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Food acceptance: The role of consumer perception and attitudes 2
E.Costell, A. Tárrega, S. Bayarri 3
Physical and Sensory Properties Laboratory. IATA.CSIC 4
PO Box 73. 461000 Burjassot. Valencia. SPAIN 5
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Abstract 9
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The process by which man accepts or rejects food is of a multi-dimensional 11
nature. In complex food matrices, it is not always easy to establish relationships 12
between the individual chemical stimuli concentration, physiological perception 13
and consumer reaction. Consumers’ responses to food are not only based on 14
the sensory characteristics of the product and on their physiological status but 15
they are also related to other factors, such as previous information acquired 16
about the product, their past experience, and their attitudes and beliefs. This 17
paper discusses different methods to obtain information about consumer 18
perceptions, attitudes, beliefs and expectations. 19
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Keywords: consumer response, perception, attitudes, expectations 22
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Introduction 24
Sensory quality should be considered as a key factor in food acceptance because 25
consumers seek food with certain sensory characteristics. The acceptance of a 26
food will depend on whether it responds to consumer needs and on the degree of 27
satisfaction that it is able to provide (Heldman, 2004). The process by which man 28
accepts or rejects food is of a multi-dimensional nature. Its structure is both 29
dynamic and variable, not only among different individuals within a group but also 30
within the same individual in different contexts and periods of time. Acceptance of 31
a food is basically the result of the interaction between food and man at a certain 32
moment (Shepherd, 1989). Food characteristics (chemical and nutritional 33
composition, physical structure and properties), consumer characteristics (genetic, 34
age group, gender, physiological and psychological state) and those of the 35
consumer’s environment (family and cultural habits, religion, education, fashion, 36
price or convenience) the influence of consumers´ decision to accept or reject a 37
food (Shepherd, 1989; Shepherd and Sparks, 1994). Apart from the 38
characteristics of the food itself and the sensations consumers experience when 39
ingesting it, a consumer’s purchase choice and even the degree of pleasure when 40
consuming it can be influenced by their attitude and opinion about the nutritional 41
characteristics (Bruhn et al., 1992), safety (Resurreccion and Galvez, 1999; 42
Hashim et al., 1996, Wilcock et al. 2004) and even the trademark (Guerrero et al. 43
2000) or price (Caporale and Monteleone, 2001) of the product. Other aspects of 44
consumer response to food must also be considered. For example, the 45
relationships that exist between taste genetics, taste function markers and 46
preference or food intake (Dinehart et al, 2006) or the increase in acceptability due 47
to habitual consumption (Luckow et al., 2005; Stein et al., 2003) or whether the 48
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food fulfils consumers’ expectations of sensory quality (Cardello, 1994). All of 49
these influence consumer response and can lead to either repeated consumption 50
or rejection of a product 51
During food consumption, the brain receives different sensory inputs (visual, 52
olfactory, gustatory, tactile, trigeminal) and the information from physiologically 53
distinct sensory modes is integrated in the final sensory perception (Prescott, 54
2004, Small and Prescott, 2005). For consumers, each perceived sensation 55
responds not only to a certain sensory input but also to the other inputs 56
perceived simultaneously and to physical or perceptual interactions among 57
them. Delwiche (2004) have reviewed how all these sensations interact, both at 58
the perceptual and the physical level, and discuss the impact that each one of 59
them has on flavour rating. Though all these inputs influence flavour perception, 60
through physical or perceptual interactions, the interaction between taste and 61
odour is so strong that they jointly constitute the flavour perceived. When either 62
the taste or the odour compound of a highly familiar odour-taste pair is 63
presented in isolation, it may elicit weak ratings of the missing component. For 64
example, odours that are normally present together with sweet tastes in mouth, 65
such as vanilla, are commonly described as “sweet” odours. This perception 66
does not result from any direct physiological effect of such odours on taste 67
receptor, but it reflects a central neural process which appears to be based 68
upon simultaneous associations between taste and smell. This type of learning 69
effect has also been observed for sour and bitter tastes, resulting in odours that 70
smell “sour” and “bitter”, respectively (Sundqvist et al, 2006). A distinctive 71
characteristic of odour-taste integration is that for effect enhancement to occur, 72
the odour and taste components must be perceptually congruent (White and 73
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Prescott, 2007). In studies using functional magnetic resonance imaging (fMRI), 74
de Araujo et al, (2003) and Rolls (2005) located where interactions between 75
taste and odour stimuli take place in the human brain. Two taste stimuli and two 76
odour stimuli were delivered unimodally or in different combinations. The results 77
obtained revealed that while some brain areas respond to either taste or retro-78
nasal olfactory stimuli, other brain areas respond to both. De Araujo et al, 79
(2003) also showed that correlations with consonance ratings for smell and 80
taste combinations and for their pleasantness were found in the medial anterior 81
area of the orbitofrontal cortex. They concluded that these results provide 82
evidence for the convergence of taste and olfactory stimuli to produce flavour 83
and reveal where the pleasantness of flavour is perceived in the human brain. 84
Moreover, flavour perception is highly dependent on both the subject’s past 85
experience with specific odour-taste combinations (the origin of congruence) 86
and on the cognitive factors that determine whether the flavour elements are 87
combined or not (Prescott, 2004). 88
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In complex food matrices, it is not always easy to establish relationships between 90
the individual chemical stimuli concentration, physiological perception and 91
consumer reaction. It is difficult to make predictions as to the possible perceptible 92
differences between products differing in composition and/or structure, as a result 93
of changes in formulation or processing. It is even more difficult to predict to what 94
degree the consumer will accept it and It is necessary to combine information on 95
different factors: concentration of both volatile and non-volatile stimuli, structure 96
and other physical characteristics of the food matrix, physico-chemical 97
mechanisms governing the release of taste and odour compounds, product 98
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modification during oral food processing, sensory techniques to ascertain how 99
flavour is perceived and how this perception affects the final acceptance of the 100
product under study. Regarding this last point, one must bear in mind that when 101
consumers eat food their responses are not only based on the sensory 102
characteristics of the product and on their physiological status but they are also 103
related to other factors, such as previous information acquired about the product, 104
their past experience, and their attitudes and beliefs (Aaron et al., 1994; Cardello, 105
1994; Zandstra et al., 2001; Schifferstein, 2001; Barrios & Costell, 2004; Wilcock 106
et al., 2004). The influence of attitudes, beliefs and opinions on food choice and 107
purchase is especially important in the acceptance or rejection of some types of 108
food such as organic food, genetically modified food or functional food, which are 109
presented to the consumer as a possible alternative to conventional food 110
(Roininen & Tuorila, 1999, Connor & Douglas, 2001; von Alvensleben, 2001; 111
Pearson, 2002). Consumer acceptance of organic, genetically modified or 112
functional food is far from being unconditional. Their benefits may provide added 113
value to consumers but cannot outweigh the sensory properties of foods (Siró et 114
al 2008). 115
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In a simplified manner, consumer response to a given food is mainly defined by: 117
1) a sensory component, related with the sensory properties of the product; 2) 118
an affective component, responsible for positive or negative response towards a 119
product, 3) a cognitive component, coming from the knowledge and opinions 120
about a product; and 4) a behavioural component, involving intentions or 121
actions, defining how willing a consumer is to do something in certain situations. 122
The sensory component reflects an individual’s sensory perception of the 123