Is Taste Nature or Nurture?

Do we love flavor because of biology or culture? Is good taste objective or subjective? Let’s talk it out.

I had the good sense to pull out my phone the first time we prepared watermelon for Suzy, my 8 month old daughter, to taste. It was one of the first “real foods” Suzy ate and was her very first fresh fruit. Here are the photos:

The instant joy on Suzy’s face when getting her first juicy, sweet taste of watermelon was thrilling, and it warms me still. There is no question that Suzy was born to love watermelon. It’s still her favorite fruit. It’s also her mother’s favorite. Watermelon season is a big deal around here. But that’s another story.

It’s clear that our sense of taste is closely tied to what nourishes us. Sweet foods are loaded with sugars, which are an important source of energy. We find nourishing fats and proteins delicious, and we even seem to have a taste for vitamins- the universal appeal of sour foods seems to be linked to our need for vitamin C. When sodium levels in our blood fall, a condition called hyponatremia, we crave salty food. Conversely, we instinctively reject bitter foods- an effective way to avoid certain poisons in berries and leaves. We are repulsed by the smells of rotten and putrid foods, not to mention excrement. Our likes and dislikes in taste and smell seem to be written onto our genes by the power of evolution. A baby like Suzy is born to love watermelon, just like her mom.

It doesn’t take much to move from this observation to the theory that there must be objective, ideal tastes. Though Plato never directly linked his theory of forms to the flavors of food (he considered taste a cruder sense than other modes of perception), plenty of others did; proposing the idea that there exist universal “good” tastes and they could be discovered through study, practice, and good genes. Flavor in food, the logic went, was like other kinds of aesthetic beauty: it comes from nature, it is discoverable by practice and observation, and it is ultimately objective. Emmanuel Kant, in his Critique of Aesthetic Judgement acknowledged that subjective perceptions existed, but that humanity has a kind of sensus communis, literally a ‘sense in commmon’, that represents a true, objective, discoverable kind of beauty. The European aristocracy embraced this idea, feeling that their aesthetics in art, fashion, and food must represent this universally true aesthetic. The idea of refined taste emerged in the 17^th century to distinguish elite tastes from the debased, crude tastes of the lower classes. And these tastes came from study and breeding, two obsessions of the European elite. The lower classes were not cultured enough to appreciate good tastes- they were too crude and, according to the aristocracy, inferior.

Elites enjoying cups of chocolate, Jean-Baptiste Charpentier the Elder, 1768

Except wait. We like sweetness a lot, but a spoonful of sugar in a glass of water is…. kind of gross. If our sense of sweetness was strictly objective and based on caloric value, wouldn’t that be the perfect drink? And what about bitter- children hate bitter foods, and many bitter foods are toxic. It’s clear we evolved to avoid bitterness and pungency- yet we pretty easily acquire a taste for bitter coffee and pungent flavors like chile and mustard. These tastes vary from person to person, and even more from culture to culture: Mexican, Thai, and Szechwan cuisines embrace spiciness in a way that is almost inedible to outsiders, and Italians celebrate bitterness in vegetables and cocktails as well as coffee. What’s delicious in one culture might be offensive in another- from the stinky tofu of Taiwan to the odorous époisses cheese of France to the peanut butter sandwiches of the United States. Liking of foods seems to be far from universal- not what you’d expect if taste was objective. This was noticed during the enlightenment: global exploration had already revealed that gastronomic tastes varied widely throughout the world- travelers’ stories were full of tales of exotic foods and strange flavors. Philosophers of the enlightenment struggled mightily with this: Hume got into the mix with Kant on the topic, and was much more open to the idea of individual variations on the aesthetic of taste. Neither could quite give up on the idea of absolutes, however, which led to the now famous paradox of taste: 1. if everyone can agree that the taste of sugar is “sweet”, and that sweet is good, then taste is objective. 2. If people like widely different flavors, and value them differently, then taste is subjective. 3. Statement one and two cannot both be true. Paradox! Over time, however, the subjectivists began to win the argument: it seemed like human variability of taste was just too great to be explained by error- and who was to say that entire cultures were wrong to celebrate certain flavors? Sociologist Pierre Bourdieu added his perspective via his work La Distinction: A Social Critique of the Value of Taste, in which he argued that defining “better” taste was just a way for elites to dominate the lower classes. Taste is taught, Bourdieu posited, not innate: it was a way for social class to be defined and enforced.

But then the scientists got involved. And they started to discover interesting things. For example, cilantro (aka coriander) leaf is known for being especially controversial among tasters: people love it or they hate it, and the haters say it tastes like soap. It turns out that this may be due to the action of a single heritable genetic variant. So if taste is heritable, what then? Well, not so fast: genetic variation can’t explain all of cilantro’s controversial reputation: culture seems to play a part too. Other research is even more tantalizing: it turns out that what a mother eats during her pregnancy has a strong effect on a child’s food preferences later in life- suggesting that some of our preferences may indeed be hardwired, though not through genetic inheritance, but because of prenatal exposure. So it’s become clear that preferences for flavor- like most human traits- are not cleanly the product of either biology or environment: they are affected by both.

The field of sensory science, for its part, had to find a resolution for the paradox of taste. Food science is practical, after all, and it needs to get on with the matter of understanding what people actually like and value in their foods. They solved the paradox in a very straightforward way: flavor perception was divided into two categories: descriptive- what a food tastes like, and affective- how much a person likes it. And descriptive taste is objective: a person tasting an apple blindfolded can either identify it correctly or not. It is either sweet or it is not, according to the presence or absence of sugar. However, whether the apple tastes good or not cannot be objective- it relies on a ‘subject’ to have an opinion about it, and is therefore subjective. I made a couple of cartoons to illustrate this concept, except with color instead of flavor. Both people can agree that the color is blue, even if they do not agree whether it is beautiful or not.

The same principle works for matters of taste in food and drink: people can agree on what it tastes like, without agreeing on whether it is delicious or not. For example, a fruity wine:

This works around the paradox of taste. It also helps with the nature/nurture question: a person can be more or less sensitive to (objective) perceptions of taste according to their genetics, but their subjective preferences are still true and valid. And though a person’s liking of particular flavors is influenced by evolution, it’s also personal, cultural, and, ultimately, beautifully, subjectively unique.

So, nature or nurture? Perception of flavor, and liking, are affected by both. Biology plays a role in our feelings about food, but culture has a powerful effect as well.