Ariel Segall
November 25, 2003
Taste tests are a staple of product marketing in our society, and advertisers and television shows delight in running all sorts of comparison tests in order to demonstrate superiority of one thing or another. The question becomes, how accurate are such tests? Most informal and marketing taste-tests are not actually entirely blind, as would be necessary in a scientific survey. Instead, labels are added, ranging from single lettles and numbers to brand names. Intuition suggests that a strong brand name could affect percieved quality, but how much does any label distort our perception?
Most studies examining the effect of a name on taste are based entirely on brand name effects. One study, looking at generic vs. brand name candies and chocolates, discovered that a roughly 75% preference for the brand name candy in a taste test where brand-distinctive markings were visible changed to a 50%, or roughly chance, distribution when the markings were hidden. Several other studies examining cola preference have shown that subjects with brand loyalty to either Pepsi or Coke overwhelmingly rated cola labelled with their preferred brand as tasting better, even when the samples being tasted were reversed from the labels or identical.
A small but more interesting experiment based on an early 1980s cola commercial asked whether a seemingly unimportant label, such as ``L'' or ``S'' written on a cup, could affect the outcome of a taste test between colas. Surprisingly, a paper survey demonstrated that an overwhelming majority of a classroom of students preferred one letter over the other. When a separate group of students was given a cola taste test with identical samples in labelled cups, a similarly overwhelming precentage said that the sample in the cup with the preferred letter tasted better.
Another taste experiment with ambiguous results was aimed at wine conisseurs. Wine novices and experts were given samples from bottles with cheap or expensive labels which did not match their contents. The wine experts tended to rate the samples from expensive bottles much more highly than those from lesser wines. Although the results were clear, the reasons behing the choice are the subject of much debate; some psychologists claim that the wine experts were entirely led by expectations of quality based on the label, while others say that the difference could be based on legitimate knowledge- certain less pleasant flavours in a high-quality wine could indicate that it would age well, while the same overtones in a cheap wine might simply be unpleasant to drink. Label-based perception effects were clear, but whether those effects were conscious or unconscious was less so.
The effect of names on scents has not been studied much, since brand names are rarely as associated with the scent of a product, and marketing has directly or indirectly driven most research into labelling effects. However, one interesting study demonstrated that for many ambigious scents, switching between a positive and negative label changed not only whether the smell was rated pleasant or unpleasant but also changed the associations the subjects had with the smell. The selection of scents was chosen explicitly for ambiguity, and each sample was a substance both found in a pleasant substance and an unpleasant substance, such as parmesan cheese and vomit. In this study, the same set of subjects were asked to rate and discuss their responses to each smell twice, with different labels, a week apart, without being told that the samples were the same. For a majority of the scents, the associated memories did not overlap at all, and the pleasantness rating of the scent changed by one point or more on a ten-point scale, suggesting that the word associations with the labels carried more weight than the scent itself.
Names are not the only factor to subtly affect a person's perception of flavour or scent. Color and similar visual clues can also change the observed properties of a substance. Unfortunately, studies on the subject have been shown to be inconclusive. Scientists have tested substances including water, sucrose solutions, jellybeans, and cake in dozens of colors looking for a pattern, and gotten wildly varying results.
What has been determined is that color can affect perception of flavour. When tasting lemon-flavoured cake, subjects reported that yellower samples were more strongly flavoured than paler samples, even when the samples were otherwise identical. Along with intensity effects, color can also affect the perceived nature of flavour; subjects are more likely to report that red Seven-up is cherry-flavoured, for example, or that an orange jelly bean tasted like oranges, not cantaloupe. Given a selection of colors which have ``standard'' flavours such as green or purple, a taster is more likely to report the standard flavour than a non-standard one.
However, other aspects have been more controversial. Some studies suggested that particular colors had stronger effects on taste perception so that red, for example, would taste sweeter than yellow. Other studies have contradicted these findings, and demonstrated that in simple sucrose solutions, there was no noticable difference in perceived sweetness between colors.
In addition, there are other factors at work. Supertasters, who are sensitive to extra flavour molecules, are less likely to be confused by color when tasting jelly beans than normal tasters. Many taste experiments do not take into account differences in taste sensitivity, and it is unclear how significant these factors could be in small studies of less than 50 subjects, which appear to be standard for psychological experiments. Also, no studies have analyzed the potential for confusion between the assorted flavours without color factored in.
The common factor among all of these experiments was that the subject's expectations were directly corrolated with their responses. Whether expecting a negative smell, or a lemon flavour, or simply better taste from a favorite brand, subjects reported results which were consistent with what they thought was in front of them. We can see from this that our senses are not purely based on input from the world; our own experience and verbal feedback can change what we think we observe.
This kind of feedback look is not unique to names, or to taste and smell. One of the earliest psychology experiments looking at human perception took olive-colored paper and cut out the shapes of a donkey and a cloverleaf. When asked what color the shapes were, subjects reported that the donkey was brown and the clover green; even when comparing the two shapes side-by-side, subjects overwhelmingly said that the colors were different. Clearly, context can affect our visual senses as well.
Another common factor among these experiments is that positive associations will give positive results. The ambiguous smells were almost always rated more positively by a significant margin when given a positive name. Brands with positive images are rated better than generic brands in non-blind taste tests but not in blind tests, and experiments on diet colas showed significant differences in preferences between unnamed tests and named tests: a 51 vs 44 percent preference split became 23 vs 65 percent when names were revealed. Even the unconscious preference between two letters of the alphabet can dramatically affect the preference between taste samples.
Recent research has demonstrated that different parts of the brain react to the taste of a beverage and the imagined taste. Images of a brand which is closely linked to a person's mental image of themselves can produce a strong positive reaction. A loyal Coke-drinker's brain lights up differently when labelled samples are drunk than when ingesting the beverage without a name. Although the links between self-image, sensory preference, and the brain's reward circuits are only beginning to be explored, the feedback mechanisms causing us to respond differently to the same substance in different contexts is clearly fundamental to our view of the world.
Many of the studies in taste, perception, and branding assume fundamental differences between our perception of different substances. Taste tests and brand comparisons in particular often do not perform double-blind testing, and assume that a straightforward presentation will be sufficient. However, if even a simple letter label can affect our preferences, then the quality of the product may be less important than some environmental factor of the experiment. Double-blind testing suggests a different question, though: which is more accurate a picture of our preferences, the blind test or the labelled test? If context can change our perceptions significantly, then a blind test is returning results which are meaningless in the real world. Either way, we need more information in order to begin to understand our own reactions. I present here some questions which would provide interesting results in this area if properly researched.
Exactly how much influence does positive association have?
In a plain taste test which asks which of two samples are preferred, a known brand is more likely to be chosen. How much does our brand loyalty really affect our taste buds, though? Would asking for a taste rating on a one-to-ten scale produce dramatic differences between the blind and labelled test, or would the differences be small? Will we rate a favorite brand over an unfavored brand only in cases where the compared samples are extremely similar, or can we add an unpleasant substance to the favored brand and not change the result? How much of an unpleasant change would it take before the label preference became less relevant than the blind test results?
How small and subtle an association is enough to affect our perception? Certainly, most people prefer the smell of parmesan cheese to that of vomit, but do we prefer summer to winter? If letters can have effects on our preferences, can numbers? Does the font of a label change our associations with a word, and will that change our preference for a product? How subtle a change will be reflected in our response? Marketers and propagandists would love to know the answer, but if we could make healthy food more appetizing to children or medicine more palatable, the results would be worthwhile.
Does the positive association feedback effect apply to all senses?
We've seen that positive associations can change our perceptions of taste and scent. Expectations, such as the donkey and clover's color difference, clearly can apply to vision also. Can positive word association also affect our preferences for color? Shape? Texture? Will a child prefer a crayon called Goldenrod to one called Dark Yellow? Will an adult prefer a fabric called synthetic suede to one called rayon-polyester blend?
Can we trigger the same sorts of association-based differences with other mechanisms, such as shape and texture?
We have established that name and color can change our perception of flavour. Could the shape of the container we drink out of change our preferences? The texture of candy? The sound the packaging makes? All of these are aspects of brand and marketing, and one European design research team established that it is possible to create packaging designs which reflect the same kinds of associations as specific desserts. Does the pudding in the pudding-shaped package taste better than the same pudding in a generic square package, though? Can we give vanilla pudding the same associations we have with tiramisu by putting it in a tiramisu-shaped container?
Although many studies and taste tests have investigated the effects that names and colors have on human perception, few have looked at the larger patterns of mental associations and the context created by labels. Surveying even a small handful of studies reveals that our experiences reflect our expectations in sometimes unexpected ways. Without more information about how and how much our expectations and associations can shape the way we see our world, we cannot discover what truly influences us.
Bonham, P., Greenlee, D., Herbert, C.S., Hruidi, L., Kirby, C., Perkind, A., Salkind, N., Wilfong, R. (1995). Knowledge of Brand and Preference. Psychologica l Reports, 76(3), 1297-98.
Woolfolk, M.E., Castellan, W., Brooks, C. (1983). Pepsi versus Coke: labels, not tastes, prevail. Psychological Reports, 52, 185-6.
Alley, R., Alley, T. (1998). Influence of physical state and color on perceiv ed sweetness. Journal of Psychology, 132(5), 561-8.
Overbeeke, C.J, Peters, M.E. (1991). The taste of desserts' packages. Perceptual and Motor Skills, 73, 575-80.
Koch, C., Koch, E. (2003). Preconceptions of taste based on color. Journal of Psychology, 137(3), 233-42.
Herz, The influence of verbal labeling on the perception of odors: Evidence for olfactory illusions? Perception, 30(3), 381
Unknown, Wijeya Newspapers Financial Times, http://www.dailymirror.lk/2003/09/04/ft/10.html
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