the case of the pizzas this was not possible. It could be then interesting to see if consumer hedonic responses towards multicomponent products are also constant within the same task or not.

General discussion

Moreover, even if consumers' expectations were not assessed in this study and no information was given about the culinary preparation, we could hypothesize that consumers did not expect to find a homemade pizza at the university cafeteria context. As we discussed in chapter 7, consumers do not associate this type of preparation to this type of context. Therefore, the fact of explicitly ask consumers about the sensory attributes of the homemade pizza may have increased consumers' attention towards the characteristics of the product. The sensory attributes perception may have contrasted with what consumers expected to find in the cafeteria, that is, the mixed pizza (frame of reference for consumers in this study) or readymade pizza, decreasing consumers' hedonic responses.

Conversely, when a more global question was asked (synthetic evaluation task), these mismatch between expectations and actual liking may did not have occurred.

This fourth study also revealed that not only liking scores differed depending on the task format, but also the final ranking of the products. Although consumers' preferences were not assessed in this study, looking at the global picture of the products evaluation (Figure 13), we observed that the ranking of the products changed depending on the evaluation task performed. This result could be explained by the difference in the number of consumers per condition but also, it suggest that the use of different evaluation task may entail different managerial decisions for industrials when products are tested in context studies. Additionally, it could be interesting to repeat this experiment by changing the order of sample presentation in both natural and controlled conditions. Even if a pure monadic presentation was carried out, consumers were familiar to this product, so they could have compared the readymade pizza of the last experimental week to the mixed pizza version from the previous week, and this, to the homemade one.

General discussion

It is possible that in natural consumption contexts, a synthetic evaluation task will be close to the natural and spontaneous consumer judgement we previously described. The fact of asking more questions about the product, may frame consumers' attention to particular characteristics of the product that in natural conditions consumers may not perceive. We could suggest that we "created" a sensory booth environment within the natural context of consumption. Thus, the question would be to know what is the point of performing a synthetic or analytical evaluation task in a natural consumption context where multiple contextual variables may influence consumer responses. Maybe, the fact of focus consumers' attention to the task, could reduce the bias set by environmental-related variables.

Nevertheless, the ecological validity expected to achieve in a natural consumption context could be compromised. Additionally, as we previously mentioned (point 2.1), some consumers did not appreciate the fact of answering a questionnaire while eating. So, the fact of answering a longer questionnaire could also influence consumer hedonic evaluation as previous studies have shown [START_REF] Earthy | Effect of question order on sensory perception[END_REF]Popper et al., 2004).

These results suggest that when different information is presented about the same issue (hedonic evaluation), different aspects of the outcomes may occur. This could be related to the notion of framing effects widely explored by psychologists and behavioral economics [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF]. As sensory scientists have done when comparing different measurement tools in controlled conditions, it could be interesting to know, how consumers in more natural conditions evaluate food products depending on the type of evaluation task. As Köster (2003) argued, we are not sure about how consumers understand a specific evaluation task. However, we try to increase the realism of consumer tests in order to ensure the ecological validity of the data. Thus, we suggest that further research on framing effects in more natural consumption contexts should be conducted in order to understand if consumers perform the evaluation task as they do in control conditions and, from a practical point of view, if consumers choices would differ depending on the formulation of the evaluation task in natural contexts.

Framework of reference on consumer hedonic evaluation

Consumer evaluation takes place within a context. Therefore, the context determines the reference on which consumers base their evaluation. However, it is still unknown what is the framework of reference when consumers evaluate a product in different contexts. The literature review (chapter 1)

showed that context effects have been widely studied in the fields of psychology and behavioral economics through Prospect theory. This theory posits that the outcomes of our decisions are defined by losses versus gains with respect to a reference point (Tversky & Kahneman, 1991).

General discussion

Reference points are considered as the status quo or current state from which consumers make the evaluation of outcomes [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF]. Outcomes that can be differently perceived if the reference point changes or is manipulated [START_REF] Jervis | The Implications of Prospect Theory for Human[END_REF], through expectations, norms, and social comparisons [START_REF] Tversky | Advances in Prospect Theory : Cumulative Representation of Uncertainty[END_REF]. According to that, we could imagine that this could occur when consumers evaluate or choose a product, and certain characteristics of it will be more or less easily accessible, determining the reference of evaluation.

The studies conducted in this thesis, suggested that consumption contexts set reference points from where consumers are going to evaluate a food. Moreover, we observed that consumers' expectations and beliefs towards a particular context are related to certain characteristics of the product, especially to the quality of ingredients and food process (homemade versus processed food). In the study performed in chapter 8, we also observed that consumers perceived the difference between three culinary preparations in a student cafeteria and that the results were in line with the results observed in the discussions groups (chapter 7), and the literature: homemade products are better considered than more processed food (GIRA Conseil, 2013). However, we did not know if this attention consumers place to those characteristics is the same in every context or for every product.

Therefore, considering that reference points can be manipulated by expectations, and expectations are built from mental representations, chapter 9 tried to explain how task-related framing effects modulate consumer hedonic evaluation. We wanted to explore if the framework of evaluation (reference dependence) could help to explain why some products seem to be more affected than others by context variations.

In order to answer this objective, two experimental studies (fifth and sixth) were conducted.

In the fifth study ("cakes study", chapter 9.2), we investigated the role of variations of preparation method (homemade and readymade) in setting reference points in different evaluation contexts (central location test (CLT) and restaurant). We hypothesized that expectations in association with context would induce a frame of reference for evaluation that would explain differences in sensitivity to context. In the sixth study ("quiche study", chapter 9.3), we investigated the influence of the type of information (consistent or inconsistent with consumers' expectations and beliefs) provided on food preparation and origin of ingredients on consumer hedonic evaluation to a product in a natural consumption context.

In the fifth study (chapter 9.2) we observed that consumer hedonic responses in the restaurant setting were higher, regardless of the product version. These results were in line with previous studies that reported lower liking scores in controlled conditions compare to natural consumption contexts (King et al., 2007;Meiselman et al., 2000). However, as the first study showed in chapter 5, this is not a constant result. This could be explained by the differences in the consumer population: in the first study (chapter 5), consumers were students of culinary arts (18-20 years old), whereas in this fifth General discussion study (chapter 9.2), consumers were adults among 30-60 years old. Or, this could be explained by the difference in product and meal experience related to consumers' expectations. The students in the first study (chapter 5), may have perceived the CLT product experience as something new, interesting and fun related to their "professional activity", while answering the questionnaire at the restaurant during lunch may be perceived as something uncomfortable to do due to time constraints. However, in this study (fifth study, chapter 9.2), consumers who evaluated the products at the restaurant may have perceived this as part of the meal experience, interesting and fun (also due to the characteristics of the "Living Lab" restaurant), while those who came to the CLT and were informed that they would have to evaluate a product in controlled conditions, may have perceived the product experience as something stressful or less fun due to the prior expectations. We could suggest that in this study people came to the CLT with a "lower" overall framework, and this could relatively impact consumer hedonic evaluation.

Besides, with could also note that information played a key role on consumer evaluation of the readymade version. This could be related to the fact that products with an overall 'high' reference score (homemade) seem less affected by variations of context than less appreciated products or products with more uncertainty as it could be the case for the readymade labelled product. As it has been shown in chapter 7, consumers are less prone to have this type of products (readymade or processed food) when eating out and negative attitudes have been reported towards them (GIRA Conseil, 2013). These negative attitudes may become more salient by the presence of information and directly impact consumer evaluation as previous studies have shown [START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Lee | Try It, You' ll Like It[END_REF][START_REF] Stolzenbach | Impact of product information and repeated exposure on consumer liking , sensory perception and concept associations of local apple juice[END_REF]. However, those effects were not observed for the homemade version as the presence of information did not increase consumers' hedonic responses what could be explained by the match between what they expected to have and what they actually had regardless of the context.

Finally, one of the most important results from this thesis was the significant effect the order of presentation (monadic sequential and pure monadic) on liking and on the fulfillment of expectations that we observed in the fourth and fifth study (chapter 8 and 9.2). This, reveals a possible contrast or disappointment when the homemade version was presented first. The order of sample presentation has shown to have an effect on consumer hedonic evaluation (Boutrolle et al., 2005(Boutrolle et al., , 2007)). However, this effect has not been further explored in natural consumption contexts. A logical explanation to that, is the fact that consumers do not usually taste two similar products one after another in natural consumption contexts. Conversely, they compare the product to a personal reference point what could correspond to the pure monadic mode (fourth study, chapter 8). In fifth study, we modulated the framework of evaluation and consumers compared two versions of a product in a monadic sequential mode. This could modulate the reference point of comparison from one product to another as well as

General discussion

with the products could help to explain those differences as previous studies have related unfamiliar products to a more context-dependent effect (Giacalone et al., 2015;Jaeger et al., 2017;[START_REF] Jaeger | Perceived situational appropriateness for foods and beverages: consumer segmentation and relationship with stated liking[END_REF]. Nevertheless, further research should be performed in order to understand the differences between standardized products and those that require a certain level of preparation, and contexts effects; including methodological aspects as the portion size and presentation. Recent research has been conducted with regards to the use of products as ingredients in the preparation of different dishes. In this type of studies, the same principle as in situational appropriateness is applied, but instead of measure the appropriateness of a product in a particular occasion, they measure the appropriateness of a product as ingredient on a recipe [START_REF] Spinelli | Global profile: Going beyond liking to better understand product experience[END_REF].

Consumers mindset

We underlined that consumers' mindset when coming to a consumer test differ from consumers' mindset when going to a restaurant, what may already influence the way in which consumers are going to perceive and evaluate a product. When consumers perform a hedonic evaluation in a controlled condition, we consider that consumers will have expectations towards it and that these expectations could modulate their evaluations. Besides, when comparing context studies, we consider that expectations towards a particular consumption context will influence consumer hedonic evaluation. However, we do not measure the expectations consumers may have toward the laboratory conditions. Therefore, we suggest that research should be conducted in this area in order to have a global picture regarding consumers' expectations towards all contexts, when comparing context studies.

Food value and consumer hedonic evaluation

The role of food value on consumer hedonic evaluation has risen different questions regarding the comparison between contexts studies. In general, food value is not addressed in controlled conditions, whereas in natural consumption contexts consumers usually pay for their food. The value perceived by the consumers has shown to influence product and meal experience (Ozdemir & Caliskan, 2014;[START_REF] Rozin | A field experiment to design healthier foods: Consumer valuation of butter production processes[END_REF]. The match between what consumers expect to have and what they obtain for a price, influence their food evaluation. For example, low quality food that yet meets expectations may be preferred to high quality food that doesn't. However, how can we accurately predict the match between expectations and actual experience regarding food value still needs further research.

Prospect theory and consumer hedonic evaluation

It has been shown that to study context effects, assessing interactions of sensory and non-sensory factors is crucial. However, to determine what impact does environment have on the liking of products is still unclear, as other factors such as the context itself and people may also influence. In this thesis,

General discussion

we decided to explore the mechanisms that may help to explain how and not why, consumer hedonic evaluation is affected by contexts effects. As it was enounced in the literature review (chapter 3), solid theoretical principles from disciplines such as psychology and behavioral economics could help to explain some of the questions sensory and consumer scientists arise regarding the effects of context on consumer hedonic evaluation. The use of Prospect Theory especially, the principles of reference points and loss-aversion, together with the notion of framing effects, have helped to explain, in part, the possible effects contexts may have on consumer hedonic evaluation through a theoretical framework.

Although I could not go too far in this research question, I started to look at aspects that have not been or little explored in the studying on contexts effects. If we want to understand how contexts influence consumer hedonic evaluation, we need to understand how consumers evaluate products in natural consumption contexts. And to do so, we need to understand how the actual evaluation task could influence consumer hedonic evaluation.

We have observed that depending on the evaluation task format, consumer hedonic evaluation changes, and this seems to be product-dependent. [START_REF] Boutrolle | Mesure de l'appréciation des aliments par les consommateurs : état des pratiques et propositions méthodologiques[END_REF], highlighted that differences in diagnostic questions already induced differences in consumer responses between CLT and HUT studies. As we mentioned before, further studies should be conducted with different product categories, especially dishes served in eating contexts where different degrees of culinary preparation may be performed and are to be expected. Moreover, the role of the evaluation task could be crucial for industrials and food caterers to understand how products behave in different contexts and the managerial decisions involved depending on the results obtained with the different tasks.

Regarding the framework of evaluation, we realized that consumers create reference points from contexts and products experiences. These reference points can be modulated by expectations and beliefs, social norms, etc. When looking at contexts studies, we realized that even if hedonic responses are needed as an indicator of performance for product development, they do not explain the meaning of the differences observed on consumer evaluation in contexts studies. Instead, expectations and beliefs towards contexts have shown to influence those hedonic responses by the modulation of consumers' reference points. Prospect theory lays the foundations from which contexts effects on consumer hedonic evaluation could be understood. By establishing consumers' common reference points for a context, and modulating those reference points through expectations and beliefs, we could try to determine how contexts effects modulate consumer hedonic evaluation. Behavioral economics applies the theory behind reference points to understand differences in consumer behavior, especially regarding consumer decision-making, through the use of framing effects [START_REF] Lagerkvist | A theoretical description and experimental exploration of tri-reference point theory with respect to food choice[END_REF], 2017;[START_REF] Uyang | Labeling context and reference point effects in models of food attribute demand[END_REF]. From a practical point of view, we want to know if consumers are going to like a product, but also if they are going to choose it over another product in a particular context. This relies on the question what is the relation between hedonic

General discussion responses and willingness to choose? We could then imagine a first step from where the hedonic responses of different products could be collected, setting a reference point. Then, by the use of framing effects, different contexts and/or experiences could be differently formulated (as evoked contexts do) by priming on consumers' beliefs and expectations. This may modulate consumers' reference points towards products depending on the given context. The deviation of the reference points between each context may then help how consumer hedonic evaluation changes from a theoretical framework. Furthermore, this could be also conducted in natural consumption contexts where real food value could be also addressed.

To conclude, regarding context effects on consumer hedonic evaluation, the question that still remains is: to what extent does the absence of realism invalidate the consumer hedonic data?

CONCLUSION

In this dissertation we examined how different contextual variables influenced consumer hedonic evaluation in context studies. The literature review showed that context influences consumer hedonic evaluation through different mechanisms implied by several contextual variables. Contextual variables that we classified according to the criteria used to define the ecological validity of an experiment: environment, product, consumer and task.

The lack of standardization in the way contextual variables should be used or interpreted in context studies is related to the lack of a theoretical framework behind those studies. Disciplines as psychology and behavioral economics, have further explored the effects of context from the perspective of Prospect Theory which considers the effects of context on consumer evaluation through the notion of framing effects and reference points. However, those effects have not been considered in context studies in the field of sensory and consumer science.

In this perspective, this thesis aimed to contribute to understand the conditions under which context affects consumer hedonic evaluation of food products. Through a multidisciplinary approach grounded in Prospect Theory [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF], we proposed a theoretical framework to explain the empirical observations about contexts effects on consumer hedonic evaluation, and to further formalize the effects of context to ensure a better reliability of consumer and sensory studies.

We first examined the advantages and disadvantages of studying consumer hedonic responses in natural consumption contexts. The lack of data about studies in these type of contexts difficult the understanding of context effects on consumer behavior and hedonic evaluation. A preliminary study phase was set. Two studies were conducted in different contexts and within different information conditions in order to address the effect of consumers' expectations and beliefs towards contexts and product-related variables. No differences on consumer hedonic responses among contexts was observed. The results suggested that the standardization of product-related variables (portion size and presentation) could contribute to reduce the effect of context on consumer hedonic evaluation.

Additionally, food-related information seemed to increase the consensus among consumers when evaluating a product in natural consumption context. However, this effect was context-dependent.

The second objective of this dissertation was to assess consumer mental representations about food in different contexts to explore how the different contextual variables were integrated in consumer experience. Twelve focus groups (n = 86) were conducted between Paris and Lyon, and students and non-students' population. Results showed that consumers have different mental representations about contexts and those are related to product-related variables. Food quality, conviviality and taste were Conclusion highlighted together as price as key elements of consumer experience. However, the ranking of these variables differed depending on the context of consumption. Moreover, differences were observed between regions and type of population due to gastronomic cultural and consumption habits differences.

Once we obtained a global picture of the effects of context on consumer hedonic evaluation; the third and fourth objective of this work were based on Prospect theory. The third objective of this dissertation was to assess the influence of different evaluation tasks on consumer hedonic evaluation in a natural consumption context. While studies in controlled conditions have observed differences in consumer hedonic responses depending on the task performed, the literature does not provide enough data on this issue. We compared two different evaluation tasks (synthetic and analytical) in a student cafeteria. Moreover, we tested the effect of the task on two different product categories: standardized product (bread) and a product subjected to three different degrees of culinary preparation (pizza:

homemade, readymade and mixed of both). Results revealed that differences in task format could affect consumers' hedonic responses in the case of multicomponent products such as pizzas. However, this results should be confirmed with other product categories, especially dishes served in eating contexts (such as restaurant, cafeterias, canteens) where different degrees of culinary preparation may be performed and are to be expected. Additionally, the ranking of the three pizzas also differed depending on the task format suggesting that different evaluation task may entail different managerial decisions for industrials when products are tested in context studies.

Finally, the last objective of this dissertation was to explore if the framework of evaluation (reference dependence) could help to explain why some products seem to be more affected than others by context variations. In order to address this objective, two experimental studies were conducted. In the first study we investigated the role of variations of preparation method (homemade and readymade) in setting reference points in different evaluation contexts. In the second study we investigated the influence of the type of information (consistent or inconsistent with consumers' expectations and beliefs) on consumer hedonic evaluation to a product in a natural consumption context. We hypothesized that expectations in link with context would induce a frame of reference for evaluation that would explain differences in sensitivity to context. The results showed that hedonic responses differed depending on the context and that those differences could be related to a "lower" overall framework of evaluation depending on the context. Moreover, the presence of information showed that products with an overall 'high' reference score seem less affected by variations of context than less appreciated products or products that induced more uncertainty. Those results suggested that prospect theory and particularly, reference dependence, may be an interesting way to look at consumers' mind-set when performing a context studies. By modulating this reference point or framework of evaluation we might be able to explain certain differences between contexts that may Conclusion not be related to the physical context itself but to the consumers' attitudes or prior experiences towards a particular context and served food.

Throughout this work, we investigated methodological and theoretical issues that had not been previously considered in the literature. However, we just open the door to further research in context studies by using a multidisciplinary approach grounded on psychology and behavioral economics:

Prospect Theory. We consider that the theoretical principles used in behavioral economics offer greatest insights about consumer evaluation methodologies for new product development and could help to improve the reliability of context studies.

This work only addresses a small part of a much larger research question that consumer and sensory

practitioners try to answer since 1992: to what extent does the absence of realism invalidate the consumer hedonic data in controlled conditions? (Meiselman, 1992, p. 50). En 2017, Jaeger et al. ont identifié la prise en compte du contexte parmi les perspectives les plus importantes pour l'avenir des sciences sensorielles et de la consommation (Jaeger et al., 2017). En règle générale, les tests hédoniques réalisés lors d'études consommateurs sont effectués dans des conditions contrôlées. Cependant, le manque de réalisme de ces tests a été associé à un manque de validité écologique de l'évaluation du consommateur (défini comme la mesure dans laquelle l'environnement expérimenté par le sujet dans une enquête scientifique possède les propriétés supposés ou assumés par l'investigateur [START_REF] Brofenbrenner | Toward an Experimental Ecology of Human Development[END_REF]) ce qui peut induire une fiabilité moindre des données. Ainsi, la généralisation des données issues de tests auprès de consommateurs dans des conditions contrôlées à des « vrais » contextes ou contextes « réels » est discutable (Köster, 2003).

Les nombreux échecs de lancement de nouveaux produits sur le marché ont été attribués à cette absence de conditions écologiques dans les tests réalisés par les consommateurs (Köster & Mojet, 2012a) [START_REF] Bernard | Do labels that convey minimal, redundant, or no information affect consumer perceptions and willingness to pay?[END_REF][START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF][START_REF] Lusk ; Schifferstein | en France, un pays qui peut différer dans la façon dont le consommateur perçoit et expérimente l'alimentation dans des contextes différents en raison de sa culture gastronomique[END_REF][START_REF] Mcfadden | Cognitive biases in the assimilation of scientific information on global warming and genetically modified food q[END_REF]. Le fait de souligner un aspect particulier d'un produit, oriente l'évaluation du consommateur sur ces caractéristiques qui deviennent plus saillantes. Considérant que le contexte de consommation ne peut être dissocié des attentes du consommateur et de ses croyances quant à l'expérience du produit, l'utilisation de l'information semblait être un bon outil pour évaluer cette possible interaction. De plus, cela nous a permis de déterminer si le consommateur percevait l'information de la même manière, en fonction du contexte. Cette thèse examine les conditions dans lesquelles le contexte affecte l'évaluation des produits. Ce travail s'appuie sur la théorie des perspectives, qui considère les effets du contexte sur le jugement à travers la notion de points de référence.

Standardisation des variables liées

Résultats et discussion

Les travaux visaient d'abord à comprendre comment les perceptions des consommateurs et leur évaluation des produits sont influencées par leurs représentations concernant les produits dans différents contextes de consommation. Une étude qualitative (12 groupes de discussion ; N = 86) a révélé que les croyances et les attentes des consommateurs à l'égard d'un contexte particulier sont associées à différents types de produits et de méthodes culinaires, et que les facteurs externes ont un poids différent selon le contexte de consommation.

Le deuxième objectif était de comprendre en quoi l'évaluation par les consommateurs d'un produit alimentaire dans des contextes naturels de consommation pouvait différer selon la nature de la tâche d'évaluation. Les évaluations hédoniques de produits présentant différents degrés de préparation culinaire (pain = contrôle ; pizza = fait maison, industriel et assemblé) ont été dfsdfsdf comparées (N = 457) entre deux tâches différentes lors d'une expérience conduite en cafétéria. Les résultats ont montré que les produits à plusieurs composants soumis à différents degrés de préparation culinaire (pizza fait maison) étaient en effet plus sensibles au type de tâche d'évaluation que des produits plus standardisés (pain).

Le dernier objectif de la thèse était d'explorer les facteurs contribuant à la formation de points de référence pour expliquer les influences contextuelles sur l'évaluation des consommateurs. Deux expériences ont comparé les évaluations hédoniques dans (i) deux contextes (CLT et restaurant ; N = 283) en condition informée et non informée sur les degrés de préparation culinaire d'un produit (cake salé) ; et (ii) dans un seul contexte (restaurant ; N = 114) en condition informée sur les degrés de préparation culinaire et l'origine des ingrédients (quiche) ; où les croyances et les attentes des consommateurs à l'égard des aliments servis changent. Les résultats ont montré que les effets de facteurs externes pouvaient être réduits par un contrôle minutieux des convictions et des attentes des consommateurs dans un contexte donné.

Cette thèse contribue à la compréhension des effets des contextes sur l'évaluation hédonique des consommateurs et propose un cadre théorique pour étudier ces effets à travers des points de référence. Les résultats pourraient être utiles pour élaborer des lignes directrices pour les industriels et chercheurs utilisant des évaluations hédoniques pour inclure le contexte de manière adéquate à chaque étape du développement du produit.

Title: Methodological insights to understand the effects of context on consumer hedonic evaluation of food products Keywords: context effects, hedonic evaluation, reference points, food preparation, expectations, information Abstract: Environmental factors modulate consumers' perception and in turn, consumers' evaluation of food in a given context, either directly or through context-induced beliefs and expectations. However, food products are usually evaluated in standardized conditions in an attempt to neutralize possible context effects on consumer evaluation. This questions the generalization of such measures to more natural consumption contexts.

The aim of this research was to examine the conditions under which context affects consumer evaluation of food products. This work is grounded in Prospect Theory, which considers the effects of context on judgement through the notion of reference points.

The first objective was to understand how consumer' experiences and subsequent product evaluations are influenced by consumers' representations about food in different consumption contexts. A qualitative study (12 focus groups; N =86) revealed that consumers' beliefs and expectations towards a particular context are intimately associated to different types of products and culinary methods, and that external factors have a different weight depending on the consumption context.

The second objective was to understand how consumers' hedonic responses in natural consumption contexts may differ depending on the type of evaluation task. The hedonic responses of products with different degrees of culinary preparation (bread = control; fffff pizza = homemade, industrial and mixed) were compared (N = 457) between two different tasks in a student cafeteria. The results showed that multicomponent products subjected to a different degrees of culinary preparation (homemade pizza) were indeed more sensitive to the type of evaluation task compared to more standardized products (bread).

The last objective of the thesis was to test hypotheses based on Prospect Theory to explain contextual influences on consumers' food evaluation. Two experiments compared hedonic evaluations in (i) two contexts (CLT and restaurant; N= 283), in blind and informed conditions about the degree of culinary preparation of a product (ham-olive cake); and (ii) in one context (restaurant; N = 114) in informed conditions about the degree of culinary preparation and origin of the ingredients (quiche); where consumers' beliefs and expectations towards the food served were modified. Results showed that the effects of external factors could be reduced through careful control of consumers' beliefs and expectations in a given context.

This thesis contributes to the understanding of context effects on consumer hedonic evaluation and it proposes a theoretical framework to investigate those effects by means of reference points. The results could be valuable to develop guidelines for industrials and researchers using hedonic evaluations to include context adequately at each stage of product development.

Figure 3 .

 3 Figure 3. Organization of the contextual variables that influence consumers' judgement and behavior.

  Emotions and mood have shown to influence the way in which products are perceived. Moreover, those feelings may change not only depending on the product but on the context as it occurs with consumers' expectations PART A: Literature review and Research Hypotheses and beliefs. Past experiences and product familiarity have also shown to be context-dependent.

Figure 4 .

 4 Figure 4. Example to explain reference-dependent (Retrieved from Kahneman, 2002).

Figure 5 .

 5 Figure 5. Illustration of loss-aversion theory (Retrieved from Tversky & Kahneman, 1991).

  PART A: Literature review and Research HypothesesDoes prospect theory help to explain / predict consumer responses' sensitivity to the context of evaluation in hedonic tests?Although prospect theory has not, to our knowledge, been applied to the study of context effects in consumer hedonic evaluation of food products in the field of sensory and consumer science, some works in those fields have discussed the use of this theory in the context of consumers' expectations and the confirmations or disconfirmations of expectations(Piqueras-Fiszman & Spence, 2015;[START_REF] Schifferstein | Asymmetry in the Disconfirmation of Expectations for Natural Yogurt[END_REF].

Figure 6 .

 6 Figure 6. Schematic representation of the source and predictions of Assimilation-Contrast Theory. The upper part gives the responses predicted by Assimilation, Contrast and Assimilation-Contrast Theory for a labelled product. The lower part shows the sections of the underlying, subjective continuum used in the latter theory to classify a stimulus after an expectation has been formed (Retrieved from Schifferstein et al., 1999).

Figure 7 .

 7 Figure 7. Schematic representation of the problematic.

Figure 8 .

 8 Figure 8. Summary of the research questions of the present thesis.

Figure 1 .

 1 Figure 1. Three context of study: 1) CLT; 2) evoked context; 3) Squared Flaveur Restaurant.

Figure 2 .

 2 Figure 2. Mean liking scores for all context in blind conditions. N refers to the numbers of participants per context.

Figure 3 .

 3 Figure 3. Mean hedonic scores for CLT and restaurant contexts in blind and informed conditions. N refers to the number of participants per condition.

PART 2 :Figure 1 .

 21 Figure 1. Setting of the Experimental café.

Figure 2 .

 2 Figure2. Menus offered to the conference attendees each day: a) menu card presented day 1: name of the dish; b) menu card presented day 2: information about the food preparation method (more appealing description); c) menu card presented day 3: information of food preparation method + origin + sustainable claim.

Figure 4 .

 4 Figure 4. Distribution of participants (%) per salad dish option and day (D). D1: name of the dish; D2: information about the food preparation method (more appealing description); D3: information of food preparation method + origin + sustainable claim.

  chicken (F (1, 42) = 0.266; p = 0.768); roasted salmon (F (1, 111) = 1.728; p = 0.182); Mediterranean tart (F (1, 31) = 0.983; p = 0.385).

Figure 5 .

 5 Figure5. Comparison of mean liking scores (± SEM) for the different protein dishes. D refers to the days of the study and condition (D1: name of the dish; D2: information about the food preparation method (more appealing description); D3: information of food preparation method + origin + sustainable claim); n refers to the number of participants who tested each dish each day.

Figure 6 .

 6 Figure 6.Comparison of mean liking scores (± SEM) for the different salad dishes. Letters above bars denote significant differences (p < 0.05) found between information conditions using Fisher (LSD)s post hoc analysis. D refers to the days of the study and conditions (D1: name of the dish; D2: information about the food preparation method (more appealing description); D3: information of food preparation method + origin + sustainable claim); n refers to the number of participants who tested each dish.

Figure 9 .

 9 Figure 9. Pictures of different consumption contexts

  a. Introduction and consent form signature: Consumers signed a consent form before the discussion started (see Appendix 4). b. Pictures classification game: Consumers, in subgroups of 2 or 3 people randomly created were asked to sort pictures of different consumption contexts following their own personal criteria. 24 pictures were presented including regular places of consumption: fast-food chains, tapas PART C. Consumer-related variables restaurants, semi-gastronomic restaurants, gastronomic restaurants, school or workplace cafeterias, international restaurants, brasseries, etc. We also included pictures of consumer tests in order to collect information about what consumers think of those particular contexts.The pictures were selected in order to lead the consumers to familiarize with the activity and as a start point for the discussion. After 10-15 minutes, each group presented their own classification and they started the discussion for approximately one hour and a half. c. Discussion: questions were asked by the moderator following the natural flow of the conversation. Three general themes were successively addressed: i. Consumption contexts: personal experiences ii. Relationship between food preparation and consumption contexts iii. Relationship between food preparation and culinary skills d. Short written questionnaire about eating out and culinary habits: filled out at the end of the session (see Appendix 5).

  PART C. Consumer-related variables b. Training level: some consumers questioned the expertise of chefs in institutional contexts and fast food chains. "Even at the training level, I do not think people are trained to make bulk homemade dishes. I think most of the chefs who are in the university restaurants are not necessarily very well trained, or they are not necessarily really good chefs, with enough training that allows them to make many homemade dishes and desserts for everyone". (man, G11).

"

  …go to a restaurant to eat 100% frozen products? no, thanks. I prefer to go to McDonald's because this is not what we expect when we go out." (woman, G2). c. Occasions: Consumers' food habits regarding different consumption contexts were associated to different occasions, company and time. "I can go to medium standard restaurants when I am with a friend or friends, and I can go to a big and fancy restaurant for an event, a birthday, a family party, because I want to have a service of quality. If I'm all alone and I have a PART C. Consumer-related variables craving, I go to McDonald's to have a burger, fries and a small beer and I love it too."

Figure 1 .

 1 Figure 1. Similarity analysis for the groups from Lyon.

Figure 2 .

 2 Figure 2. Similarity analysis for the groups from Paris.

Figure 3 .

 3 Figure 3. Similarity analysis for the groups of non-students.

Figure 4 .

 4 Figure 4. Similarity analysis for the groups of students.

Hypothesis 1 :

 1 context-related variables could have a different weight on consumer experience depending on the contexts.

  at the staff and student cafeteria of the Ecole Central of Lyon, France. Each evaluation was performed with a week apart. No information was given about the different versions of the pizza nor about the products concerned by the study and the cafeteria operated as usual without any change introduced. Participants arrived at the cafeteria from 11h30 to 14h00. The staff and students have the possibility to create their own lunch meal by choosing among three or four starters,

Figure 1 .

 1 Figure 1. Mean overall liking scores (and SEM) for the bread sample in the synthetic (overall liking only) and the analytical (overall liking plus attributes) groups. n refers to the number of participants in each testing condition. n.s. = not significant.

Figure 2A .

 2A Figure 2A. Mean overall liking scores (and SEM) for the different pizza versions (homemade, mixed and readymade) in the synthetic (overall liking only) and the analytical (overall liking plus attributes) groups. n refers to the number of participants in each testing condition; n.s. = not significant; ** = p< 0.01. B. Rank order of the different pizza versions for the most liked to least liked according to each evaluation task. Letters above products denote significant differences (p < 0.05) found between each culinary preparation using post hoc LSD test.

2 .

 2 Regarding the lemon pie, the three lemon pie versions (homemade, mixed and readymade version) were validated with the chefs previous the performance of the study as well as the dates for the experiment. The recipes were set by considering the ingredients of the readymade version. Unfortunately, during the three weeks of experiment, the supplier of the readymade lemon pie changed, changing the initial recipe of the pie. Moreover, differences in the recipes were made during the culinary preparation of the homemade and mixed lemon pie version which hindered the comparison among the three versions of lemon pie.

  a. two contexts and two products were tested b. the fulfillment of consumers' expectations was assessed c. no value for money was addressed 2. In the second study: a. One context and one product were tested; just information change b. Expectations were assessed prior consumption c. Value for money was addressed Those works are presented in Article 4 (accepted); and Article 5 (in writing).

Figure 1 .

 1 Figure 1. Ham-olives cake (Presentation of the product at the restaurant).

Figure 4 .

 4 Figure 4. Comparison of mean liking scores (± SEM) for the two product versions and the two information conditions (informed, non-informed), regardless of the setting and order of presentation. Letters above bars denote significant differences (p < 0.05) found between information conditions using Tukey's test for pair-wise comparison. Participants who tested the homemade product in informed condition (n = 147) are the same of those who tested the readymade product in the informed condition and same for the non-informed condition (n = 136).

Figure 9 .

 9 Figure 9. Distribution of liking scores with respect to their fulfillment of expectations. Respondents were

  and smooth. Then the dough was filmed and kept for one hour in cold storage at 4°C. The dough was put between two sheets of greaseproof papers and flatten out with a rolling pin to 1.5 mm thickness and was kept 10 minutes in cold storage 4°C. Then the dough was shaped in the tartlet molds, 8 cm in diameter on 1.5 cm in height. The tartlets rested for 10 minutes in cold storage and then were baked for 17 minutes in a preheated oven at 150°C with medium ventilation on and open exhaust.

Figure 1 .

 1 Figure 1. Tomato and goat cheese tartlet.

Figure 2 .

 2 Figure 2. Schema of the tartlet ingredients.

Figure 4 .

 4 Figure 4. Mean overall liking scores (and SEM) for the tartlets depending whether consistent or inconsistent information was given. n refers to the number of participants in each testing condition; * = p< 0.05.

Figure 5 .

 5 Figure 5. Mean intensity scores (and SEM) for each sensory attribute depending whether consistent or inconsistent information was given; ** = p< 0.01; n.s. = non-significant; N = number of participants in each testing condition.

Figure 6 .

 6 Figure 6. Mean intensity scores (and SEM) for each sensory attribute depending whether consistent or inconsistent information was given; ** = p< 0.01; n.s. = non-significant; N = number of participants in each testing condition.

Figure 11 .

 11 Figure 11. Framework of product experience (Retrieved from Desmet & Hekkert, 2007).

Figure 12 .

 12 Figure 12. Five Aspects of the Meal Model (Retrieved from Edwards & Gustafsson, 2008).

Figure 13 .

 13 Figure 13. Liking scores of the three pizza versions depending on the evaluation task format (n refers to the number of participants per condition).

6 . 7 .Figure 1 .

 671 Figure 1. Effects of context on consumers' perception (Retrieved from Kahneman, 2002). ...................

Figure 2 .

 2 Figure 2. "Essential factors that influence eating and drinking behavior and food choice" according to Mojet ......................................................................................................................................................

Figure 3 .

 3 Figure 3. Organization of the contextual variables that influence consumers' judgement and behavior. .............................................................................................................................................................

Figure 4 .

 4 Figure 4. Example to explain reference-dependent (Retrieved from Kahneman, 2002). ......................

Figure 5 .

 5 Figure 5. Illustration of loss-aversion theory (Retrieved from Tversky & Kahneman, 1991). ..............

Figure 6 .

 6 Figure 6. Schematic representation of the source and predictions of Assimilation-Contrast Theory. The upper part gives the responses predicted by Assimilation, Contrast and Assimilation-Contrast Theory for a labelled product. The lower part shows the sections of the underlying, subjective continuum used in the latter theory to classify a stimulus after an expectation has been formed (Retrieved from Schifferstein et al., 1999). ....................................................................................................................

Figure 7 .

 7 Figure 7. Schematic representation of the problematic. ........................................................................

Figure 8 .

 8 Figure 8. Summary of the research questions of the present thesis. ......................................................

Figure 9 .

 9 Figure 9. Pictures of different consumption contexts ...........................................................................

Figure 10 .

 10 Figure 10. Mean ratings of overall flavor liking (and SEM) for a tea sample when comparing synthetic (overall liking only) and two analytical (overall liking plus attributes) evaluation tasks (Retrieved from Prescott et al., 2011). ..........................................................................................................................

Figure 11 .

 11 Figure 11. Framework of product experience (Retrieved from Desmet & Hekkert, 2007). ................

Figure 12 .

 12 Figure 12. Five Aspects of the Meal Model (Retrieved from Edwards & Gustafsson, 2008). ............

Figure 13 .

 13 Figure 13. Liking scores of the three pizza versions depending on the evaluation task format (n refers to the number of participants per condition). ......................................................................................

3. 1 .

 1 Ce chapitre visait à identifier comment les variables liées à l'environnement influenceraient l'évaluation hédonique du consommateur lorsque les variables liées au produit seraient standardisées (quantité d'aliment et présentation). Nous avons évalué le niveau d'appréciation des consommateurs (n = 151) dans trois contextes différents (test de localisation central (CLT) ; contexte évoqué ; restaurant). De plus, différentes conditions d'information ont été testées (aveugle et informé) concernant le mode Résumé en Français étudiants ont décrit ces contextes comme des environnements froids. La décoration a été évoquée et évaluée positivement lorsque les consommateurs ont discuté de la restauration gastronomique, alors que ce n'était pas le cas pour les lieux de travail, les cantines scolaires et les chaînes de restauration rapide. En ce qui concerne les tests de consommation, les consommateurs ont montré une attitude négative à l'égard de ces contextes lorsqu'ils ont discuté de l'expérience alimentaire. Les consommateurs ont convenu que ce contexte ne peut être décrit ou considéré comme une expérience de repas en raison du manque de convivialité et du service.Des différences dans les variables liées aux produits ont été observées entre les contextes de consommation et elles ont été associées aux attentes et aux croyances des consommateurs à l'égard des aliments servis. Les consommateurs ont ouvert une discussion importante entre les produits faits maison et les produits industriels. Les produits faits maison étaient associés à des ingrédients naturels, locaux, saisonniers et savoureux. Alors que les produits industriels étaient associés à l'utilisation d'ingrédients chimiques, à des scandales dans l'industrie alimentaire et à des ingrédients malsains. Les consommateurs ont également associé l'utilisation de ces deux types de produits et de processus à différents contextes de consommation en fonction du volume et du prix de l'offre alimentaire.L'analyse lexicométrique a permis d'identifier des différences entre les groupes de Paris et de Lyon.Les groupes parisiens étaient plus concentrés sur différentes expériences de repas liées à la décoration et au prix des menus. À l'inverse, les groupes lyonnais étaient davantage axés sur les variables liées au produit, telles que la préparation des aliments et l'utilisation d'ingrédients. Les groupes issus des deux régions ont convenu de l'importance de la convivialité dans l'expérience du consommateur. Comme dans le cas de la comparaison des régions, l'analyse lexicométrique a montré des différences dans le discours des étudiants et des non-étudiants lorsqu'ils décrivaient des expériences de repas. Les groupes d'étudiants étaient plus concentrés sur les expériences affectives et le prix que sur les aliments pris au restaurant tandis que les groupes de non étudiants se concentrent davantage sur la qualité des aliments.De plus, des différences en termes de compétences culinaires ont été observées entre les deux populations, ce qui peut expliquer la différence en termes d'expérience de consommation entre les groupes d'étudiants et de non-étudiants.La présente étude montre que les représentations mentales du consommateur concernant les aliments dans différents contextes de consommation impliquent différentes variables contextuelles. Les représentations du consommateur peuvent impliquer davantage de variables liées aux produits dans certains contextes ou davantage de variables environnementalestelles que la convivialité du moment partagé entre amis -dans d'autres. Cela révèle que, lors de la comparaison d'études contextuelles, l'évaluation hédonique du consommateur peut être affectée non seulement par la présence de variables contextuelles, mais également par la manière dont ces variables sont intégrées et influencent l'expérience du consommateur.Résumé en FrançaisLa présente étude montre que les informations relatives aux produits jouent un rôle clé dans le niveau d'appréciation du consommateur, quels que soient les effets du contexte. Cet effet pourrait être associé à la modification des points de référence du consommateur par ses croyances et / ou ses attentes à l'égard de caractéristiques de produits spécifiques dans un contexte donné. Les résultats suggèrent que le fait de prendre en compte ces facteurs liés au consommateur pourrait aider à expliquer certaines différences entre les études de contexte pouvant aller au-delà de l'environnement physique. De plus, un effet significatif de l'ordre de présentation de l'échantillon a été observé dans des conditions à la fois non informées et informées. Ce résultat doit être souligné car, dans les contextes de consommation naturelle, le consommateur ne goût généralement pas deux versions d'un produit comme il le fait lors de tests de consommation. Cette comparaison directe entre produits peut entraîner des décisions erronées du point de vue managérial lors du lancement du produit car les caractéristiques du premier produit testé peuvent servir de référence pour le second produit évalué.3. Associationsentre les attentes et les réponses hédoniques au restaurant : le rôle de l'information (étude « quiche ») Objectifs et méthodes Le but de cette étude était d'examiner l'influence du type d'information fournie sur la préparation des aliments et l'origine des ingrédients sur le niveau d'appréciation du consommateur sur un produit dans un contexte de consommation naturelle. Les attentes et les croyances des consommateurs (n = 114) à l'égard d'un contexte spécifique (restaurant), ainsi que le niveau d'appréciation de ces consommateurs dans ce restaurant spécifique ont été évaluées. En outre, deux conditions d'information différentes ont été testées en fonction des attentes des consommateurs. Les hypothèses suivantes ont été formulées :  Hypothèse 1 : Les attentes et les croyances des consommateurs à l'égard de la nourriture dans un contexte particulier aideraient à expliquer le niveau d'appréciation des consommateurs.  Hypothèse 2 : Une information cohérente avec les attentes et les croyances des consommateurs augmenterait le niveau d'appréciation des consommateurs par rapport à une information incohérente.  Hypothèse 3 : Des facteurs liés à l'alimentation impacteraient la satisfaction globale des consommateurs.

  Les résultats d'un sondage en ligne sur les attentes et les croyances des consommateurs à l'égard des aliments servis au restaurant ont permis d'expliquer leur niveau d'appréciation lorsque différents types soulevé le fait que l'évaluation hédonique du consommateur peut être affectée non seulement par la présence de variables contextuelles, mais également par la manière dont ces variables sont intégrées dans l'expérience du consommateur. En outre, nous avons observé que l'état du consommateur lorsqu'il est dans un test dans des conditions contrôlées peut différer de celui qui va au restaurant, ce qui pourrait déjà influer la façon dont le consommateur va percevoir et évaluer un produit. En fait, chaque contexte peut créer un cadre de référence à partir duquel le consommateur va évaluer les produits. Nous avons aussi constaté que les différences dans la tâche d'évaluation peuvent affecter le niveau d'appréciation du consommateur dans le cas de produits à plusieurs composants (pizza) et que cela peut impliquer différentes décisions de gestion pour les industriels lorsque les produits sont testés dans des études de contexte. Finalement ce travail a mis l'accent sur le rôle des attentes et des croyances du consommateur vis-à-vis du contexte de consommation en utilisant de l'information afin de moduler le point de référence crée par le consommateur.Cette thèse ouvre la porte à d'autres recherches sur les études de contexte en utilisant une approche multidisciplinaire fondée sur la psychologie et l'économie comportementale : la théorie des perspectives. Nous considérons que les principes théoriques utilisés en économie comportementale offrent un éclairage précieux sur les méthodologies d'évaluation du consommateur pour le développement de nouveaux produits et pourraient contribuer à améliorer la fiabilité des études de contexte.Ce travail n'aborde qu'une petite partie d'une question de recherche beaucoup plus vaste à laquelle tentent de répondre les chercheurs et les praticiens de l'évaluation sensorielle depuis 1992 : dans quelle mesure l'absence de réalisme invalide-t-elle les données hédoniques du consommateur dans des conditions contrôlées ? Titre : Propositions méthodologiques pour comprendre les effets du contexte sur l'appréciation des aliments par les consommateurs Mots clés : effets de contexte, évaluation hédonique, points de référence, préparation des aliments, attentes, information Résumé : Le contexte de consommation module la perception des aliments par les consommateurs et leur évaluation, soit directement soit par le biais de croyances et d'attentes induites par le contexte. Parallèlement, les méthodologies d'évaluation des produits alimentaires requièrent souvent des conditions standardisées afin de tenter de neutraliser ces éventuels effets de contexte. Mais ce gain en contrôle peut remettre en question la généralisation des mesures obtenues à des contextes naturels de consommation.

Significant effect of group size on meal duration in

	A. Galiñanes Plaza et al. A. Galiñanes Plaza et al.																											Food Quality and Preference 73 (2019) 226-247 Food Quality and Preference 73 (2019) 226-247
				Comments		Ecological validity and external	validity may have been ensured	because no changes were done in	the contexts and the regular task	(eat) was not affected	No food type comparison		The tested canned food may be	unfamiliar to the UK tested	population.	The nature of the task	(questionnaire distribution and	number of questions) differed	between and within contexts.	Participants in the lab condition	were in a very specific context and	mood state (students in attendance	to take a final exam)	Ecological validity and external	validity is ensured because no	changes were done in the contexts			Food preparation is context	dependent; therefore, acceptability	may differ from one context to	another due to sensory properties	modification.Contexts also differed	on service style, dinning, choice,	etc. = > Ecological validity is	ensured however results may not	be comparable across contexts	(continued on next page)
				Results		Meals eaten with other people	were larger and longer compared	to meals eaten alone. Meals eaten	with spouse and family were larger	and eaten faster, while meals eaten	with friends were larger and of	longer duration	Hedonic scores were 1 point	higher in the	restaurant > cafeteria. Regarding	hedonic attributes (texture, flavor,	color), ratings were higher in the	restaurant > cafeteria ones							the three settings,	however the effect was smaller in	the fast-food setting		Contexts affected acceptability	ratings: different scores were	obtained as regards product sensory	attributes (appearance, taste and	texture as well as satiety)
	Table 2	Summary of 20 context studies (using a) global approach, b) separated variable approach and c) global and separated variable approach).	a) Global approach	Study Studied Studied factor Selection of participants Nature of the Experimental Evaluation task	response product environment	de Castro (1994) Food intake Social 515 participants Regular meals Natural Food diary for 7 consecutive days: what	facilitation Participants were pre-consumption was eaten or drunk, time, amount,	recruited and contexts preparation method, type and gender of	remunerated people eating with. Hunger, degree of	Between-group design elation and anxiety ratings			Meiselman et al. Food Eating Cross-cultural study: • Menu based (2000) acceptance location 74 and 125 participants on canned • Training restaurant vs Food acceptance on a 9-point hedonic scale (UK)	(UK data) food • Menu main Participants were recruited for all locations dish Chicken Student cafeteria (UK); • Training rest. vs except sensory laboratory fettuccine Food lab vs Food attributes (flavor, texture, color, overall rating) on a 7-point hedonic scale (USA)	Between-group design Alfredo cafeteria (USA)					Bell and Pliner Meal duration Number of 1124 regular clients Regular meals • Worksite (2003) people at the Participants were cafeteria • Moderately table unaware of the study and not remunerated priced Purely observational No questionnaire	Between-group design restaurant • Fast-food restaurant	Edwards et al. Food Eating Participants: Chicken à la King Ten locations, Demographic	(2003) acceptability location Army training camp: 44 • University staff refectory/ 38 • Private boarding school: 88 • Freshman's buffet: 83 • Private party: 78 • Residential home (elderly): 43 • Student refectory: 33 • Day care center (elderly): 33 • University 4-star restaurant: 19 • Hotel 4-star restaurant: 32 and Rice representing different types of food service situations questionnaire + appearance, texture, taste and overall acceptability ratings on a 9-point scale + satiety ratings on a 6-point scale	Participants were	unaware of the current	study and not	remunerated	Between-group design
																										229 230

Table 2 (continued) a) Global approach Study

 2

	Comments
	Results
	Evaluation task		Overall liking on a 9-point hedonic
	Experimental	environment	• Central Location Test (CLT) • Home Use Test (HUT)
	Nature of the	product	5 apple juices	with different	sugar	concentrations
	Studied factor Selection of participants		Eating 35 elderly people	location 33 young people	Participants were	recruited	Between and within-	group design
	Studied	response	Predictive	value of	hedonic test
			Kozlowska et al.	(2003)

scales Context do not have a significant effect on hedonic scores even

	The nature of the product differs	among contexts (50 ml v 150 ml) as	regards the eating reference unit.	Scope for choice differs across	contexts, although it may be key to	ecological validity	The evaluation task differs among	contexts:	participants answer questionnaires	at different times (HUT at the end	of the day as a recall) what could	affect the attention participants put	on the product and therefore, on	the final hedonic score	The evaluation task differed	between contexts (time for	evaluation);Ecological validity of	HUT may depend on both the	environment and the task itself	(natural product consumption)
		if	higher scores were obtained at home	than in laboratory.	Poor prediction of laboratory	scores of juice consumption									Products got higher scores at the	HUT. The influence of the method	used depends on the type of product	(how products are usually eaten)	Pure monadic were slightly higher	than monadic sequential scores	Children chose significantly more	often the familiar version of the dish	when no information was given The	addition of a descriptive
															Overall liking scores on a 10-point	hedonic scale.	CLT: 2 products evaluated during 1	session	HUT: After one week of testing	participants got the second product and	repeated the same task	Chef give or not information about the	vegetable options Food choice at lunch	time
															• CLT • HUT				Three school	canteens:	School 1: 140 • School 2: 113 • School 3: 111
															2 variants of each	product: • Milk beverage • Salted crackers • Sparkling water	Products were	sequentially	presented	Carrot and	broccoli dishes
															Participants: regular users	of the tested products • Study 1: 240/context • Study 2: 240/context • Study 3: 160/context Participants were	recruited in-situ (CLT) or	pre-recruited by phone	(HUT)	Between-group design	Participants: • Non label: 125 • Basic label: 116 • Moderated Label: 131 Participants were	recruited	Between-group design
															Hedonic scores Eating	location	Product type				Food choice Labelling
															Boutrolle et al.	(2007)					Morizet, Depezay,	Combris,	Picard, and	Giboreau	(2012)

label led to an increased frequency of choice for the new vegetable dish for carrots

	A. Galiñanes Plaza et al.						Food Quality and Preference 73 (2019) 226-247
	Ecological validity is ensured as no	contextual variable is highly	modified. Only the information is	manipulated	only, and not for broccoli	Evaluation task Results Comments		Participants taste the 4 wines at Sensory differences among Sensory stimuli differ	each time and were asked to wines and contexts when the wine is tested	rate their liking on a 9-point significantly influenced liking together with foods.	hedonic scale scores (same size effect) Using a reception room	Food accompaniment had a allowed social	positive effect on liking interaction and food	scores accompaniment in a	natural way	(continued on next page)
						Experimental environment		4 contexts: • Laboratory: with/without food • Reception room: with /without food
						Nature of the product		Eight different	wines + dummy wine	Food accompaniment:	crackers with cheese,	carrots and broccoli with	dip and tortilla chips	with mild salsa
						Selection of	participants	55 participants:	likers of wine	Participants were	pre-recruited	Within-group	design
						Studied factor		Eating location	Food	accompaniment
					b) Separated variable approach	Study Studied	response	Hersleth et al. Liking	(2003)
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Table 2 (continued) b) Separated variable approach Study

 2

	Comments
	Results		Meal situation had a	strongest positive
	Evaluation task		Overall liking for the entire	meal + overall liking for each	meal component on a 9-	pointstructured hedonic	scaleDemographic information
	Experimental environment		6 contexts: • T1: Laboratory + individual items • T2: Laboratory + meal • T3: Laboratory + meal + social interaction • T4: Mock restaurant + meal + social	interaction • T5: Mock restaurant + meal + social	interaction + choice • T6: Restaurant
	Nature of the product		Side salad with dressing	Small pizza	Iced tea	Each component has two	flavor variants
	Selection of	participants	Participants: regular	consumer of the	tested products • Test 1: 104 • Test 2: 93 • Test 3: 106 • Test 4: 106 • Test 5: 101 • Test 6: 35 Participants were	recruited (CLT)	and/or contacted by	phone or	advertisements at	the local offices	(Test 3-5)	Between-within	group design
	Studied factor		Social interaction	Eating location	Choice
	Studied	response	Food	acceptability
			King et al.	(2004)

effect on tea and salad; social interaction negatively affected pizza hedonic scores; eating location had a weak but positive effect on pizza and tea and a negative effect on salad; and choice had a positive effect on salad

	The number of	participants varied a lot	from on context to	another (from 35 to	106)	The nature of the	product differs from one	context to another	(meal versus individual	meal components) as	well as the preparation	method because of	equipment differences	(CLT vs Restaurant).	This limits the	comparison between	hedonic scores obtained	in different contexts.	The evaluation task	implied by one context	(questionnaire	distribution, choice	option, etc.) contributes	positively to ecological	validity in real and	recreated restaurant,	but is not applied to the	standard CLT
																												Portion size estimation on a	portion size scale
																												4 contexts: • T1: Laboratory + meal • T2: Mock restaurant + meal + social	interaction • T3: Mock restaurant + meal + social	interaction + silver cutlery • T4: Mock restaurant + meal + social	interaction + silver	cutlery + choice
																												Pizza + salad + tea: 2	variants of each product
																												Participants: regular	consumer of the	tested products • Test 1: 93 • Test 2: 106 • Test 3: 106 • Test 4: 101 Participants were	pre-recruited	Between-within	group design
																												Social interaction	Eating location	Cutlery	Choice
																												Food	consumption
																												Weber et al.	(2004)

Salad consumption was higher when there was a choice of dressings in an enhanced environment. Pizza and tea consumption were higher in an enhanced restaurant-like environment. Social interaction alone has no impact on food consumption

	A. Galiñanes Plaza et al.							Food Quality and Preference 73 (2019) 226-247
	Participants have time	to eat and then answer	the questionnaire in all	context. Social	facilitation and choice	may increase ecological	validity	(continued on next page)
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Table 2 (continued) b) Separated variable approach Study

 2

	Comments		Product experience	differs between contexts	due to the possibility to	eat the cheese together	with other products at	the HUT (bread, crisp	bread, biscuits) so the	evaluations may not be	comparable.	The evaluation task	differed between	contexts (time for	evaluation); Ecological	validity of HUT may	depend on both the	environment and the	task itself (natural	product consumption)
	Results		No differences among	contexts and social	facilitation
	Evaluation task		Overall liking on a 9-point	hedonic scale + Questionnaire	in HUT about social interaction,	food eaten together with and	beverages													Food dairy before the	test + Appetite and mood	ratings on VAS + eat	product + recall how much	they had eaten using	photographs of 6 possible	portion size
	Experimental environment		3 contexts: • Laboratory • Club house of a soccer team • HUT													3 contexts: • T1: Laboratory • T2: Laboratory + TV • T3: Laboratory + negative social facilitation • T4: Laboratory + positive social facilitation
	Nature of the product		Hard and semi-hard	Norwegian cheeses																Different type of	products: bread rolls,	potato crisps, fresh green	salad, etc.
	Selection of	participants	87 participants:	regular cheese	consumers	Participants were	pre-recruited	Within-group	design											37 participants	Participants were	pre-recruited and	remunerated	Within-group	design
	Studied factor		Eating	locationSocial	facilitationMeal	accompaniments														Social facilitation	Relation among	participants
	Studied	response	Food	acceptance																Food intake
			Hersleth et al.	(2005)																Hetherington	et al.	(2006)

Energy intake was significantly enhanced by presence of familiar others and watching TV

	A. Galiñanes Plaza et al.																	Food Quality and Preference 73 (2019) 226-247
	The experimental	environment at T2 and	T4 may have influence	the evaluation task	increasing the	ecological validity of	the results as regards	consumers' intake.	Consumers may have	experienced a natural	consumption situation	Social facilitation and	meal occasions are	confounding variables	which can limit the	comparison between	contexts	(continued on next page)
												Music increased food and	drink intake and longer	meal duration. No significant	differences were found in	music speed or volume
												Food diary: amount and type of	eaten food, where, when with	whom, for how long, presence	of music, music speed and	volume on a 7-point scale
												Natural consumption contexts
												Food and drink intake of	7 consecutive days
												78 participants	Participants were	pre-recruited	Within-group	design
												Music
												Food intake	and meal	duration
												Stroebele and	de Castro	(2006)
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Table 2 (continued) b) Separated variable approach Study

 2

	Comments		The number of	participants highly	differs among contexts.	The nature of the	product differs from one	context to another	(portion size and	preparation). The	evaluation task differs	from T1 and T2	compares to T3	(whereas in T1 and T2	questionnaires were	presented at the	beginning of the meal in	T3 each product was	accompanied by the	specific questionnaires).	In this case higher	number of questions	were presented on T1	and T2 which may	could affect the	evaluation task
	Results		Location and food choice	had the strongest positive	effects on acceptance	ratings, while social	facilitation and enhanced	environment had no	significant effect on the	acceptability scores
	Evaluation task		Overall liking on a 9-point	structured hedonic scale (just	on CLT) + overall rating on a 6-	point structured hedonic scale																				Familiarity	questionnaire + ranking	test + testing and rating with 3	smiley faces (like, neutral,	dislike) + attributes	rating + preference ranking
	Experimental environment		3 contexts: • T1: CLT • T2: national Italian chain restaurant • T3: nation-wide in-store satisfaction survey in the same	chain restaurant																	Restaurant
	Nature of the product		• Iced tea • tossed salad with Italian dressing • garlic bread sticks • cannelloni with meat filling • meat lasagna																Carrots and French	beans: • mashed • steamed • boiled • stir-fried • grilled • deep-fried
	Selection of	participants	Participants: regular	consumers of the	tested product • Test 1: 74 • Test 2: 83 • Test 3: 386 Participants were	pre-recruited on test	1 and 2	Between-group	design													116 participants: • 46: 4-6ys • 25: 7-8ys • 23: 11-12ys • 22: 18-25ys Participants were	pre-recruited	Between-group	design
	Studied factor		Meal situation	Social interaction	Eating location	Choice																				Preparation	method
	Studied	response	Food	acceptability																						Liking
			King et al.	(2007)																						Zeinstra et al.	(2010)

Vegetable liking was related to a uniform surface and the typical vegetable taste.

	Small number of	participants.	In spite of effort to	conduct the test in an	experimental	restaurant, children	were seating alone	which may not have	been representative of a	regular lunch at school
				Brown coloring and a granular	texture were negatively	related				Mousse was perceived more	intense
										Taste one spoonful of the	sample and rate perceived	sweetness, flavor intensity, and	quality of the strawberry	mousse on an unstructured 10-	cm-long scales + liking on a 9-	point hedonic scale
										Laboratory: • Study 1: white vs black dishes • Study 2: triangular vs squared vs rounded
										Strawberry mouse
										Participants: • Study 1: 53 • Study 2: 51 Participants were	recruited	Within-group	design
										Product	presentation:	shape and color of	the plate
										Food	perception
										Piqueras-	Fiszman,	Alcaide,	Roura, and	Spence	(2012)

and sweeter in a white plate than in a black plate. The shape did not affect

	A. Galiñanes Plaza et al.		Food Quality and Preference 73 (2019) 226-247
	The nature of the	product/task differs	between a dessert	spoonful and a dessert	in terms of reference	unit	Ecological validity	could be questioned	since participants did	not know each	other.However,	evaluating croissants	with a drink is closer to	usual eating habits		(continued on next page)
							Social interaction negatively	affected all the liking scores	when compared to the control	groupSocial + drink	accompaniments seemed to	increase hedonic scores
							Overall liking + attribute liking	(appearance, odor, flavor, taste	and texture.) on a 9-point	hedonic scales Freshness on a 9-	point scale
							3 contexts: • T1: Laboratory • T2: Laboratory + social facilitation • T3: Laboratory + social facilitation + drink options
							5 frozen croissants
							Participants: regular	consumers of the	tested product • Test 1: 32 • Test 2: 33 • Test 3: 30 Participants were	pre-recruited	Between-group	design
							Social interaction	Drink	accompaniments
							Food	acceptability
							Di Monaco et al.	(2014)
	234

Table 2 (continued) b) Separated variable approach Study

 2

	Comments		Even in contexts	designed to be realistic,	the task differed from	natural situation, and	participants were not	allowed to talk and they	did not have the	possibility to select	their meal which may	affect the ecological	validity of the data
	Results		Appearance was higher	rated on the gourmet setting	as well as the willingness to	eat in realistic contexts	whereas in the laboratory the	table setting did not affect the	scores Intake differs	depending on the context	(laboratory < realistic	context) and table setting	(gourmet < home and plastic	tray)
	Evaluation task		Hunger status on a 9-point	Likert scale before and after	eating • Before eating: Impression of the appearance of the table	setting on a 9-point hedonic	scale + the willingness to	eat on a 9-point Likert scale • After eating: overall flavor and overall impression of	the served food on two 9-	point hedonic	scales + portion size	impression on a 9-point	Likert scale
	Experimental environment		2 contexts: • T1: Laboratory • T2: More realistic context (Room, experimental home-	style dining room, experimental	restaurant)	3 table settings: • plastic tray • home-style table • gourmet
	Nature of the product		Ready-to-eat (RTE) herb-	roasted chicken
	Selection of	participants	Participants: • Test 1: 94 • Test 2: 90 Participants were	pre-recruited
	Studied factor		Eating	locationTable	setting
	Studied	response	Food	acceptance	and intake
			García-Segovia	et al.	(2015)

c) Global and separated variable approach Study

	A. Galiñanes Plaza et al.																		Food Quality and Preference 73 (2019) 226-247
	Comments		Nature of the product differs	between contexts (entire meal	vs small bites); this	compromises the ecological	validity of lab data as small	bites cannot be compared to	regular meal consumption	situations. The nature of the	task (questionnaire filling)	differs within the field and	between the lab experiment.	There is no control over the	conditions under which foods	were tested and evaluated (by	soldiers) which may	compromise the comparison of	the data.Scope for choice may	increase ecological validity as	the task is closer to	naturalconsumption situations	The nature of the product	differs in each context as the	(continued on next page)
	Results		High correlation	between field and	laboratory scores for	snacks but not for	main dishes.	Correlations	improved when	laboratory subjects	were offered a choice	of foods											No significant	differences between
	Evaluation task		Liking ratings on a 9-point hedonic	scaleField environment: before breakfast,	soldiers chose three meals for the that	included some of the tested products and	evaluated them	Participants chose three menus in a short	period of time.Laboratory: participants	tested small bites of the stimuliChoice	simulation: participants chose three	products from a range of stimuli + tasted	and evaluated in the laboratory
	Nature of the product Experimental environment		• Main dishes (unfamiliar and 3contexts: • Field study (military camp) familiar) • 4 groupings of snacks (sweet • Laboratory • Laboratory + choice	commercial,	savory	commercial, sweet	military, savory	military), • 3 entire meal menus									Iced coffee: water and 4 contexts: • T1: Laboratory milk based
	Selection of	participants	Participants	and soldiers: • T1: 199 • T2: 36 • T3: 36 Participants	were pre-	recruited	Between-group	design											Participants: • T1: 96
	Studied Studied factor	response	Liking ratings Eating	locationChoice																			Liking and	consumption
			De Graaf et al.	(2005)
				235

Table 2

 2

	reveals that different tasks have been applied across studies:
	comparison of overall impression of served food by 9-point hedonic
	scale, comparison of overall liking by visual analogue scale (VAS),
	comparison of food attributes, comparison of consumers' willingness to
	pay, etc. (De Graaf et al., 2005; García-Segovia et al., 2015; Kozlowska

Table 2 (continued) c) Global and separated variable approach Study

 2

	A. Galiñanes Plaza et al.																	Food Quality and Preference 73 (2019) 226-247
	Comments		preparation method differs.	The experimental environment	in the T2 may has not been	perceived as representative of	real life because of external	elements that were	incongruent (ex: curtains,	candles, etc…).	Differences regarding the room	temperature in the different	studies (22 °C vs 28 °C) may	have also impacted the	evaluation of the iced coffee (a	product typically consumed in	summer)	The evaluation task also differs	among contexts: sequential	presentation versus	simultaneous
	Results		T1 and T2	Significant product	differences in T3	Differences between	laboratory and natural	settings
	Evaluation task		• Overall liking and ranging on a 21-point scale + short questionnaire	(demographic + consumption habits)
	Nature of the product Experimental environment		• T2: Laboratory + contextual	elements (curtains, pictures,	etc.) • T3: meeting room • T4: cafeteria
	Selection of	participants	• T2: 96 • T3: 52 • T4: 55 Participants	were recruited	for the	laboratory	study	Between-group	design
	Studied factor		Product	preparation	Eating location
	Studied	response
			Petit and	Sieffermann	(2007)
																					236

participants consumed less food in grams and less energy from low energy dense foods at the buffet, but

	Study Studied response Studied factor Selection of Nature of the Experimental environment Evaluation task Results Comments Study Studied response Studied factor Selection of Nature of the Experimental environment Evaluation task Results Comments Study Studied Studied Selection of Nature of the Experimental environment Evaluation task Results Study Studied response Studied Selection of Nature of the Experimental environment Evaluation task Results Comments Comments	participants product participants product response factor participants product factor participants product	Giacalone et al. Situational Familiarity Participants: • Study 1: 76 (2015) appropriateness degree Eating location • Study 2: 97 • Study 3: 93 • Study 4: 145 9 images of commercially available beers: different familiarity degree Laboratory + verbal or pictorial contexts (sports, home, alone, etc.) Participants rated all the usages they perceived appropriate for beer consumption through a checklist task Context affected differently familiar and unfamiliar products The use of pictorial contexts may help consumers to better project themselves in a particular context of consumption Kim, Lee, and Kim (2016) Food acceptability Eating location 200 participants: regular consumers of the tested product 2 types of coffee 4 contexts: • T1: Laboratory • T2: Laboratory + evocation • T3: Laboratory + physical elements • T4: Laboratory + physical Participants Participants elements + evocation • T1: overall liking on a 9-point hedonic scale. • T2, T3, T4: vividness of evocation on 9-point category scale + liking scores on a 9-point hedonic scale + involvement Vividness of evocation lasted longer in the simulated café setting, implying physical cues reinforcing cognitive evocationNo significant effect of evocation and context but evocation*context*product The experimental environment as well as the task may have not been representative for the consumers. The evaluation task may differ from one Bangcuyo et al. (2015) Liking and preference Drinking location 46 participants: regular coffee consumers Participants were pre-recruited and remunerated Within-subject 5 coffees 2 contexts: • Laboratory • Immersive café • Laboratory: demographic questionnaire + acceptability on a 9-point hedonic scale + ranking + Engagement Questionnaire • Café: same evaluation task after a month Significant differences in preference order and liking were found between contexts Participants were more discriminants in the immersive coffee and results more reliable predictor of future coffee liking van Herpen, van den Broek, van Trijp, and Yu (2016) Shopping behavior Location 100 participants: regular consumers of the tested products and buyers of the tested real supermarket Participants were Milk, fruit and vegetables and biscuits 3 contexts: • Real supermarket • 3D VR supermarket • Laboratory + supermarket pictures Same task in the 3 contexts: • buy a list of products fill a questionnaire Similar results were obtained in the VR condition and the real context for milk and biscuits. However, participants bought more products and spent more The nature of the immersive context may be representative for a coffee drinking situation Contrary to the evaluation task that may have not be representative of a natural The nature of the environment and evaluation task in the picture condition and VR may not be representative of the actual behavior. We should consider the effect of the VR devices	were pre-were pre-questionnaire participant to another: design (replication) pre-recruited money (for biscuits and fruit situation (5 testing coffees). on the evaluation task	recruited and recruited time needed to project Immersive coffee increased Between-group & vegetables), in VR and However, results from	remunerated Between-group themselves, the accuracy engagement design picture condition replication seems to confirm	total energy intakes comparison with natural Hersleth, validity of the experiment.No Monteleone, were not different between contextScope for choice increase Segtnan, and conditions ecological validity of both studies Naes (2015) Intrinsic and extrinsic product cues Eating location 120 participants: regular consumers of 6 types of dry-cured ham 2 contexts: • Evoked traditional meal • Evoked novel meal Evaluation of intrinsic characteristics on a 9-point hedonic scale. + extrinsic characteristics on a 9-point Evoked meal contexts affected both the intrinsic and the extrinsic ratings, with the strongest effect for the extrinsic The use of pictorial contexts may help consumers to better project themselves in a relation between the experiments to ensure the ecological design Combination of laboratory and field Within-group design of the scenario, etc. There is no a clear causal adding contextual elements on the simulated coffee context • Overall liking on a 9-point b) Evoked contexts the tested product scale + question about most common eating situation ratings. Consumers were somewhat more particular context of consumption Jaeger, Fiszman, et al. (2017) Hedonic product discrimination and Eating location Cross cultural study: 1727 Food and drinks familiar for the 2 contexts: • T1: Laboratory Participants discriminating when evoking a Role of product/recipe sensory participants studied population • T2: Evoked drinking a Study Studied response Studied factor Selection of Nature of the Experimental environment Evaluation task Results Comments were pre-traditional meal than a novel meal familiarity and characterization Participants particular product • T3: Evoked breakfast on a participants product • T1: overall liking on a 9-point Hein, Hamid, Jaeger, and Hedonic ratings Eating location Participants: regular apple 4 apple juices: different 2 contexts: • T1: laboratory Delahunty Product juice consumers • Test 1: 72 (2010) • Test 2: 70 Participants concentrations of citric acid and strawberry flavor • T2: evoked refreshing drink occasion hedonic scale + 2 questions about task difficulty and accuracy on a 9-point scale + open ended question about purpose of the study • Evoked context: Participants were pre-recruited and described their own Differences in hedonic ratings of the samples were observed between the two contexts. Tendency of greater discrimination in evoked context. Task was considered easier in evoked context and provided information more accurate The experimental environment might be different for each participant making difficult context comparison. The evaluation task may differ from one recruited Within-group design expectations is highlighted in this study as a key element when studying consumers' evaluation in food contexts Lusk, Hamid, Delahunty, and Jaeger (2015) Hedonic responses Eating location Evaluation task Participants: regular consumers of the tested 4 apple juices: • 2 common • 2 premium) Evoked refreshing drink occasion • S1: Overall liking on a best-worst scaling + questions about task complexity and response accuracy • S2: 9-point hedonic remunerated Between-group context + same questionnaires as T1 + 2 participant to another: time needed to project product: • Study 1: 65 design more questions about themselves, the accuracy • Study 2: 48 projection task of the scenario, etc. Participants scale + questions about task complexity and response accuracy Higher product discrimination was obtained with Best-worst scaling. Best-worst scaling was perceived as more difficult than the 9-pt scale. No difference between the two methods on the perceived accuracy of the given information The evaluation task differs between studies: S1 participants taste 3 times same products during which may lead to better product discrimination were pre-recruited Between-subject design weekend morning hedonic scale + CATA questions + questions about task difficulty and engagement No consistent trend in the results regarding the influence of evoked contexts The evoked context did not Higher product discrimination on controlled conditions c) Immersive contexts Study Studied response Studied factor Selection of participants Nature of the product Experimental environment Evaluation task Results Sester et al. (2013) Hein, Hamid, Hedonic ratings Eating Participants: Appel and 4 contexts: • T1: laboratory Jaeger, and Delahunty location Product regular consumers of blackcurrant juice: different • T2: evoked refreshing drink (2012) the tested concentrations of occasion • T3: evoked breakfast product • Test 1: 64 • Test 2: 62 • Test 3: 63 • Test 4: 68 Participants citric acid and strawberry flavor/ sucrose and orange flavor situation • T4: evoked movie situation Similar task to the previous study. • T1: after evaluate apple juices participants evaluate the blackcurrant ones • T2, T3, T4: one more question about context appropriateness Higher effect of evoked consumption contexts on hedonic response was observed for the blackcurrant juice compared to the apple juice. Lower hedonic ratings for blackcurrant juice on evoked than laboratory context The blackcurrant juice may not be representative for the evoked contextsThe experimental environment might be different for each participant making difficult context comparisonThe were pre-recruited and remunerated Between-group design de Andrade et al. (2016) Purchase intention Eating location Product presentation Participants: regular lamb consumers: • Study 1: 157 • Study 2: were pre-recruited evaluation task may differ from one 171 Lamb meat 2 contexts: • A celebratory lunch with family over the weekend (weekend lunch context) • A dinner at home after a day's work (weekday dinner context) Purchase intention on a 9-point structured scale (rating based-conjoint analysis) Purchase intention scores were significantly affected by the evoked context. Consumers were more willing to purchase lamb meat when the celebratory weekend lunch context was considered. In both contexts, price was the most The use of pictures may help consumers to better project themselves in a particular context of purchase occasion however The evaluation task may differ from one Drink choice Drinking location Participants: • Study 1A: 93 • Study 1B: 83 • Study 2A: 60 • Study 2B: 60 Participants were pre-recruited for the study 2 Within-and between-group design Drinks 4 Contexts • S1,2A: immersive bar with warmth furniture • S1,2B: immersive bar with cold furniture S1A, B: + 5 different clips S1A, B: immersive contexts influenced drink choice (association between drinks and video clips). S2A, B: drink choices were different according to the ambience Hathaway and Simons (2017) Data quality and panelist engagement Eating location 59 participants: regular consumers of the tested products Participants were pre-recruited and remunerated Within-subject design 4 commercially available chocolate chip cookies 4 contexts: • Laboratory • Mixed immersive domestic kitchen • Full immersion domestic kitchen Demographic questionnaire + acceptability on a 9-point hedonic scale + Engagement questionnaire Participants were more discriminants in the full immersion context.Similar levels of engagement in the two immersive conditionsDifferent results as regards the first and second replication with no liking differences among contexts Holthuysen et al. (2017) Overall-liking and just-about-ratings Eating location Product Participants: • Study 1, 2: 242 • Study 3: 222 Participants were recruited for the controlled and recreated condition Between-group design 2 airplane meals: 2 variants of each 3 contexts: • S1: Laboratory • S2: Recreated airplane • S3: Real airplane • S1: selection of the product + overall liking on a Visual Analogue Scale. • S2, S3: evaluation of the previous tested sample but as a full meal + overall liking on a VAS + sensory attribute rating on a JAR scale Recreated and actual airplane were more discriminant than the controlled condition. No significant difference on ratings between recreated and natural context were found Liu, Hooker, Parasidis, and Simons (2017) Food quality, nutritional content, liking Labelling 120 participants: regular peanut butter consumers divided in 3 labelling conditions Participants were pre-recruited and remunerated Between-group design Peanut butter Immersive context: virtual grocery store + 3 conditions: • Blind • Labelled • Labelled + verbal call-out Acceptability on a 9-point hedonic scale + WTP + Food quality questionnaire + demographic information Labelling improved product quality and nutritional content perception but not liking and WTP. Verbal call out improved food quality, nutritional content and WTP Sinesio et al. (2018) Food perception and liking Eating location 48 participants: regular consumers of the tested product Participants were Ouellet, Boller, Corriveau-Lecavalier, Cloutier, and Belleville (2018) Feasibility and construct validity of a new methodology Schnack, Wright, and Holdershaw (2018) Telepresence and usability Siegrist et al. (2018) Food selection Andersen et al. (2018) Desires and liking Location Memory Location Task Location Salad tomato and wild rocket salad time 60 participants Participants were pre-recruited Between and within-group design Participants: • Study 1 :49 • Study 2:35 Participants were pre-recruited Between and within-group design Participants: • Study 1: 62 • Study 2: 49 Participants were recruited Between-group design Participants: • Study 1A: 37 • Study 1B: 31 Between-group participant to another: Participants important variable participant to another: pre-recruited • Study 2: 50 design time needed to project were pre-time needed to project Within-subject Participants were pre-recruited and themselves, the accuracy recruited themselves, the accuracy design remunerated of the scenario, etc. Between-group of the scenario, etc. Between and within-design group design at different storage 2 contexts: • Study 1: Laboratory • Study 2: Immersive holiday farm dining room • S1: overall liking on a 9-point hedonic scale + perceived freshness on a 9-point scale. • S2: same evaluation task + Engagement Beverages and skin care lotion odor 3 contexts: • Laboratory • 3D VR beach • Laboratory + beach picture List of products Virtual supermarket Cereals Food products 2 contexts: • S1: 3D VR supermarket • S2: Laboratory + screen with supermarket images 2 contexts: 3D VR supermarket • S2: 3D VR supermarket • S1A: Real life supermarket S1B: Questionnaire Liking scores were higher in the immersive environment setting than in the lab. However, higher discrimination as regards storage time was found in the lab Thirst, hunger and emptiness/fullness on VAS + familiarity with VR + desires for particular beverages on a 10-point scale + odor skin liking on a 10-point scale + engagement on a 7-point Likert scale + level of excitement + choice of a snack at the end of the test Desire for cold vs hot beverages was significantly higher in the beach exposures and particularly for VR. After exposure, beach and laboratory contexts did not differ in beverages desires. Beach scenarios did not affect odor liking and no retention effect on choice behavior was observed Beach scenarios increased participant' engagement especially VR • S1: memorize a list of products + buy those products • Study 2: Multifactorial Memory Questionnaire (MMQ) + same task S1 The virtual store showed to have an appropriate level of difficulty, supporting the feasibility and construct validity of the task according to everyday memory tasks' results Same task in both contexts: products purchasing + Presence Questionnaire (7-point Likert scale) + usability and open ended questions Immersive Virtual Reality improves participants' telepresence and usability. A significant age group and gaming experience was shown package for kid's camp + one for a specific type of diet S2: select a healthy or tasty cereal package depending on the test condition (healthy or tasty) S1A, B: similar task. Select one cereal S1A, B: no significant differences between contexts were found. S2: significant differences between tasks were found. Participants spend more time for the healthy package selection than the tasty one systematically influence the results The experimental environment as well as the task may have not been representative for the consumers. The evaluation task may differ from one participant to another: time needed to project themselves, the accuracy of the scenario, etc. Comments The nature of the task in the S2 is not representative of the natural environment (triangle test) Results should be replicate in another immersive or natural environments Task in S1 is different to the S2 so the robustness of the data should be questioned (continued on next page) products liking The nature of the product, a familiar product that may be eaten in different type of contexts may have caused this effect on liking; certain product categories are more context-dependent than others First study that compares new approaches to natural conditions The nature of the task at the lab could increase consumers' attention leading to a higher discrimination (continued on next page) The nature of the stimuli, VR environment and task may have been representative of natural environments. However, a natural context comparison would be needed to prove the predictability and ecological validity of the applied methodology as electronic devices could impact consumers' evaluation ("wow" effect) The nature of the task (memorize) may have been representative of natural context. However a natural context comparison would be needed to prove those results The nature of the task (purchase) may have been representative of natural context. However, a natural context comparison would be needed to prove those results as electronic devices could impact consumers' evaluation ("wow" effect) The use of Eye tracking devices in the real life context may have reduce the ecological validity of the experiment providing similar results between S1A and S1B	(continued on next page)

(continued on next page)

A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019)

226-247 237 Table 3 (continued) b) Evoked contexts (continued on next page) A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 238 Table 3 (continued) b) Evoked contexts • S1A, B: look at the clips + order a drink from a list + bar warmth rating on a 10point scale • Study 2A, B: triangle test + questionnaire (warmth scale and bar appropriateness) A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 239 Table 3 (continued) c) Immersive contexts A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 240 Table 3 (continued) d) Virtual reality A. Galiñanes Plaza et al. Food Quality and Preference 73 (2019) 226-247 241 et al.

Table 3

 3 (continued)

	A. Galiñanes Plaza et al.
		Comments		The nature of the	environment in the	laboratory may not have been	representative of the natural	consumption setting even as a	fake buffet.	As regards the task (serving)	this may be representative for	the participants. However, a	natural context comparison	would be needed to prove	those results
		Results		No significant differences	as regards the energy	content between settings	were found
		Evaluation task		Same task in both contexts: serve	themselves a meal similar to what	they would normally have for lunch
		Experimental environment		2 contexts: • Laboratory buffet • 3D VR buffet
		Nature of the	product	3 types of	foods (Fake	food buffet)
		Selection of	participants	34 participants	Participants were	pre-recruited and	remunerated	Within-subject	design
		Studied	factor	Location
		Studied response		Energy content
	d) Virtual reality	Study		Ung, Menozzi,	Hartmann, and	Siegrist (2018)

  Chapter 5 and 6: Consumer experience of food products cannot be disentangled from the context of consumption. Likewise, the context of consumption cannot be disentangled from expectations and beliefs towards the product experience. However, in the industry, food products are usually evaluated in controlled conditions where those consumer-related variables are considered as non-existent or neutralized. Additionally, in those controlled conditions consumers' beliefs and expectations may not be expressed in the same way as in more natural contexts of consumption.This raises questions about the transferability and ecological validity of results from consumers' tests in controlled conditions to natural consumption contexts. The literature review presented in chapter 2(Galiñanes Plaza et al., 2019) showed that new methodological approaches have been developed in order to gain in ecological validity. However, apart from very few examples (Holthuysen, Vrijhof, de Wijk, & Kremer, 2017) these approaches have not been compared with truly natural consumption

contexts. This lack of comparison, could be related to the methodological aspects that entails the setting up of an experiment in natural contexts. However, the lack of data about consumer hedonic evaluation in natural consumption contexts makes it difficult to understand what contextual variables should be considered in order to improve tests conducted in controlled conditions. Hence, the first objective of this thesis is to explore what are the advantages and limitations of studying consumer hedonic responses in natural consumption contexts. For this purpose, two exploratory studies were

  Imagine you are having lunch at a fast-food restaurant like Square Flaveur. This

	Lebanese tabbouleh is offered in the menu of the day, accompanied by a sandwich
	and a dessert. »
	b. « Imagine you are having lunch at a fast-food restaurant like Square Flaveur. This
	Lebanese tabbouleh proposed by our gourmet caterer is offered in the menu of the
	day, accompanied by a sandwich and a dessert. » in the informed condition.

Table 1 .

 1 Characteristics of consumers: means (SD) or %.

	Consumers	Lyon			Paris
	Population	Non students	Students	Non students	Students
	Number of groups sessions	G1, G2, G3	G4, G5, G6	G7, G8, G9	G10, G11, G12
	Sample size (n)	16	17	25	28
	Female	81.2%	76.5%	52%	50%
	Male	18.7%	23.5%	48%	50%
	Age (year)	51.1 (9.78)	21.7 (2.29)	46.9 (8.96)	21.5 (2.19)
	Dinning out frequency
	>5 times a month	6.2%	0%	28%	42.8%
	Between 3-4 times a month	25%	47.0%	24%	42.8%

Table 2 .

 2 Pictures' sorting criteria.

	Criteria	Number of subgroups (SG)
	Physical context	14
	Decoration	5
	Ambiance	4
	Desire to go or not	3
	Price	2
	Conviviality	1
	Like or dislike	1
	Time management	1
	Time management and price	1
	Industrial food versus traditional food	1

Table 3 .

 3 Consumers' positive (+) and negative (-) attitudes towards different food consumption contexts Criteria

	Food consumption contexts

better taste and healthy: highlighted

  by all groups, especially those from Lyon and the group of non-students underlined the importance of this type of products and preparations independently of the context of consumption.

	-)/ (+) heterogeneous responses: (+) high quality: highlighted by No comments	consumers from all groups discussed all groups. The quality is high by about it	that quality is not always related to using the price as a predictor of	price when it comes to this type of the expected quality	contexts. Specially the groups from  "I Paris. will trust more a gastronomic restaurant so I	(-) price of products represent for a could take a steak tartare for	restaurant: the first time I go because I	 "For the cafeteria it's almost too estimate the price of the restaurant is related to the expensive buy at METRO. It's for quality" (woman, G4) everyday restaurants, not	gastronomic ones because they do	not buy there, but the rest." (woman	G1)	(+)  "When a cake is prepared from good and seasonal ingredients it tastes better! Because a strawberry salad in the month of December ... cherries in the month of	January ... it bothers me somehow" (woman, G4)	ingredients, no chemicals or industrial components, it concerns especially  "For me homemade is important, it means that a product has been made from natural	the pastry" (woman G1)	(-) consumers' trust:
												Homemade	products &	processes		Industrial	products &	processes

Table 5 .

 5 Consumers affective experiences depending on different food consumption contexts CriteriaAll groups discussed about what different terms such as homemade, industrial and quality means. For

	Food consumption contexts

  2 = 50.26) refers to the ambiance.

	PART C. Consumer-related variables							25.4%			18.3%			15.1%		22.6%		18.6%
																														Figure 1. Correspondence analysis and a top-down hierarchical cluster analysis of the corpus.
	363	364	365	366	367	368	369	370	371	372	373	374	375	376	377	378	379	380	381	382	383	384	385	386	387	388	389	390	391	392

Table 6 .

 6 Summary of the global analyses performed by iRaMuTeQ.

			Clusters	Significance presences of words (X 2 )	Variables (X 2 )
				Go (132.89), eat (103.3), envy (80.43),
	analysed) Cluster organisation (95.95% segments	experience (56.1%) Consumption context & eating Food ingredients & preparation (43.7%)	Eating experience (37.7%) Cluster 5: Consumption contexts Cluster 3: Affective experience (22.6%) Cluster 2: Food quality & price (15.1%) (18.4%) Cluster 1: Food process & preparation (25.4%) Cluster 4: (18.3%) Food ingredients & origin	boyfriend (55.88), context (51.84), appreciate (42.22), spend (41.19), moment (40.53), practical (36.35), institute (35), friend (34.45), mc_donald (34.17), restaurant( 32.45), habit (32.11), Bocuse (30.31) Price (361.03), pay (315.74), euro (239.44), expensive (202.88), quality (98.26), gastronomical (79.12), cost (55.45), bet (44.11), increase (39.38), expect (30.8), menu (30.63), company (30.21), associate (29.99), think (29.84) Food_truck (226,27), fast_food (138.92), classify (90.03), picture (76.04), consumer_test (68.99), rather (67.77), bistro (63.22), restoration (62.93), food (62.68), friendly (59.15), fast (58.69), table (53.24), traditional (52.31) ambiance (52.18), warmth (50.26), group (48.41), type (47.39), French (45.58), context (44.3), bouchon (41.94), place (40.22), classification (38.44), laboratory (38.2), nap (38.2), space (35.16), mass (35.16), junk_food (34.92), Asiatic (33.88), category (33.88), associate (33.88), test (31.44), brasserie (31.27), sit (30.75), together (29.9), put (27.86) Homemade (149.3), industrial (141.05), product (79.61), produce (77.53), taste (74.02), frozen (72.45), ingredient (52.93), apple (50.27), pie (49.33), home (48.98), Picard (42.93), fresh (41.06), difference (38.99), cake (38.37), preservative (36.75), dough (36.46), chocolate (32.77), transform (31.72), chemical (30.87) Meat (203.18), market (86.4), sauce (81.82), prepare (73.59), vegetable (63.45), bag (58.47), fruit (58.44), water (49.66), butcher (49.43), buy (47.5), tomato (38.04), big (38.01), chef (34.6), assembly (34.29), come (33.15), foie origin (42.79), cook (40.21), fish (38.95),	G4_Lyon_Student (24.56), G1_Lyon (2.18) G10_Paris_Student (23.21), G5_Lyon_Student (12.46), G12_Paris_Student (5.53) G8_Paris (21.07), G9_Paris (10.02), G6_Lyon_Student (5.89), G12_Paris_Student(4.68), G4_Lyon_Student (2.44) G2_Lyon (32.71), G3_Lyon (3.81), G1_Lyon (2.68), G2_Lyon (6.09)
				(31.4), chance (30.65), cut (30.11), beef
				(29.88), quantity (28.86)
	G: refers to group; Numbers (1, 2, 3, etc.): refers to the group session

Table 2 .

 2 Experimental design.

Table 1 .

 1 Characteristics of the participants in both studies: means (SD) or %.According to its label, the readymade product was composed of: cooked ham 21% (pork ham 19%, water, salt, flavorings, glucose syrup, antioxidant: sodium erythorbate, preservative: sodium nitrate), eggs 16.5%, wheat flour, canola oil, emmental cheese, green olives 7.9% (green olives 7.5%, water, salt, acidifier: citric acid, antioxidant: ascorbic acid, preservative: potassium sorbate), bamboo shoots, sugar, baking powder: Disodium diphosphate and sodium hydrogen carbonate, nutmeg, pepper.

	Contexts

Table 2 .

 2 Summary of the effects of experimental factors on liking scores. Output from the final ANOVA model (calculated with type III sums of squares).

	Source

Table 3 .

 3 Summary of the effects of experimental factors on expectations scores. Output from the final ANOVA model (calculated with type III sums of squares).

	Source

Table 1 .

 1 Characteristics of the participants in both studies: means (SD) or %.

	Restaurant

Table 2 .

 2 Online survey questions.

	197
	Questions
	Q1. Have you ever participated in a study at the "Living Lab" restaurant?
	Yes
	No
	Expectations questions
	Q2. What kind of cuisine do you expect to find at the "Living Lab" restaurant?
	Gourmet cuisine
	Traditional cuisine
	Food chain cuisine
	Collective catering cuisine
	I do not know
	Q3. What kind of dishes do you expect to find at the "Living Lab" restaurant?
	Homemade dishes cooked on site
	Already prepared dishes and just reheated on site
	Semi prepared and finalized dishes on site
	I do not know
	Q4. According to you, with what types of products will be prepared the dishes that you will find at the "Living
	Lab" restaurant?
	Mostly products purchased from local producers
	Mostly products purchased from supermarkets
	Mostly products purchased from specialized platforms
	I do not know
	Q5. What kind of plate presentation do you expect to find at the "Living Lab" restaurant?
	(on a 5 point-scale from 1 = "very elaborated" to 5 = "not elaborated at all" (mean))
	Q6. Do you expect to live an experience:
	Mostly friendly to have a good time
	Before anything else, with surprising dishes
	Before anything else greedy, with good dishes
	Above all, cheap, with a good price / quality ratio
	Q7. You will be especially deceived if
	You eat dishes that you could have found in another restaurant
	You eat dishes with frozen products
	The ingredients used are not first quality
	The price / quality ratio is bad
	The atmosphere is not friendly
	It's not good
	Opinion and beliefs questions
	(on a 5-point scale ranging from 1 = "totally agree" to 5 = "totally disagree" (mean))
	Q1. Homemade products include local and seasonal ingredients

Table 1 .

 1 Advantages (green) and limitations (red) of studying hedonic responses in natural conditions compare to CLT and evoked contexts in this thesis.

	General discussion

6. Please indicate the dishes you chose, and rate how much you liked it:

	I chose this	I like it
	(check box)	Not at all □□□□□□□□□ A lot
	Morning Offer
	Smoked trout, avocado, sour dough, spring onion and lime dressing	Not at all □□□□□□□□□ A lot
	Dipped Egg toast, plums, yoghurt	Not at all □□□□□□□□□ A lot
	Poached egg, spinach, muffin, hollandaise	Not at all □□□□□□□□□ A lot
	Lunch
	Proteins
	Spicy chicken breast	Not at all □□□□□□□□□ A lot
	Asian style roasted salmon	Not at all □□□□□□□□□ A lot
	Mediterranean tart	Not at all □□□□□□□□□ A lot
	Salad bar
	Butternut, lentils, radicchio, spinach	Not at all □□□□□□□□□ A lot
	Cracked wheat, roasted vegetables, cherry tomatoes, herbs	Not at all □□□□□□□□□ A lot
	Broccoli, peppers, chilli and garlic	Not at all □□□□□□□□□ A lot
	Potato, spring onion, truffle	Not at all □□□□□□□□□ A lot
	Mixed leaf and vegetable salad	Not at all □□□□□□□□□ A lot
	Afternoon
	Salt beef bagel, mustard mayonnaise, lettuce, pickles and tomato	Not at all □□□□□□□□□ A lot
	"Cheese on toast", lettuce, tomato, sour dough	Not at all □□□□□□□□□ A lot
	7.

According to you, has this meal met your expectations?

	Far below				Met				Well above
	my expectations				my expectations				my expectations
	□	□	□	□	□	□	□	□	□
	8

. How much did you like this meal, overall?

	Not at all □ □ □ □ □ □ □ □ □ A lot
	9. How hungry are you?
	I am not hungry at all □ □ □ □ □ □ □ □ □ I am very hungry
	10. Do

you have any additional comments about your meal, or the experiment?

	Once
	_____________________________________________________________________________________________
	_____________________________________________________________________________________________
	_____________________________________________________________________________________________

you have eaten Thank you for your participation! 6. Please indicate the dishes you chose, and rate how much you liked it: I chose this (check box) I like it Not at all □□□□□□□□□ A lot Morning Offer Hot smoked

  trout, smashed avocado, sour dough toast, spring onion and lime dressing Not at all □□□□□□□□□ A lot French toast, spiced plums, honey Greek yoghurt Not at all □□□□□□□□□ A lot Poached egg Florentine -baby leaf spinach, egg, toasted English muffins, hollandaise Not at all □□□□□□□□□ A lot Lunch Proteins Harissa and coriander yoghurt grilled chicken breast Not at all □□□□□□□□□ A lot Ginger, soya and honey roasted salmon Not at all □□□□□□□□□ A lot Wilted Spinach, sundried tomato and goat's cheese tart Not at all □□□□□□□□□ A lot Salad bar Roasted butternut, lentils, radicchio and baby leaf spinach Not at all □□□□□□□□□ A lot Cracked wheat, roasted vegetables, cherry tomatoes, micro herbs Not at all □□□□□□□□□ A lot Roasted broccoli, fire roasted peppers, chilli and garlic Not at all □□□□□□□□□ A lot Boiled new potato, spring onion and truffle mayonnaise Not at all □□□□□□□□□ A lot Mixed leaf and vegetable salad Not at all □□□□□□□□□ A lot Afternoon Salt beef bagel, American mustard mayonnaise, shredded lettuce, pickles and tomato Not at all □□□□□□□□□ A lot Blue cheese and walnut 'rarebit', shredded lettuce, tomato, sour dough Not at all □□□□□□□□□ A lot

7. According to you, has this meal met your expectations?

	Far below				Met				Well above
	my expectations				my expectations				my expectations
	□	□	□	□	□	□	□	□	□
	8.

How much did you like this meal, overall?

	Not at all □ □ □ □ □ □ □ □ □ A lot
	9. How hungry are you?
	I am not hungry at all □ □ □ □ □ □ □ □ □ I am very hungry
	10. Do

you have any additional comments about your meal, or the experiment?

	Once
	_____________________________________________________________________________________________
	_____________________________________________________________________________________________
	_____________________________________________________________________________________________

you have eaten Thank you for your participation! 6. Please indicate the dishes you chose, and rate how much you liked it: I chose this (check box) I like it Not at all □□□□□□□□□ A lot Morning Offer Hot smoked trout (Fish on the menu is from sustainable stock), smashed

  avocado, sour dough toast, spring onion and lime dressing Not at all □□□□□□□□□ A lot French toast, spiced plums, honey Greek yoghurt Not at all □□□□□□□□□ A lot Poached egg Florentine -baby leaf spinach, free

range egg (All eggs are free range), toasted

  English muffins, hollandaise Not at all □□□□□□□□□ A lot Lunch Proteins Harissa and coriander yoghurt grilled chicken breast (

All of our fresh chicken is freedom farmed and red tractor certified)

  Not at all □□□□□□□□□ A lot Ginger, soya and honey roasted salmon (MSC certified fish) Not at all □□□□□□□□□ A lot Wilted Spinach, sundried tomato and goat's cheese tart Not at all □□□□□□□□□ A lot Salad bar Roasted butternut squash, beluga lentils, radicchio and baby leaf spinach Not at all □□□□□□□□□ A lot Organic cracked wheat, roasted vegetables, cherry tomatoes, micro herbs (grown onsite) Not at all □□□□□□□□□ A lot Roasted broccoli, fire roasted peppers, chilli and garlic Not at all □□□□□□□□□ A lot Boiled new season potato, spring onion and truffle mayonnaise Not at all □□□□□□□□□ A lot Chefs mixed leaf and vegetable salad Not at all □□□□□□□□□ A lot Afternoon Salt beef (100% Fresh British Beef) bagel, American mustard mayonnaise, shredded lettuce, pickles and tomato Not at all □□□□□□□□□ A lot Cashel blue cheese and walnut 'rarebit', shredded lettuce, tomato, sour dough Not at all □□□□□□□□□ A lot

7. According to you, has this meal met your expectations?

	Far below				Met				Well above
	my expectations				my expectations				my expectations
	□	□	□	□	□	□	□	□	□
	8.

How much did you like this meal, overall?

  . Le fait qu'un produit soit apprécié lors d'un test ne garantit pas que ce produit soit acheté et consommé. Comme Meiselman l'a expliqué à propos du comportement alimentaire des consommateurs, des facteurs liés au contexte peuvent être pris en compte afin de comprendre comment et quand les produits sont consommés. Les entreprises agro-alimentaires lancent chaque jour des produits sur le marché. Cependant, dans les pays occidentaux, entre 80 et 90% des nouveaux Résumé en Français et les attentes du consommateur peuvent ne pas être exprimées de la même manière que dans des contextes de consommation plus naturels. Cela soulève des questions sur la transférabilité et la validité écologique des résultats de tests effectués par les consommateurs dans des conditions contrôlées dans des contextes de consommation naturels. La revue de la littérature que nous avons menée (Galiñanes Plaza et al., 2019) a recensé de nouvelles approches méthodologiques développées pour gagner en validité écologique. Cependant, mis à part très peu d'études (Holthuysen, Vrijhof, de Wijk et Kremer, 2017), ces approches n'ont pas été comparées à des contextes de consommation véritablement naturels. Ce manque d'éléments de comparaison pourrait être lié aux aspects méthodologiques et logistiques qui impliquent la mise en place d'une expérience dans des contextes naturels. Ainsi, le manque de recul sur l'évaluation hédonique du consommateur dans des contextes de consommation naturels rend difficile la compréhension des variables contextuelles qu'il faudrait prendre en compte pour améliorer les tests effectués dans des conditions contrôlées. Par conséquent, le premier objectif de cette thèse est d'explorer quels sont les avantages et les inconvénients d'étudier le niveau d'appréciation du consommateur dans des contextes de consommation naturels. À cette fin, deux études exploratoires ont été menées dans des contextes différents et dans des conditions différentes. Dans les deux études, nous avons testé le rôle de l'information. Des études précédentes ont montrées l'influence de l'information sur les croyances et les attentes du consommateur modifiant son évaluation hédonique et son comportement (choix) vis-à-vis des produits testés

Acknowledgements

The authors acknowledge Herb Meiselman for his kind comments and suggestions on this paper first draft. This review is part of a PhD project funded by the Société Scientifique d'Hygiène Alimentaire (SSHA).

Acknowledgements

The authors acknowledge Blandine Cerisier for her kind comments and suggestions with the qualitative and quantitative analysis. This work is part of a PhD project funded by the Société Scientifique d'Hygiène Alimentaire (SSHA)

Acknowledgements

The authors would like to thanks the CROUS of Lyon (Regional Centers of University and Academic Services) for its collaboration in providing the place and products of study. Thanks to the PhD students of the Research Center of Paul Bocuse Institute for their help in collecting questionnaires at the university cafeteria. This work is part of a PhD project funded by the Société Scientifique d'Hygiène Alimentaire (SSHA).

Acknowledgements

The authors thank all collaborators of the Institut Paul Bocuse for their assistance in this experiment. This work is part of a PhD project funded by the Société Scientifique d'Hygiène Alimentaire (SSHA).

Acknowledgements

The authors thank all collaborators of the Research Center of the Institut Paul Bocuse for their assistance in this experiment. This study is part of a PhD project funded by the Société Scientifique d'Hygiène Alimentaire (SSHA).

Date : __ / __ / __

Code consommateur : _____

Aujourd'hui votre repas au Restaurant Expérimental est l'occasion de prendre part à une étude menée par le Centre de Recherche.

PART A: Literature review and Research Hypotheses

The pursuit of ecological validity through contextual methodologies (Article 1)

PART A: Literature review and Research Hypotheses

The third and fourth principles refer to risky situations that are not central in hedonic evaluation.

Therefore, the rest of this chapter will focus mainly on the first two principles.

Framing effects and reference point

Framing effects are attributed to the fact that "alternative formulations of a same situation make different aspects of it accessible", resulting in potentially different outcomes (Kahneman, 2002, p.481). Depending on the type of information and/or the amount of information accessible when consumers make a decision, their perception of an object or situation may vary, modifying consumers' judgements.

To illustrate this, McNeill et al., (1982) presented two different choices of cancer treatment to two different groups: patients and doctors. They could choose between surgery and radiation therapy.

Surgery entailed a risk of 10% of perioperative mortality but a longer life-expectancy compared to the radiation therapy; this means a higher long-term option at the cost of a greater immediate risk. The authors described the outcomes of the decisions by survival and mortality rates. Within the groups some of the participants received the outcomes of their decisions on survival rates whereas the rest on mortality rates. They showed that as "90% short-term survival is less threatening than 10% immediate mortality, the survival frame yielded a substantially higher preference for surgery than radiation" (sample retrieved in Kahneman, 2002, p. 457).

This example highlights the importance of the task's formulation on consumers' perception. The way the attributes of an object or situation are perceived depends on the context in which the object or situation is evaluated, and on the reference used as a point of comparison with a prior or another evaluation [START_REF] Kahneman | Nobel prize lecture: Maps of bounded rationality: A perspective on intuitive judgement[END_REF].

Figure 4 shows two large squares: one black (left) and another one grey (right), each containing a smaller square. The square in the middle is identical in both cases; however, we perceive its color as brighter in the left image because it is framed within a more contrasting hue. When consumers respond to attributes such as brightness, temperature or taste, the past and present contexts of an experience define a reference point: "stimuli" are perceived in relation to this reference point [START_REF] Higgins | The Loss of Loss Aversion: Paying Attention to Reference Points[END_REF]. Reference points are considered the status quo or current state from which consumers make the evaluation of outcomes [START_REF] Tversky | Advances in Prospect Theory : Cumulative Representation of Uncertainty[END_REF]. Outcomes can be perceived differently if the reference point changes or is manipulated [START_REF] Jervis | The Implications of Prospect Theory for Human[END_REF], through aspirations, expectations, norms, and social comparisons (Tversky & Kahneman, 1991).

PART A: Literature review and Research Hypotheses modulated through consumer-related variables such as beliefs and expectations. The present chapter proposes to go a step further by focusing on the interaction between the food and the consumer in a particular context, drawing consumers' attention to specific aspects of the product-related variables intimately associated to consumers' beliefs and expectations. Because of the use of product-related information, consumers' beliefs and expectations are expected to change the reference points created from environmental and product-related variables, helping to explain contexts effects on consumer hedonic evaluation. To do so, this chapter includes two different studies:

 "Cakes" study: The purpose of this study was to investigate the extent to which different aspects of the context (eating context, product context, information context) could act as reference points in consumer hedonic evaluation. Following a between-subject design, two contexts (CLT and restaurant) and two versions of a product (ham-olives cake homemade and readymade) were tested. Consumers' hedonic responses were assessed as well as the level of fulfillment of their expectations. Additionally, two different information conditions were tested (blind and informed). The following hypotheses were formulated:

 Hypothesis 1: In the restaurant, consumers liking scores would be higher than in the central location test (standard testing room).

 Hypothesis 2: Information about homemade products would obtain higher rates than readymade products regardless of contexts.

 Hypothesis 3: The impact of information regarding food quality (homemade and readymade) would differ depending on the testing location.

 "Quiche" study: The purpose of this study was to examine the influence of the type of information provided on food preparation and origin of ingredients on consumers' hedonic responses to a product in a natural consumption context. Following a between-subject design, consumers' expectations and beliefs towards a specific context (restaurant), together with consumer hedonic responses in that specific restaurant were assessed. Additionally, two different information conditions were tested related to consumers' expectations. The following hypotheses were formulated:  Hypothesis 1: Consumers' expectations and beliefs towards food in a particular context would help to explain consumers' hedonic responses.

 Hypothesis 2: "Consistent information" with consumers' expectations and beliefs would increase participants liking scores compare to "inconsistent information".

 Hypothesis 3: Food-related factors would influence consumers' overall satisfaction.

Chapter 5. Standardisation of product-related variables in context studies

The present chapter aims to identify how environmental-related variables may influence consumer hedonic evaluation when product-related variables are standardized. Moreover, the feasibility of context studies a large scale and their potential improvements and limitations for future studies were addressed. This work is presented in the following preliminary study.

Moreover, aspects like the origin of ingredients and the traceability were also discussed by some of the groups underlining differences attitudes between local producers and food retailers.

PART C. Consumer-related variables Cluster 1 and 4 differed from clusters 3, 2 and 5 as they were associated to the food ingredients and food preparation items. The three focus groups of non-students from Lyon, G1 (X 2 = 2.68), G2 (X 2 = 32.71) and G3 (X 2 = 3.81) contributed to the creation of cluster 1, and the focus group G2 (X 2 = 6.09) contributed to the creation of cluster 4. In cluster 1 we found words associated to food processes such as "homemade" (X 2 = 149.3), "industrial" (X 2 = 141.05), "produce" (X 2 = 77.53), "taste" (X 2 = 74.02), "frozen" (X 2 = 72.45) that underline the differences consumers make when eating in different contexts, and the attitudes towards those processes as well as the knowledge consumers have about them. In the case of cluster 4, the use of nouns and verbs related to ingredients and origins characterized it. We found nouns such as "meat" (X 2 = 203.18), "sauce" (X 2 = 81.82), "vegetable" (X 2 = 63.45), "market" (X 2 = 86.4), "butcher" (X 2 = 49.43), and verbs such as "prepare" (X 2 = 73.59), buy (X 2 = 40.21), and cut (X 2 = 30.11).

PART D. EVALUATION TASK-RELATED VARIABLES

This work is presented in Article 3 (short communication), submitted to Food Quality and Preference (April 2019).

Hedonic responses sensitivity to variations in the evaluation task and culinary

preparation in a natural consumption context (Article 3) PART D. Evaluation task-related variables preparation could be done without altering its visual appearance. Moreover, the food service company running the cafeteria was also interested in their customers' opinion on pizzas.

Three versions of Margherita pizza were prepared together with the chefs: a homemade Margherita pizza, a readymade Margherita pizza and an in-between 'mixed' Margherita pizza made with a readymade dough. These three types of pizzas were served respectively on three separate days to avoid any confusion in the preparation and potential comparison bias. Table 1 shows the differences among the three versions of pizza. The evaluated samples consisted of 30g of bread (individual portion size) and 300g±5g of Margherita pizza (individual portion size). Each type of pizza was prepared and served in different days but following the same procedure. The homemade dough and tomato sauce were prepared a day before the service. From the homemade dough (four, yeast, water, salt), balls of 160g were cut to follow the same size of the readymade dough (Mademoiselle Desserts St Renan, France) and they were kept at 4°C in the fridge. For the tomato sauce, ingredients were mixed the day before (tomato, oregano, basil, pepper, olive oil) and they were also kept at storage at 4°C. The day of the study all preparations started at 6.30am. The oven was turned on at 350°C and set at speed of 2.5. Both types of dough (homemade and readymade) were kneaded by using a pizza dough "paver" and then placed on dishes

where the tomato sauce, cheese and olives were added. The readymade pizza (Marie surgelés, France) followed the same last step of the protocol where the cheese and olives were added. The pizzas were cooked in the oven and stored in a refrigerator (4 °C) until the cafeteria was opened. Once the service started (11.30am) the pizzas were re-heated in the oven at 350°C and at speed 2 on demand.

Evaluation task

Following the protocol of Prescott, Lee, & Kim, (2011), we first asked participants about their liking on a 11-point hedonic scale with end-point descriptors (0 = dislike very much -10 = like very much).

For the analytical group, we also asked to evaluate a series of attributes related to the pizza or bread on a 11-point category scale with end-point descriptors (0 = very weak -10 = very strong). The attributes asked were:

Title:

Eating location as a reference point: differences in hedonic evaluation of dishes according to consumption situation

Authors:

Galiñanes Plaza, A. a,b , Saulais, L. c,b , Blumenthal, D. a , Delarue, J.

Abstract:

Numerous studies have been conducted on the influence of physical context on consumer evaluation of food and its link with the ecological validity of sensory and consumer tests. Conversely, there has been little focus on the way context shapes attitudes and expectations towards food despite their likely influence on consumers' reference framework of evaluation. This study investigates the extent to which different aspects of the context (eating context, product context, information context) can act as reference points in consumers' judgement of food.

Following a between-subject design, we asked participants to rate their liking for two variants of a given food (ham-olives cake) as well as the level of fulfillment of their expectations in two contexts:

an experimental restaurant (N=145) and a standard testing room (N=136). Additionally, in each context, half of the participants tested the products blind while the other half was informed about the quality of the food as related to the preparation conditions (readymade or homemade).

Participants rated products higher in the restaurant setting, regardless of the product version. Besides, information played a key role on participants' evaluation of the readymade version. Fulfillment of expectations scores followed a similar pattern. Furthermore, the order in which the two versions were presented had a significant effect on liking and on the fulfillment of expectations, revealing a possible contrast or disappointment when the readymade version was presented second. Observed interindividual differences in both liking and expectations fulfillment scores suggest that the context effect on hedonic response is related to participants' prior beliefs and/or expectations.

Keywords:

context; product information; liking; expectations; evaluation framework PART E. Product-related variables Before the dinner, a waiter proposed the cakes, presented as a set of two versions of an appetizer together with a drink, and indicated that participants would have to fill out a short questionnaire during and after the tasting. First of all, the drink (iced tea or water) was served and then the questionnaire was brought together with a pen. Prior to consumption, consumers had to indicate if they had any allergy or dietary restriction.

Appetizers were presented in a monadic sequential way. Once participants had rated the first sample, the second one was presented. Once the appetizer tasting was finished the rest of the dinner took place.

B. Standard Testing Room (STR)

Testing in the standard controlled environment took place in one of the classrooms adjacent to the Research Centre of the Institut Paul Bocuse. A picture of this STR can be seen in Figure 2.B.

Participants were seated and instructions about the test were given by a researcher. The procedure was the same as in setting A, except that in this case, water was the only drink offered.

Experimental design

Information conditions

Two information conditions were tested in each setting. In the non-informed condition, consumers were provided the two versions of the product with no information about the differences between the two product versions. In the informed condition, homemade cakes were presented together with a label displaying "fait maison", whereas the readymade version was presented with a label displaying "industriel".

Sessions

The experiment followed a 2 (setting) x 2 (information condition) design. For all conditions, the two products were first evaluated and then, participants had a dinner at the "Living Lab" restaurant. The experimental campaign was conducted over the course of two weeks (one per setting), and sessions PART E. Product-related variables

Results

Liking scores

On average, the cakes were well liked by the participants in both settings (Figure 3). As expected, the homemade cake was more liked (x ̅ =7.0±1.7) than the readymade one (x ̅ =5.6±2.2) regardless of the experimental condition. The analysis of variance shows that the product version induced the most important differences in liking (Table 2). The liking scores also differed depending on the settings (scores being significantly higher in the restaurant than in the STR (p = 0.005)).

. Effects of sample presentation order

The order of sample presentation resulted in a significant difference in the overall liking scores of both product versions (F (1, 280) =7.76; p = 0.006). However, only the readymade cake was significantly affected (p < 0.001) -with liking scores dropping 1 unit (on the 11-point hedonic scale) -when tested second, after the homemade cake (Figure 5).

Fulfillment of expectations

After participants tasted each product, they were asked to rate the extent to which the product met their expectations or not. Results for the fulfillment of expectations scores showed a similar pattern as the liking scores. We observed a significant effect of product version, settings and order of sample presentation on the fulfillment of expectations scores (Table 3).

PART E. Product-related variables In order to better reflect the actual data range, the axis was anchored from -1.5 to 1.5 instead of -5 to 5.

Effects of sample presentation order

The sample presentation order also affected participants' fulfillment of expectations scores (F (1, 279) = 4.65; p = 0.032). Nevertheless, the two versions of the cakes were differently affected as Figure 7 shows. The order of sample presentation did not affect participants' scores of fulfillment of expectations for the homemade version (p=0.998). However, the scores of the readymade version were significantly lower (p < 0.001) when this version was tested second. Moreover, the three-way interaction product * information condition * presentation order was significant (F (1, 279) = 4.37; p = 0.037). It shows that the presence of information provoked even a higher deception among participants who scored this product as much lower than their expectations (Figure 8).

PART E. Product-related variables PART E. Product-related variables 3.2.3. Inter-individual differences: analysis of liking and scores of fulfillment of expectations

In Figure 9, the first thing to note is that the overall shape of the liking score distribution is different for the homemade and the readymade versions. The homemade version shows a higher consensus on the liking scores whereas the readymade version shows a bimodal distribution, especially at the STR setting in non-informed condition.

In order to explain those differences, we highlighted participants whose expectations were not met.

We indeed classified participants' responses into two groups: "satisfied" (whose expectations were met or exceed) represented in green and "deceived" (whose expectations were not met) in red. Overall, satisfied participants outnumbered deceived participants (11.6% in the STR, 4.2% in the restaurant).

However

Title:

Associations between prior expectations towards meal experience and hedonic responses in the restaurant: the role of information

Authors:

Galiñanes Plaza, A. a,b , Saulais, L. c,b , Delarue, J.

Abstract:

Consumers' meal experience changes depending on the context of consumption as consumers' expectations and beliefs towards the food served in different contexts may do. Food-related factors have drawn the attention of consumers who have become more demanding when eating out. This study examines the extent to which different factors related to food (preparation and origin) influence consumers' hedonic responses and meal satisfaction in a natural consumption context. Following a between-subject design, participants (n=114) first answered an online survey focused on consumers' expectations and beliefs towards the meal experience they expected to find in a specific local restaurant. Second, participants came to that restaurant and were asked to rate their liking of a given dish (tartlet), the perception and liking for different sensory attributes, and their overall satisfaction.

Half of the participants (n= 56) received consistent information about food-related factors that was congruent with consumers' expectations as elicited in the questionnaire prior to the test, while the other half (n = 58) received information that was inconsistent with these expectations. Consumers' prior expectations and beliefs towards the restaurant and the served food suggested to modulate consumer hedonic responses. Participants with consistent information about consumers' expectations towards food-related factors rated the tartlet higher than those who were presented with more inconsistent information. Furthermore, the presence of information influenced the ratings of sensory attributes (those related to the dough) for both intensity and liking scores. Consumers' food satisfaction and overall meal experience were significantly higher in the consistent information condition.

Keywords:

expectations; beliefs; product information; liking PART E. Product-related variables

Experimental design

Online survey

An online survey was created in order to collect consumers' prior expectations and beliefs towards the "Living Lab" restaurant and the food served in it. The survey was divided into two sections (Table 2):

(1) expectations and ( 2) participants' opinions and beliefs. Questions related to the type of cuisine, origin of ingredients and food preparation consumers' expected and thought to have were presented.

These questions were formulated based on literature review that indicates that consumers search for homemade products and local ingredients when eating out (GIRA Conseil, 2013). The objective of this step was to (i) control consumers' expectations and beliefs towards the restaurant (consumers mostly expected to find homemade products with ingredients from local suppliers"), and (ii) customize and validate the information conditions.

Information conditions

Two information conditions were tested related to consumer prior expectations and beliefs measured in the online survey: consistent information and inconsistent information. The menu of the day was presented to participants on a menu card. Some information about the dishes and ingredients was included next to the description of the dish for the appetizer. Depending on the information condition, the following information was presented: The experiment followed a 1 (setting) x 2 (information condition) design and it was conducted during one week in the month of July at midday. The two experimental conditions (consistent and inconsistent information) were conducted in separate days to avoid confusion and uncontrolled information.

Experimental procedure and evaluation task

Participants had to complete an online survey to register their booking at the restaurant one week before the booked date. Each participant was given a code during the booking process that was used for the online survey and at the restaurant.

 Online survey: Participants get an email of confirmation together with a code and a link to complete the survey. The responses obtained allowed us to validate the information conditions and relate hedonic responses in the "Living Lab" with these results through the information condition, while guaranteeing their anonymity.

 "Living Lab" restaurant: Once participants signed the consent form at their arrival to the restaurant, they were shown to their table. The table already had the code of each participant so they were asked to sit in their correspondent code. Once they at the table, the waiter arrived and gave the menu card (with either consistent or inconsistent information, depending on the condition), together with a questionnaire. The waiter asked participants to read it and to start completing the first questions of the questionnaire, related to their familiarity to the type of appetizer that would be served (6-point scale ranging from 0 = "not familiar at all" to 5 = "very familiar"), and their liking for this type of product (11-point hedonic scale, ranging from 0 = "I do not like it at all" to 10 = "I like it a lot"). After a couple of minutes, the waiter arrived with the appetizer and presented it to the participants repeating the information given in the menu (consistent or inconsistent depending on the condition). Participants were then asked to rate their liking for the presentation of the appetizer and their overall liking on a 11point hedonic scale (ranging from 0 = "I do not like it at all" to 10 = "I like it a lot"). Then, participants rated the intensity perceived of the five specific sensory attributes of the product (11-point scale ranging from 0 = "very weak" to 10 = "very strong") and their liking of such PART E. Product-related variables attributes (ranging from 0 = "I do not like it at all" to 10 = "I like it a lot"). The attributes evaluated were: tomato flavor, cheese flavor, buttery dough flavor, salty flavor, crusty dough.

Finally, questions related to participants' satisfaction were also collected on a 6-point scale (ranging from 0 = "not satisfied at all" to 5 = "very satisfied"). All responses were collected using a paper form.

Data analysis

Descriptive analyses were conducted on the online survey data (XLSTAT Addinsoft (2019). statistical and data analysis solution. Paris, France). Comparisons between proportions were performed using a z-test when differences between groups were observed.

Liking data of the product, intensity and liking data of the sensory attributes and satisfaction questions were analyzed using Student t-tests.

Results

Online survey data

85.5% of the participants had no previous experience at the "Expérience" restaurant. Nonetheless, they had expectations towards the type of cuisine and the dishes offered. Table 3 shows the results for the different questions related to participants' expectations as well as participants' opinions and beliefs.

Results are presented according to the information condition in which participants were assigned.

Differences were observed between the groups regarding the kind of dishes (Q3), with a larger proportion of consumers expecting already prepared dishes in the "inconsistent information" group. Moreover, differences were also observed regarding consumers' deception (Q7), with a larger proportion of consumers deceived if frozen products would be served in the "consistent information" group; whereas a larger proportion of consumers indicated to be deceived if the taste was not good in the "inconsistent information" group. However, no significant differences between percentages were observed between the two information conditions: Q3 (z = -0.479; p = 0.316); Q7 (i) (z = 1.519; p = 0.936) and (ii) (z = -1.629; p = 0.052). In general, both groups expected to find a gourmet cuisine (57.3%), with homemade dishes (89.7%), mostly prepared with products from local producers 64.1%

and, a very elaborated presentation (56.4%). General discussion lunch, this may have led them to simplify their food decisions by directly asking the catering service. [START_REF] Fernandes | Influence of menu labeling on food choices in real-life settings: A systematic review[END_REF] argue that differences in the type of foodservice (cafeteria, restaurant, etc.) induce different behavior so the presence of information may lower or improve consumer responses depending on the context of consumption.

From these two first studies we observed how consumers differently behaved depending on the context and how different contextual variables could be interrelated. Moreover, as the objective was to determine the advantages and limitations of a hedonic evaluation study setup in a natural condition, some insights were drawn from those experiences. Table 1 summarizes the critical points of each context by looking at each of the four categories of contextual variables. Besides, as several contexts were tested during this thesis, their advantages and limitations are also included in the table. Studying hedonic responses in natural conditions allowed us to observe the natural behavior of consumers in different consumption contexts. Moreover, when consumers actually paid for their food, food value could be also addressed as part of the consumer experience. Nevertheless, introducing a questionnaire changes these conditions, which may modulate consumers' attention and hedonic responses.

Furthermore, not all consumers appreciated having to answer a questionnaire while eating, due to time constraints in the case of the conference event and university cafeteria, what could influence as well consumer experience and in turn, hedonic responses. With regards to the product-related variables, the main limitation offered by the natural conditions was the lack of control over the preparation of the food in contexts such as the conference event and university cafeteria, where food caterers were the main stakeholders, so modifications in terms of food preparation were more difficult to conduct and to control.

General discussion

Furthermore, as it was reported in chapter 7, consumers agreed that meal experience cannot be perceived in a sensory booth as the context of consumption is missing. Although some consumers agreed that test products in a sensory booth could be an interesting experience, most of the consumers agreed that this type of experience make them feel like "if they were in an exam" or like if they were "laboratory rats". Then, we may consider that consumers' mindset when coming to a consumer test in controlled conditions may differ from consumers' mindset when going to a restaurant, what could already influence the way in which consumers are going to perceive and evaluate a product.

Additionally, from this third study we realized that consumers differently evaluate the presence of contextual variables, especially food-related variables. In most of the context studies conducted in natural conditions, it is almost impossible to disentangle the influence of different contextual variables on consumer hedonic responses. However, these variables may have higher or lower effect on consumer hedonic evaluation depending on the context and meal or product experience. For example, consumers highlighted that in workplace or school cafeterias, conviviality plays a major role on the meal experience compared to other contexts where food becomes the central part of the meal experience, such as gastronomic restaurants. This difference among contexts was associated to the food value perceived by consumers. In fact, consumers associated the quality of the served food in different contexts to the price payed for it. This is a key element that context studies rarely considered when comparing consumer hedonic evaluation in different context, although it has shown to have an impact on consumer experience and satisfaction (Ozdemir & Caliskan, 2014;Timothy, Yang, & Kim, 2016).

Concerning food value and the perceived quality of food products, chapter 7 showed that consumers associated the perceived quality of food to different consumption contexts. These results are not new as previous studies have shown the negative image about food, consumers have in contexts such as institutional restaurants or hospitals (Cardello, Bell, & Kramer, 1996;[START_REF] Edwards | The relationship between emotions, food consumption and meal acceptability when eating out of the home[END_REF]. However, we found that the quality of products was associated to the origin of ingredients and preparation method, especially to the use of readymade and homemade products. This could be related to the category of products consumers taste: standardized product or a product (dish) that requires a preparation. The literature review (chapter 1) showed that food preparation has not been widely explored when comparing context studies. However, a dish prepared in the laboratory may taste different from another one prepared in another context, due to the effect of the preparation in the sensory properties of a product and to the consumers' expectations and beliefs towards those contexts.

Related to this issue, we observed that consumers have different levels of expectations and beliefs depending on the context of consumption and the quality of the served food. In workplace and school cafeterias, together with fast food chains and certain bistros or brasseries consumers expected to find General discussion the expectations. The results showed that the context of the evaluation task had an effect stronger than the actual context of consumption (CLT and restaurant). In the case of natural consumption contexts such as restaurants, a monadic sequential presentation of the products may decrease the ecological validity of the results. Nevertheless, depending on the type of product tested -standardized (snacks) or a product that requires a preparationthe type of methodology applied may have higher or lower effects.

The fifth study (chapter 9.2) did not assessed consumers' expectations and beliefs. However, in the last study (sixth study, chapter 9.3), we controlled those variables. Consumers showed to have specific expectations and beliefs towards the restaurant food offer: homemade dishes made with local ingredients. From those results information conditions were set and used to see the influence of information on consumer hedonic evaluation. In this study we investigated if variations in the type of information modulate consumers' reference points in a particular context. Consumers with consistent information about expectations towards food-related factors, rated the product higher than those who were presented with more inconsistent information. Moreover, consumers scored higher their satisfaction when the information was consistent with their expectations and beliefs. We should underline that in this last study consumers also paid for their menu what may include the food value variable in the evaluation. Bringing back Prospect theory, the second principle of this theory posits that it is harder to lose than it is good to gain [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF]. All consumers expected to find a certain quality related to homemade dishes from local ingredients. However, those who received the inconsistent information may perceive a lost compare to those who received the consistent information even if the product was exactly the same. This raises several question: is liking a good indicator when comparing context studies? and what is the minimum level of food acceptability (liking) at different context of consumption? As in controlled conditions, consumer hedonic evaluation rarely included the food value variable, studies in natural consumption contexts with similar environmental-related variables could help to answers those questions.

New questions raised by our experimental studies: Perspectives

The present work has arisen new questions regarding the effects of context on consumer hedonic evaluation.

Product categories: Standardized products versus products that require preparation

We have observed that certain products may be able to pass across contexts whereas others may not, as it could be the case of food dishes or products that require a certain level of preparation. Familiarity

Après la dégustation du taboulé Libanais Pour terminer, quelques questions sur vous

Veillez à répondre à toutes les questions.

Avant la dégustation du taboulé Libanais

Appendix 2: Food Matters Live questionnaires (Experiment 2)

Date :

ID Code :

The Centre for Food and Hospitality Research of the Institute Paul Bocuse is pleased to welcome you to this unique live experiment, in which we will observe how food choices available at these events influence your decision.

All you need to do is complete this questionnaire about your meal.

The information collected is completely anonymous. The data will be used exclusively for research purposes, and confidentiality is guaranteed. The Centre for Food and Hospitality Research of the Institute Paul Bocuse is pleased to welcome you to this unique live experiment, in which we will observe how food choices available at these events influence your decision.

Enjoy

All you need to do is complete this questionnaire about your meal.

The information collected is completely anonymous. The data will be used exclusively for research purposes, and confidentiality is guaranteed. The Centre for Food and Hospitality Research of the Institute Paul Bocuse is pleased to welcome you to this unique live experiment, in which we will observe how food choices available at these events influence your decision.

Enjoy your meal, and thank you for your

All you need to do is complete this questionnaire about your meal.

The information collected is completely anonymous. The data will be used exclusively for research purposes, and confidentiality is guaranteed. -Présentation Vous êtes aujourd'hui réunis afin que vous puissiez discuter ensemble, en petit groupe, de quelque chose que vous rencontrez tous au quotidien : manger. Ce travail s'inscrit plus largement dans le cadre d'une thèse que je réalise actuellement au sein de AgroParisTech et le centre de recherche de l'Institut Paul Bocuse -Concernant le déroulement de cette discussion :

Enjoy your meal, and thank you for your

Les échanges dureront 1h30. Il sera principalement question de vos façons de voir la nourriture dans différents contextes de consommation, ce qu'elle évoque pour vous et les réactions qu'elle peut impliquer chez vous. Ce sont donc vos avis qui m'intéressent. Vous n'avez pas été réunis pour l'expertise que vous avez ou non dans ce domaine mais plus pour les expériences quotidiennes que vous vivez dans différents lieux. Chacun est libre de prendre la parole et mon rôle sera justement de m'assurer que chacun puisse s'exprimer librement. Je vais vous proposer de commencer pour l'évaluation de ces photos. Cela facilitera la discussion. Puis dans une seconde partie, on discutera de différents aspects et on finira pour remplir un questionnaire. Il s'agit davantage d'une discussion entre vous. Je suis simplement là pour animer cette rencontre.

-Enregistrement et anonymat :

Cet échange anonyme est enregistré et filmé afin de me permettre de le revoir, de le réécouter, et de l'analyser plus tard. En aucun cas je ne divulguerai les noms des participants à cette discussion. Ceci permet une plus grande liberté de parole pour les participants. De plus, comme je vais rencontrer d'autres groupes, il est préférable pour le bon déroulement de cette étude que les autres participants ne soient pas tenus au courant de ce que nous allons faire ensemble aujourd'hui.

Si vous n'avez pas de question, nous allons commencer.

-Photos : J'aimerais vous présenter quelques photos sur différents types des lieux de consommation. Je voudrais que par groupes de 2 ou 3 personnes vous classiez ces photos comme vous voulez, selon vos critères personnels. Il n'y a pas des bons ou de mauvais critères. Vous pouvez faire autant de classifications que vous voulez.

-Discussion :

Consumption contexts: personal experiences

Pouvez-vous me parler des dernières fois où vous êtes allés au restaurant ?

 Quel type de restaurant ?

 C'était comment ? Avec qui étiez-vous ?

 Qualité/ prix ?  Quel est le plat que vous avez le plus préféré ?

 Y a-t-il quelque chose qui vous a dérangé ?

 Et au niveau du travail, vous mangez au restaurant, à la cantine ou vous préparez vous-même votre repas ?

 Dans ces lieux, comment est la nourriture ?

 Qu'est-ce que vous préférez manger là-bas ?

o Si sandwich ou snacks : c'est à cause du timing ?

 Vous mangez seuls ou avec des collègues ?

 Qu'est-ce que vous pensez des tests consommateur ?

Relationship between food preparation and consumption contexts

 Qu'est-ce que vous pensez de ces différents modes de préparation : fait maison, prêt à manger, ready-to-heat, surgelés ?

 Comment vous sentiriez vous si vous trouviez ces plats dans un restaurant ou à la cantine ?  Si vous deviez choisir un restaurant, sur quels critères vous basez-vous ?

Relationship between food preparation and culinary skills

 Vous aimez cuisiner et innover des recettes ? Ou c'est une obligation pour vous ?

 A quoi faites-vous attention quand vous achetez des produits ou cuisinez ?

o Type de produit, valeur nutritionnelle, prix, goût, préparation ?

CONCLUSION

Nous avons terminé la séance. Je vous remercie de m'avoir accordé votre temps. Avant partir, j'aimerais savoir si vous pouviez remplir ce questionnaire ? Avez-vous d'autres commentaires ou remarques ? Est-ce que vous auriez aimé discuter d'autres aspects ? Lesquels ? Je vous remercie à nouveau de votre participation. Merci

Autorisation pour l'enregistrement audio/vidéo et l'exploitation des données enregistrées et formulaire de consentement

L'équipe scientifique du Centre de Recherche de l'Institut Paul Bocuse mène des travaux sur les comportements alimentaires et les liens entre l'homme et son alimentation. Les projets portent sur les choix, les perceptions et les pratiques des convives lors de leur repas. Ils s'appuient sur l'analyse de données acquises sur la scène du repas, que ce soit des réponses à un questionnaire et/ou des images recueillies par caméra. L'acquisition de ces données est réalisée sans contrainte, sans simulation, auprès de participants volontaires.

Ces recherches ne sont possibles que grâce au consentement des convives qui acceptent d'être enregistrés. Par conséquent, nous vous demandons votre autorisation à procéder à la passation de questionnaires et à l'enregistrement audio/vidéo, les données recueillies étant définies selon l'étude en cours.

 Autorisation

Je soussigné(e) _____________________________________________________________________ -autorise par la présente le Centre de Recherche de l'Institut Paul Bocuse à enregistrer en vidéo tout ou partie de mon entretien à AgroParisTech, -autorise l'utilisation de ces données, sous leur forme enregistrée et sous leur forme transcrite et anonymisée : a) à des fins de recherche scientifique (mémoires, articles scientifiques, exposé congrès…). b) à des fins d'enseignement universitaire. c) pour une diffusion dans la communauté des chercheurs, sous la forme d'éventuels échanges et prêts de corpus à des chercheurs, moyennant la signature d'une convention de recherche.

-prends acte que pour toutes ces utilisations scientifiques les données ainsi enregistrées seront anonymisées : ceci signifie a) que les transcriptions de ces données utiliseront des pseudonymes et remplaceront toute information pouvant porter à l'identification des participants ; b) que les bandes audio qui seront présentées à des conférences ou des cours (généralement sous forme de très courts extraits ne dépassant pas la minute) seront « beepées » lors de la mention d'un nom, d'une adresse ou d'un numéro de téléphone identifiables (qui seront donc remplacés par un « bruit » qui les effacera) ; c) en revanche, pour des raisons techniques, le projet ne peut pas s'engager à anonymiser les images vidéo mais s'engage à ne pas diffuser d'extraits compromettant les personnes filmées.

Veillez à répondre à toutes les questions

Date :

Bonjour, vous avez été sélectionné(e) de façon aléatoire pour participer à une étude sur l'offre alimentaire dans les restaurants universitaires. Cette étude fait partie des travaux de recherche d'une thèse sur les contextes de consommation.

Les données recueillies seront exclusivement destinées à ces travaux et leur confidentialité est garantie.

Votre participation nous est d'une grande aide.

Merci de répondre à toutes les questions.

Vous avez choisi du pain. Merci de le goûter et d'indiquer votre appréciation à l'aide de l'échelle cidessous.

Quel est votre appréciation du goût de ce pain ?

(0 = je n'aime pas du tout ; 10 = j'aime énormément)

Date :

Bonjour, vous avez été sélectionné(e) de façon aléatoire pour participer à une étude sur l'offre alimentaire dans les restaurants universitaires. Cette étude fait partie des travaux de recherche d'une thèse sur les contextes de consommation.

Les données recueillies seront exclusivement destinées à ces travaux et leur confidentialité est garantie.

Votre participation nous est d'une grande aide.

Merci de répondre à toutes les questions.

Indiquez qu'est-ce que vous avez choisi comme plat principal :

……………………………………………………………………………………………………… Merci de le goûter et d'indiquer votre appréciation à l'aide de l'échelle ci-dessous.

Quel est votre appréciation du goût de ce plat ?

(0 = je n'aime pas du tout ; 10 = j'aime énormément) Aujourd'hui, vous êtes invité(e) à déguster deux versions d'un cake jambon-olives et à répondre à un court questionnaire. Avant et après dégustation, nous vous demanderons de répondre à quelques questions.

Votre participation nous est d'une grande aide et nous vous en remercions.

Q1. Avez-vous des allergies alimentaires ?

☐ Oui ☐ Non

Si vous avez répondu oui, merci de nous faire signe avant la dégustation.

Vous pouvez maintenant déguster le premier cake.

Q2. A quel point avez-vous apprécié ce cake ?

Je n'ai pas du tout aimé ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ J'ai beaucoup aimé

Q3. A quel point ce cake a-t-il répondu à vos attentes ?

Très inférieur Conforme Très supérieur à mes attentes à mes attentes à mes attentes

Veillez à répondre à toutes les questions.

Avant la dégustation

Après la dégustation du premier cake (112)

Vous pouvez maintenant déguster le second cake

Q4. A quel point avez-vous apprécié ce cake ?

Je n'ai pas du tout aimé ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ ☐ J'ai beaucoup aimé Q5. A quel point ce cake a répondu à vos attentes ?

Cette tartelette maison est aux tomates confites et au fromage de chèvre. Elle est faite à partir de produits achetés auprès de nos producteurs locaux, et d'ingrédients provenant de

France.

Q1. A quel point les tartelettes, tartes salées ou quiches sont-elles pour vous des produits familiers ?

(0 = pas du tout familiers ; 5 = très familiers)

A bientôt !

Pour finir

List of tables [START_REF] Lawless | Qualitative Consumer Research Methods[END_REF].

LIST OF TABLES

En ce qui concerne la revue de la littérature, les hypothèses suivantes ont été formulées :

 Hypothèse 1 : les variables liées au contexte ont un poids différent sur l'expérience du consommateur en fonction du contexte de consommation.

 Hypothèse 2 : les variables liées à la consommation dans différents contextes sont intimement liées à la nourriture servie.

 Hypothèse 3 : des différences entre les deux régions devraient être observées en termes de contexte et de variables liées au produit en raison de différences culturelles gastronomiques.

 Hypothèse 4 : des différences entre les deux types de population devraient être observées en termes d'expérience du consommateur en raison d'habitudes de consommation différentes.

Les discussions ont été soumises à une analyse thématique ainsi qu'à une analyse lexicométrique.

Résultats et discussion

L'objectif principal de ce chapitre était d'examiner si l'expérience du consommateur était influencée par ses représentations mentales concernant les aliments dans différents contextes de consommation.

Pour atteindre cet objectif, douze groupes de discussion (n = 86) ont été conduits dans deux régions différentes, Paris et Lyon, avec deux populations différentes : les étudiants et les non-étudiants.

Des différences dans les variables liées au contexte ont été observées entre les contextes de consommation et ont été associées aux attitudes positives et négatives des consommateurs. La convivialité a été mise en avant comme l'une des variables les plus importantes de l'expérience du consommateur. Cependant, tous les consommateurs ne le ressentent pas de la même manière, en fonction du contexte, notamment en ce qui concerne les restaurants gastronomiques où certains  Hypothèse 2 : demander explicitement aux consommateurs d'évaluer les attributs sensoriels dans un contexte de consommation naturelle aurait un effet majeur sur les notes hédoniques pour les produits impliquant une préparation culinaire que pour les produits prêts à l'emploi.  Hypothèse 2 : En condition informée, le cake fait maison obtiendrait des notes hédoniques plus élevées que le cake prêt à manger.

Résultats et discussion

 Hypothèse 3 : L'impact des informations concernant la qualité des aliments (fait maison et prêt à manger) varierait en fonction du lieu de test. Le manque de standardisation dans la manière dont les variables contextuelles doivent être utilisées ou interprétées dans les études contextuelles a été associé à l'absence de cadre théorique derrière ces études. Grâce à une approche multidisciplinaire fondée sur la théorie des perspectives [START_REF] Kahneman | Prospect theory: An analysis of decision under risk[END_REF], nous avons proposé un cadre théorique pour expliquer les observations empiriques relatives aux effets des contextes sur l'évaluation hédonique du consommateur, pour formaliser davantage les effets du contexte afin de garantir une meilleure fiabilité des résultats dans des études sensorielles.

Résultats et discussion

Tout au long de ce travail, nous avons étudié des questions méthodologiques et théoriques qui n'avaient pas encore été examinées dans la littérature. Nous avons défini des avantages et des inconvénients à l'heure de travailler dans des contextes naturels de consommation. Nous avons