why do we like what we like?
TRANSCRIPT
Journal of the Science of Food and Agriculture J Sci Food Agric 81:10±16 (online: 2000)
ReviewWhy do we like what we like? †
David J Mela*Unilever Research Vlaardingen, NL-3130 AC Vlaardingen, The Netherlands
(Rec
* Co† Presens
# 2
Abstract: Why do we ®nd certain foods more pleasurable than others? Interactions of food components
with human biology and with social and eating contexts give rise, in some predictable ways, to
relatively stable individual food likes. While sensory and consumer research have traditionally focused
on measuring existing likes, a better understanding of their basic determinants can provide ideas and
tools to better predict and in¯uence how likes may develop and change. The liking for a particular food
or set of foods largely re¯ects the prevailing cultural environment and personal experiences, which
generate variation in the opportunities and likelihood for speci®c biological predispositions and
learning processes to operate with regard to particular foods. These learning processes may be largely
in¯uenced by the intrinsic orosensory or nutritional attributes of foods themselves, as well as
characteristics of the situational contexts in which foods are experienced. Liking is one factor
contributing to the desire to eat a food, and ultimately to food selection. Current knowledge of these
processes is brie¯y reviewed, with suggestions of potential implications for understanding and
predicting food acceptance and choice.
# 2000 Society of Chemical Industry
Keywords: likes; food; preferences; acceptance; taste; ¯avour; sensory; boredom
INTRODUCTIONThe anticipation and sensation of pleasure derived
from food consumption are critical in¯uences on food
acceptance and selection. Domestically, agriculturally
and industrially, high proportions of food develop-
ment and production resources are invested in
ensuring that products will be highly `liked' when
eaten. Although a variety of common procedures are
used to identify how well different combinations of
sensory qualities are liked, there can be considerable
variance between and within individuals and groups,
including dynamic changes as a result of experience
with the food itself. An understanding of the mechan-
isms by which likes are acquired may help in under-
standing this variance, and may be applied to identify,
predict and possibly in¯uence potential changes in
liking over time, to ensure that food products deliver
long-term satisfaction to consumers.
WHAT DO WE MEAN BY ‘LIKING’ AND‘PREFERENCE’?`Liking' is used here to refer to an immediate
qualitative, affective (hedonic) evaluation of a food;
the degree of experience of pleasure or displeasure.
Liking is judged against an internal reference scale for
intensity and (paraphrasing Feather1 on `valence')
eived 6 March 2000; accepted 1 September 2000)
rrespondence to: David J Mela, Unilever Research Vlaardingen, NL-3sented at the 25th Anniversary meeting of the Society for Chemicaory research: expanding the horizon’, London, 26 October 1999
000 Society of Chemical Industry. J Sci Food Agric 0022±5142/2
refers to the perceived attractiveness or aversiveness of
speci®c objects and events within the immediate
situation, linked to a speci®c context and a present
timeframe. Affective responses are `¼a feeling state
that occurs in response to a speci®c stimulus¼with a
potential range of cognitive effort'.2 The latter state-
ment highlights the fact that affective responses are not
necessarily constant for the same sensory stimulus,
and often re¯ect the situation (context) in which the
evaluation takes place, and other attitudes, beliefs and
expectations (cognitions) of the assessor.
In market research it is often a recollection of liking
for a speci®c food or food type in general, rather than
actual taste experience, that is evaluated, eg `How
much do you like pepperoni pizza?'. Evaluations made
during actual eating (while I taste the pizza) or as
recalled (when I think about the pizza later) may or
may not closely correspond. Although product devel-
opment research tends to focus on actual eating, the
recalled liking may be of interest, since purchase
decisions are rarely made on the basis of immediate
tasting.
Although the terms `liking' and `preference' are
often used interchangeably, it is useful to make a
distinction. `Preference' is better used to express
choice: an indication that amongst two or more
alternatives presented in a given time and context,
130 Vlaardingen, The Netherlandsl Industry Sensory and Consumer Science Group, ‘Consumer and
001/$30.00 10
Table 1. Unlearned affective responses to oronasal sensory stimuli
Gustatory (taste)
Taste quality `Innate' response Development
Sweet Like In utero
Food likes
certain options are more desirable than others. A
product may be preferred over another, even though
neither is liked. Or a product may actually not be liked
as much (ie does not taste as nice) as another, but
nevertheless preferred and purchased for other reasons
(eg health, price, packaging, etc).
Confusion arises because the term `preference' is
commonly used to indicate one or all of three differing
measures of food acceptance.
1. `Preference' is sometimes used to mean liking (for
sensory attributes): hedonic response, as in food
`preference' tests.
2. `Preference' is sometimes used to mean choice (in a
product test): selection of one item from amongst
alternatives, eg in a ranking or selection test, based
perhaps on many different criteria and product
attributes besides just tasting.
3. `Preference' is sometimes used to mean purchasedecisions: what consumers actually choose to buy; eg
`consumer preference' in marketing data.
As noted, `preference' is often (mis)used as a
synonym for `liking'. In such cases it seems better
simply to use the latter term. Liking of a product
contributes to the formation of expressed preferences
and purchase behaviours, but is only one of many
contributors. This ambiguity causes miscommunica-
tion and perpetuates misunderstandings. For example,
there is often surprise and disappointment when the
results of `preference' tests (liking tests) fail to predict
actual consumer `preference' (purchase decisions); the
latter clearly has many more determinants than liking
alone. As a facile illustration, the sensory analyst may
®nd that most people `prefer' lobster to canned tuna
(ie liking, measured by taste tests), but the market
researcher knows that the same people clearly `prefer'
canned tuna to lobster (ie purchase decisions,
measured by frequency and volume bought).
In addition, the notion of `desire' becomes useful in
discussing variations in the feelings of wanting, the
anticipation that eating a particular food would be
pleasurable. For example, although an individual's
general liking (taste test) for chocolate may be quite
high and stable, the actual desire to eat it can still vary
considerably across time and situations. Similarly,
most wine a®cionados might express rather low desire
for their favourite bottle if they were woken from a
deep sleep and offered it for breakfast. This distinction
between liking and desire, and its implications, are
explored further below.
Salty Like 4±6 months postnatalSour Dislike (?) In utero
Bitter Dislike In utero� later maturation
`Umami' Context-dependent? Uncertain
Olfactory (smell)
No unlearned affective odour responses established
Chemesthetic (mechanical, thermal, nociceptive)
Pain avoidance inborn; no other unlearned affective responses
(eg for textures) established
‘INNATE’ ASPECTS AND EARLY ACQUISITION OFLIKESHumans have a relatively narrow range of unlearned
likes (biologically predestined and clearly independent
of any prior exposure). Although there are some
known genetic sources of variance, cultural similarities
in liking for food sensory qualities largely re¯ect shared
experiences rather than any unique shared biological
J Sci Food Agric 81:10±16 (online: 2000)
characteristics. Data on presumed inborn (ie present
at birth) responses to basic chemosensory stimuli
(primarily simple taste and odour compounds) come
from studies on full- and pre-term infants, using a wide
variety of methods to explore both discrimination and
(presumed) liking. The relevant research methods and
the lines of support are thoroughly discussed in reviews
by Beauchamp and colleagues.3,4
TasteIt appears that humans are born with positive hedonic
responses to at least one taste quality, sweetness, and
probably a dislike for sour and (most) bitter taste
stimuli. (These taste qualities re¯ect descriptors
commonly applied by adults to the same stimuli.)
Ability to sense (and probably an inborn liking for)
salty stimuli develops a few months after birth, and
there may also be some postnatal maturation of bitter
taste perception. The situation is uncertain with
`umami' (the savoury taste quality of monosodium
glutamate (MSG) and ribonucleotides, often con-
sidered a ®fth `basic' taste quality). Among infants,
MSG alone in water appears to be disliked relative to
plain water, but more complex mixtures containing
MSG may be neutral or perhaps liked relative to the
same mixture without MSG.5 These `innate' taste
responses are characterised in Table 1. For several
reasons, it is logical to presume that the normal
neonatal hedonic responses to these basic qualities are
truly unlearned, but that does not exclude these
unlearned responses from modi®cation by later devel-
opmental changes, experience and learning.
There are further developmental changes in taste
responses during childhood and adolescence which in
part re¯ect inborn biological predispositions. To some
extent, though, these may be secondary to differences
in social and cognitive maturity, in addition to any
differences in the peripheral sensory receptors or
central affective signals. The vast bulk of relevant
research has focused on sweet and salty tastes, where
cross-sectional and longitudinal studies con®rm the
anecdotal observation that young children often prefer
a higher sweetener level than adults,6 and this is also
11
Figure 1. A simple general scheme for the acquisition of food likes.
DJ Mela
true for salt in many contexts.7 Although this may be
taken to indicate a liking for greater sweetness by
children, it is quite plausible that this actually re¯ects
lower perceived intensity of sweeteners.8 That is,
compared to adults, children may simply require
higher levels of sweeteners within foods to achieve
the same perception of sweetness intensity.
SmellIn contrast to taste, there is no compelling evidence for
any inborn, unlearned volatile ¯avour (dis)likes in
humans.4,9 However, there has also been far less
research conducted with odours. This is in part due to
problems of stimulus control, and constraints on the
types of materials to which infants may be exposed, as
well as the lack of commonly accepted, discrete
categories of stimuli from which representative com-
pounds might be easily selected for testing. There are
considerable dif®culties in interpreting many of the
relevant research results.9
Although liking of food-related and other aromas
appears to show, with some exceptions, broad general
similarities across different human populations,10,11
this may better re¯ect shared experiences with
common environmental odours than a speci®c con-
genital predisposition. Without prior experience,
newborns do not exhibit clear hedonic responses to
representative odours deemed highly pleasant or
unpleasant by most adults.9 However, the capacity to
acquire sensory hedonic responses is apparent from
very early in life, and newborn humans and animals
can recognise and respond preferentially to speci®c
maternal and environmental odours within hours of
birth.12±14 These responses can be in¯uenced by
prenatal (in utero) and early postnatal (breast-feeding)
experience, including secondary exposure to ¯avours
in the maternal diet. Within a few days, breast-fed and
bottle-fed infants showed differential degrees of
response to the odours of their respective food
sources.13,14 These data are generally consistent with
the view that even `universal' environmental and food
odour (dis)likes are not inborn but are acquired. The
long-term implications of these early experiences, and
potential for in¯uencing later food likes, are potentially
important but not established.
The extent to which the apparent liking for fats or
other texture-related components in foods is inborn or
acquired is not resolved. Several studies suggest that
rats may express an apparent unlearned liking for fat-
associated, `greasy' textures at birth or soon there-
after.15 However, other data show that these hedonic
responses can be acquired, and it is also conceivable
that apparently `innate' responses could re¯ect acqui-
sition occurring in utero or, perhaps more importantly,
during suckling. The relevant human studies are
reviewed by Catt,16 whose own data indicate that
6-week-old bottle-fed infants do not discriminate or
show any clear preferential responses in relation to fat
content of milk formulaes. An acquired liking for fat-
related textures or ¯avours appears to be best
12
explained by the post-ingestive effects of fats (eg
energy density), or perhaps through early associations
with milk, or with lubrication, ease of swallowing, or
other positive hedonic experiences (see below).
MERE EXPOSURE OR MORE EXPOSURE?The evidence reviewed above supports the view that
liking for particular combinations of sensory qualities
is largely acquired through experience. Even the few
inborn responses are subject to change through
experience, via processes depicted in Fig 1 (examples
being development of liking for black coffee or
alcoholic beverages). In this scheme the socioeco-
nomic and cultural environment is viewed as having a
primary role in setting up the opportunities and
contexts for particular sensory experiences, ie this
determines what foods will be experienced and the
frequency and conditions in which this occurs.17 It is
the nature of these experiences, and of their associa-
tion with particular sensory attributes, which is seen as
being a central underlying driver of changes in liking.
This can potentially account for both individual
differences and the similarities within cultures. The
genetic predisposition includes inborn likes or dislikes,
but also possible variation in the biological propensity
for acquiring and expressing certain new, learned
associations.
Mere exposure?Do food likes develop and change through simple,
`mere' exposure to them? `Mere exposure' (ME) is
commonly invoked as a post hoc explanation for
observed food likes, in accord with the common
experience that `I got used to it'. As suggested in Fig
1, this view implies a direct bridge between experience
and liking, without clear involvement of any particular
reinforcing elements. There is in fact a considerable
body of evidence for a de®ned `mere exposure'
phenomenon from non-food areas, especially words
and pictures.18,19 However, most research showing
ME effects has been carried out under conditions
J Sci Food Agric 81:10±16 (online: 2000)
Food likes
which exclude other types of reinforcement, and,
indeed, the ME effect may be strongest when initial
experience is indirect and ephemeral and not even
recalled.19,20 In contrast, exposure to food items in
normal eating is rarely `mere'. Instead, it is usually
associated with thoughts, social situations, post-
ingestive effects and other factors which may easily
underlie or outweigh any so-called `mere exposure'
effects. Eating therefore provides clear opportunities
for other processes (such as associative learning,
discussed below) to occur. It may therefore be argued
that `mere exposure' is generally being used as a
convenient description, rather than a useful explana-
tion of the basis for observed changes in food liking,
when better explanatory alternatives exist.
Associative conditioning?Extensive evidence from experiments with animals
and growing evidence from human studies support the
view that liking for combinations of sensory attributes
in foods is largely acquired as a result of repeated
pairing with other stimuli or events via associative
conditioning.20±28
The liking for speci®c foods may, for example, be
linked to biological `cost' or bene®t derived from their
consumption, re¯ecting post-ingestive effects of foods.
There is strong evidence for this process in the
formation of intense dislikes from studies of learned
food aversions. In this case the association of a food
with acute illness (especially gastrointestinal upset)
can trigger a dramatic change in liking for previously
neutral or even well-liked foods.26,29 This may explain
many common, apparently idiosyncratic individual
dislikes for the ¯avour (usually) of speci®c foods.
Positive, `rewarding' psychobiological effects may
contribute to the formation of likes. The development
or maintenance of liking as a result of pharmacological
effects of caffeinated or alcoholic beverages may be
examples for humans (though it should be noted that
caffeine may ultimately function via alleviation of
withdrawal, rather than necessarily a positive effect perse).30 The metabolic effects of energy or speci®c
nutrients may also serve to reinforce the acquisition
of likes. Studies with young children, for example,
have demonstrated the development of relative pre-
ferences for speci®c ¯avours paired with versions of
foods higher in energy content, versus ¯avours paired
with lower-energy versions.31±33 However, differences
in energy content may not be so important in the
development and maintenance of food likes amongst
adults under normal eating conditions (Stubenitskyk etal, unpublished). This mechanism may be more robust
in children because of their limited prior experience
with ¯avours or their greater sensitivity to differences
in the physiological effects of food energy. Food
composition, beyond direct effects of pharmacologi-
cally active ingredients, may also produce differential
psychological (eg mood and performance) effects
which could feed back positively into food likes. These
J Sci Food Agric 81:10±16 (online: 2000)
are areas which are currently of academic and
industrial interest.
In addition to effects related to the composition of
the food itself, changes in liking for foods may also be
acquired as a result of associations with other aspects
of the eating experience and context (so-called
`evaluative conditioning').34 Situational cues may also
prompt hunger in general or the desire to consume a
particular food. Recent work in this area in particular
suggests new avenues for understanding and predict-
ing the acquisition of likes.
Foods are constantly experienced in association
with other stimuli that are (already) more or less liked,
eg with events, social or eating situations and other
foods or ¯avours. It seems plausible that the pairing of
foods with such stimuli couldÐindependently of the
composition or the post-ingestive consequences of the
food item itselfÐgenerate directional changes in liking
for the food itself via evaluative conditioning.24,27,28,34
Within marketing research, similar types of associa-
tions are cited as justi®cation for linking products with
popular entertainment or sports ®gures and attractive
people, music or illustrations.35,36 There have been a
number of relevant studies which have speci®cally
used these procedures to in¯uence hedonic judge-
ments of odours and food-related stimuli.24,27,28,37
Within a given food, `¯avour±¯avour' conditioning
(pairing of an initially neutral food or ¯avour with
other, already liked or disliked ¯avours) may foster
conditioned shifts in liking for the previously neutral
item.24,27
The concept of evaluative conditioning is attractive
because it presents a `natural' mechanism for learning
about food contexts and combinations. There are
probably many opportunities for relevant associations
to occur in common for individuals within cultures,
but also differences for families and individuals, so this
®ts well with the observed characteristics of variation
in food likes across and within populations. However,
although description of evaluative conditioning makes
intuitive and theoretical sense, the actual empirical
support at this time is rather limited and inconsis-
tent.38
LIKING, DESIRE AND BOREDOMIn addition to potential positive effects of exposure, it
is widely recognised that very high frequencies of
experience may reduce food acceptance, a phenom-
enon commonly characterised as `boredom'. When
applied to speci®c products, a central question is
whether this re¯ects characteristics of the food or the
concept, ie whether the primary determinants of
`boredom' are essentially physiological or cognitive.
In other words, is there a real change in the actually
experienced affective response to the food, or does the
idea of eating the food become less attractive?
The term `boredom' is equally applied to events and
phenomena occurring over short (eg within one or
several meals) and long (eg over several weeks or
13
Figure 2. Schematic diagram of factors influencing ‘desire’ to eat aparticular food.
DJ Mela
months) timescales; however, these do not necessarily
represent the same phenomena or share similar causes.
To date, most of the relevant academic research with
foods has focused on very short timescales where
immediate physiological effects may predominate,
whereas cognitive and emotional processes may be
more relevant over longer periods of time.
Short-term effects on food acceptanceThe most prominent stream of research addressing
short-term effects of foods on food acceptance has
been oriented towards the phenomenon of `sensory-
speci®c satiety' (SSS). SSS is often used to describe a
decrease in acceptance ratings and choice of a speci®c
food or sensory quality as a result of immediate prior
exposure or consumption.39±42 In typical SSS experi-
ments, subjects are exposed to a speci®c food, perhaps
several times in a short period, and then make some
sort of acceptability judgement (eg liking, choice,
desire to eat) for that item versus others. Relative to
pre-test ratings, subjects usually indicate reduced
acceptance for foods just experienced and foods with
sensory qualities (colour, shape/appearance, texture,
¯avour) similar to them, compared to other (less
similar) alternatives.42,43
Relatively reduced ratings of `pleasantness' of foods
just eaten seem congruent with everyday experience:
consumption of a food often blunts desire for that
same item, while desire to eat other, different foods is
retained. However, the cause, interpretation and
relevance of the observation are open to debate. It is
largely presumed within the SSS literature that this
re¯ects a primary shift in affect (the item actually does
not taste as nice anymore), and this is indeed plausible.
However, other researchers have argued that con-
sumption of a food under typical SSS conditions
primarily in¯uences wanting or desire to eat the food,
as distinct from a change in the actual (sensory)
pleasantness derived from eating it.44,45 These points
may re¯ect a more general problem in the interpreta-
tion of common hedonic rating scales, namely the
failure (by subjects and investigators) to distinguish
amongst motivational or other attitudinal judgements
and judgements of affect (liking) alone. That is, tests
often fail to allow differentiation amongst liking
(tasteÐactual or anticipated), preference (eg based
on health or ethical considerations) and desire (want-
ing to eat the item now, for any number of reasons).
In general, the SSS literature leans heavily towards
assigning neural and biological explanations for the
observations, consistent with the emphasis on de-
creased effect. However, even very strong proponents
of this view of SSS leave open the possibility of
cognitive involvement.40,41 This is potentially an
important issue, particularly when the concept is
extended to longer timeframes. If `boredom' with a
food re¯ects relative changes in sensitisation or
habituation to some set of its attributes, then a greater
diversity (`complexity'?) or a differing set of attributes
within the same product should largely slow or prevent
14
this process. On the other hand, repeated consump-
tion of a single item (or quite similar alternatives) does
not ®t within normal rules of cuisine and is therefore
culturally inappropriate. Thus reduced ratings may
re¯ect feelings about the overall eating situation and
motivation rather than (or in addition to) the food
sensory quality.
If short-term and long-term food `boredom'
phenomena are fundamentally different, then it is
not surprising that short-term tests fail to capture or
predict longer-term events.46
Food desire, ‘boredom’ and monotonyIn considering the problem of `boredom' in a more
realistic sense (eg repeat product use over a period of
weeks or months), it is necessary to look more closely
at the distinction between liking and `desire to eat' and
consider which of these is captured in the concept of
food `boredom'. Liking is clearly one contributor to
`desire', which presumably carries a component of
anticipated pleasure. However, liking is clearly not
enough to predict desire. We may like ®sh soup or a
favourite wine but feel no desire to consume these at
breakfast. Thus desire can also be strongly in¯uenced
by feelings of appropriateness;47 that is, whether a food
matches the situation and context. The matching of
foods and use-contexts is largely determined by
cultural and social conventions. Furthermore, there
are psychophysiological conditions that prompt desire
irrespective of other factors. One example is thirst, but
this may also include more subtle effects such as a
feeling of desire for coffee or chocolate prompted by
mood state or hunger.25,30 In this case, consumption
of particular foods may have the effect of altering a
`need state', and this may also act as a reinforcer for the
development of likes. A simple representation of these
relationships is depicted in Fig 2.
`Boring' may be used by consumers as a description
of the common, routine, unexciting nature of certain
foods, but also to characterise consumption at an
undesirably or inappropriately high frequency. One
possibility is that `boredom' in the latter sense re¯ects
consumption at a level inconsistent with accepted
norms; that is, once an `appropriate' and `normal'
pattern and frequency of consumption are established,
J Sci Food Agric 81:10±16 (online: 2000)
Food likes
further increases in eating frequency are resisted and
may be incorporated into expressions of `boredom'.
This sees perceptions of `boring' as largely cognitive in
origin, attributed to foods in relation to their role in
cuisine.
Data of Stubenitsky et al48 provide some support for
this view. In this research, consumers were given
chocolate bars (three bars per week) and sausages
(once per week) for consumption at home over a 10
week period. There were no changes in hedonic ratings
for either product over the period of required
consumption; however, throughout this same period,
`boring' ratings increased at a relatively consistent rate.
The slope of this increase appears lower for the
chocolate than sausages, despite the fact that the
chocolate was eaten at a much higher (but more
culturally typical) frequency. The data clearly show a
dichotomy between liking (unchanged) and boredom
(rising), and it seems reasonable to expect that the
latter would be a better predictor of changes in repeat
purchase intent. Data of Schutz and Pilgrim49 may
also be viewed as supporting a culinary or cultural
assignment of `boredom'. They found that foods
which are known by custom to be appropriate to eat
every day (cereals, bread, etc) were most resistant to
boredom-associated decreases in rated acceptability.
Porcherot and Issanchou50 reported that consumption
of speci®c ¯avours of crackers over 3 months at home
generated no change in `liking' ratings for four of ®ve
varieties. The interesting exception, where liking
increased, was the one ¯avour which initially scored
lowest for liking, appropriateness and familiarity.
Although several major theories relating to repeat
exposure, variety-seeking and the development of
boredom focus on stimulus `complexity',50±52 the
`complexity' measures in this study were unrelated to
changes in liking over time. However, it may be that
novelty, rather than complexity, is a more central
issue.53
Perhaps because of this blurring of liking with desire
to eat, consumers themselves may not be particularly
good at judging in advance the likely extent of changes
in liking with repeated experience. In the work of
Kahneman and Snell,54 where subjects were told they
would (and did) eat the same ¯avour of ice cream each
day for 8 days, subjects tended to predict greater
declines in liking than they actually experienced. This
is again consistent with the view that it is the idea of
eating a food which is primarily affected by repetition,
rather than an actual appreciation of its sensory
characteristics.
The causes of perceived food `boredom', and its
relationships with repeat product purchase behaviour,
clearly warrant further study.
CONCLUSIONS: WHY DO WE LIKE WHAT WE LIKE?The liking for a particular food or set of foods largely
re¯ects the prevailing cultural environment and
personal experiences, which generate variation in the
J Sci Food Agric 81:10±16 (online: 2000)
opportunities and likelihood for speci®c biological pre-
dispositions and learning processes to operate with
regard to particular foods. Humans have a limited set
of inborn taste likes and dislikes, and even these are
modi®ed through experience. The liking for speci®c
sensory qualities in foods is largely acquired through
their association with a range of possible reinforcers,
which include intrinsic components of a food as well as
aspects of the context in which it is eaten. Knowledge
of these and the relevant underlying mechanisms,
largely derived from the behavioural science literature,
can potentially be used to evaluate, predict and alter
product acceptance.
Liking is, however, only one contributor to the
desire to eat a speci®c food, and to its eventual
selection from many possible alternatives. Desire to eat
an item may also re¯ect cognitive factors, such as
appropriateness of the food for a situation, and `need'
state, such as physiological conditions (eg thirst). Both
commercial and academic food acceptance research
could be advanced by greater clarify of thought in
differentiating amongst the different determinants of
food choice. Furthermore, there is clearly a require-
ment for food acceptance research to expand beyond
its emphasis on short-term phenomena, which may
not capture events occurring with repeat exposure over
longer timeframes, and under more realistic eating
conditions.
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