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When the sommelier comes to my table in the restaurant, I wonder whether they really are better at wine tasting than any of the guests. They make a surprising amount of money and they have to undergo very lengthy training. But are they really good or are they just good at pretending?
It has been known for a while that professional wine-tasters are sometimes bad at distinguishing red wine and white wine if they smell or taste them without having any information about the wine’s color (either because they are drinking it from black glasses or because the white wine is colored red with tasteless colorant). While the experiment that this conclusion is based on is often misreported, one can see how you can grab headlines with this. If wine experts can’t even tell red and white wine apart, what on earth do they have to pontificate about?
Even worse, some studies show that the bias from the perceived color is even stronger in wine experts than novices like you or me. If years of culinary schooling and wine tasting lead to more confusion, what’s the point?
A recent set of studies helps us to understand how these experiments that seem to show that wine experts are worse off than laypeople may be misleading. This study is about olfactory and gustatory mental imagery.
When you close your eyes and visualize an apple, this brings up visual mental imagery. It is seeing with the mind's eye. But mental imagery is also present in the other sense modalities. One example of auditory mental imagery is earworms, those little tunes that you keep hearing 'in the mind's ear' although you really don't want to.
And we also have mental imagery of smell and taste. When we see a photograph of a food item we like, this automatically triggers mental imagery of its smell (olfactory imagery) and mental imagery of its taste (gustatory imagery). I argued here that this explains the mind-boggling popularity of cooking shows.
Is the olfactory and gustatory mental imagery of wine experts better than ours? A recent study shows that it is, but only for wine-related stimuli. Novices have, on average, better visual mental imagery, but wine experts have better olfactory and gustatory imagery, but not for stimuli like roses or peanut butter, but only for wine-related smells and flavors.
This explains why wine experts bumble so badly sometimes. When they taste white wine that is colored red with odorless colorant, they form an expectation on the basis of what they see and form their olfactory and gustatory mental imagery on the basis of that as well. And given that their vision is tricked with the colorant, their olfactory and gustatory mental imagery is also tricked. And as they have more robust and more reliable olfactory and gustatory mental imagery, this leads them astray more.
In short, wine experts are not con artists. They are much better at tasting and smelling wine than you or I. But it is exactly this ability that makes it easier to fool them sometimes.
