Recently, I was at a restaurant in Costa Rica, and I noticed some commotion at a table nearby. First, a server had presented the table with a bottle of red wine, and poured some into an older man’s glass for him to sample. As the table watched with anticipation, the man swished the wine around in his glass and took a sip. Furrowing his brow, he shook his head. Dismayed, the waiter hurried over to a group of other waiters, who solemnly placed the wine behind the bar, as if they were placing a petulant child in the corner until it learned to behave.

As not such an oenophile myself, I was initially awestruck at the sophistication of this elderly gentleman. When seeing how the table and the waiters observed his judgment, I was reminded of biblical scenes, of a prophet spreading the word of God to the masses. To have such a refined palate must be to achieve the pinnacle of sensory experience, and the epitome of cultured tradition!

But what really was happening when that man tasted the wine? Did he truly taste the wine, or was he simply in a bad mood? Indeed, say that I (or some other uninitiate) decided to begin making such judgments, but arbitrarily – would anyone know the difference? Is the whole mystique of wine expertise built upon a bed of lies?

Fortunately enough, psychologists in recent years have researched extensively whether there is any objective basis to wine tasting. In 2001, Morrot and colleagues presented the theory that smell alone is unlikely to provide enough information for a conscious decision – instead, it helps to modulate the other senses. By this theory, maybe smell alone could not distinguish an orange scent from a lemon scent, but seeing an orange or yellow-colored drink would clear up what the scent was. To test the assumptions of this theory, the researchers rather deviously used food coloring to color white wine red and served it to 54 tasters, all undergraduates from the Faculty of Oenology at the University of Bourdeaux.

If the wine tasters could discriminate odors independently of color, then you would expect them to apply the same odor descriptors (such as “floral” or “honey”) to the both wines. Instead, the researchers found that the tasters almost always used red wine odor descriptors (like “cherry” and “coal”) to refer to the red-colored wine – despite it being indistinguishable from the white in all respects other than color. This result demonstrates that cognitive expectations can dominate over smell when the two conflict.

Another study, performed in 2003 by Parr and colleagues, went further to demonstrate the automaticity of this effect. In their study, they gave two kinds of participants – wine experts and social drinkers – two versions of the same white wine, one kept white and one dyed red. As expected, non-experts (that is, social drinkers) were nearly indiscriminate in their judgments. With experts, however, even though they successfully differentiated dyed white wines from red wines, they could not prevent the red color from biasing their judgments. That is, their odor judgments on the red-colored white wines were more accurate when the wine was served in an opaque glass rather than a clear one.

When it comes to the man from the Costa Rica restaurant, this result offers two implications: on one hand, experts do indeed differ from novices in their ability to discriminate wines. On the other hand, neither expert nor novice could erase the effect of color on their odor perception, even when they were aware of it.

One can imagine generalizing the Morrot and Parr results to all kinds of food and beverages – would a lime-flavored purple drink taste of grape? Would a golden watermelon offer hints of pineapple? However, this kind of reasoning only applies to cases where the subject is deliberately manipulated – in real life, red wines are red and white wines are white. To further investigate the importance of imagination and context in wine tasting, we need to consider cases where the wine color is either normal or invisible.

In one such study, Goldstein and colleagues examined the correlation between wine price and subjective wine ratings across both novices and experts. In a series of 6000 blind tastings taken by 506 participants, they asked each person to rate each wine as “bad,” “okay,” “good”, or “great.” The prices per bottle ranged from $1.65 to $150. For non-experts, they found – shockingly – that price had a negative correlation with overall rating. That is, more expensive wines (when the price was unknown) were perceived to be worse than cheap ones. Meanwhile, for experts, they observed a non-negative (though not necessarily positive) correlation between price and quality. The researchers contrast these results, obtained from blind tests, with studies where the same kind of wine is presented as having a range of different prices. In those cases, the more expensive wine correlates positively with experienced pleasantness.

It seems, then, that for most people, more expensive wines technically taste worse, but are perceived to taste better by virtue of their price tag. Moreover, given how much the expert opinions diverged from the non-expert opinions, the wine ratings delivered by experts may have little to no relevance for the enjoyment of everyday people.

Price is not the only signal that can modify our experience of flavor. In a 2016 study of beers, Cravalho and colleagues played music found in previous studies to be associated with sourness, bitterness, and sweetness. They found that playing the selected soundtracks while participants drank beers resulted in significant changes to their ratings of sweetness, bitterness, sourness, and alcohol content. Thus, it seems that sound can also influence the taste of beverages.

Throughout these studies, two themes dominate: first, that cognitive effects like vision and price can override senses like smell and taste. Second, that experts and non-experts can differ drastically in their assessments. Although wine is one of the best-studied examples of these effects, they might also apply across all sorts of food and drinks, with important implications for food companies and marketers.

And what about that man I observed in Costa Rica? How much should we respect his judgment? On one hand, given the evidence that experts make different judgments than novices, one might have some respect for the man’s ability to judge the wine. On the other hand, even if he were indeed an expert, the man’s taste would likely not align with those of his guests, as most people are not socialized to appreciate such expensive tastes. Moreover, his real-life tasting would be influenced by everything from the color of the wine to the music playing in the restaurant to its price and its description – not to mention his own mood.

Perhaps the wine tasting – indeed, all tastings – are primarily theatres created for the designated tasters to bask in their own grandeur. Perhaps the man was not in fact a distinguished oenophile, and it wouldn’t even matter if he was, as long as he served his social function as the arbiter of refinement. Or maybe the man just didn’t like the wine.

References

Morrot, G., Brochet, F., & Dubourdieu, D. (2001). The color of odors. Brain and Language, 79(2), 309-320. https://doi.org/10.1006/brln.2001.2493

Wendy V. Parr , K. Geoffrey White & David A. Heatherbell (2003) The nose knows: influence of colour on perception of wine aroma, Journal of Wine Research, 14:2-3, 79-101, DOI: 10.1080/09571260410001677969

Goldstein R, Almenberg J, Dreber A, Emerson JW, Herschkowitsch A, Katz J. Do More Expensive Wines Taste Better? Evidence from a Large Sample of Blind Tastings. Journal of Wine Economics. 2008;3(1):1-9. doi:10.1017/S1931436100000523

Reinoso Carvalho, F., Wang, Q. (Janice), Van Ee, R., & Spence, C. (2016). The influence of soundscapes on the perception and evaluation of beers. Food Quality and Preference, 52, 32-41. https://doi.org/10.1016/j.foodqual.2016.03.009