The human tongue is home to the taste buds, as you probably well know. And those taste buds help our brains to detect pleasant flavors and those flavors that may not be so pleasant. Of course, our interpretation of flavors helps us to know what would be beneficial to eat and what would be harmful. Bitterness, for example, evolved as one of our brain’s ways to detect things that might be harmful to the body if ingested.
So, why is that humans can sometimes enjoy things that are bitter?
Take coffee, for example. The coffee bean, on its own, is actually very bitter. And even after it is roasted and brewed, black coffee is not always “pleasant” on its own. And yet, coffee is the most popular, most widely-consumed beverage on the planet.
What is even more interesting, a new study indicates that the more sensitive a person is to bitter flavors, the more coffee they are likely to drink. Yes, it is counterintuitive but Northwestern University Feinberg School of Medicine assistant professor of preventive medicine, Marilyn Cornelis, comments that while we would expect the opposite to be true it seems that coffee consumers actually acquire a taste for or a develop an ability to detect caffeine. And that this “ability” likely comes out of a learned sense of positive enforcement: the stimulant nature of caffeine.
To put it plainly, the human brain can override its distaste for the bitterness of coffee because it provides a stimulant effect.
The study went on to also examine any relationship between fondness for other bitter flavors, like quinine and PROP, and coffee. PROP is a synthetic taste that you might relate to various compounds found in cruciferous vegetables (broccoli, cauliflower, etc). Those who are sensitive to those bitter flavors were actually found to choose aversion to coffee. Similarly, those with higher sensitivity to the bitterness found in PROP were also found to consume less alcohol.
Cornelis concludes, then, the findings suggest that our human perception of bitter taste is actually informed by our genetics and, thus, it is our genetic makeup, then, that might contribute to our penchant for coffee and tea or alcohol, etc.