Coffee is with tea and water in the top 3 most consumed drinks in the world.
Although a lot of good coffee lovers exist, not everyone likes the same coffee.
However, strangely, people more sensitive to caffeine and its bitter taste would consume more coffee, according to a study published November 15, 2018 in the journal Scientific Reports.
THE BITTER TASTE OF COFFEE
According to the results of the study, the more people are sensitive to the bitter taste of caffeine, the more they drink coffee.
Sensitivity based on genetics, bitterness is a natural alert system that protects us from harmful substances. So we should not like coffee.
Scientists say that people with increased ability to detect coffee bitterness learn to associate good things with it.
WHY DO WE LIKE THE COFFEE'S BIT TASTE?
Bitterness has evolved as a natural alert system to protect the body from harmful substances. By evolutionary logic, we should want to spit it out.
But it turns out that the more people are sensitive to the bitter taste of caffeine, the more they drink coffee. This sensitivity would be caused by a genetic variant.
"Logically we should expect that people particularly sensitive to the bitter taste of caffeine drink less," says the study. Yet, the results suggest that coffee consumers acquire a taste or ability to detect caffeine due to caffeine-induced positive (ie stimulation) reinforcement.
In other words, people who have an increased ability to taste the bitterness of coffee, and in particular the distinct bitter taste of caffeine, learn to associate positive things with it.
Note that in the population of this study, those who were more sensitive to caffeine and drinking a lot of coffee consumed little tea.
UNDERSTANDING THE TASTE OF A BIOLOGICAL POINT OF VIEW
The study also found that people sensitive to coffee were sensitive to the bitter taste of quinine and PROP.
Extracted from the bark of cinchona, quinine is a natural alkaloid antipyretic, analgesic and antimalarial. PROP (propylthiouracil or 6-N-Propylthiouracil) is a drug (antithyroid) and is also used in the genetic study of the perception of bitter taste in super-tasters - individuals who experience the flavors more intensely than the rest of the population.
In this study, for alcohol, greater sensitivity to PROP bitterness resulted in reduced alcohol consumption, especially red wine.
The results suggest that our perception of bitter tastes, based on our genetics, contributes to the preference for coffee, tea and alcohol.
For this study, scientists applied Mendelian randomization (a commonly used technique in disease epidemiology) to test the causal relationship between bitter taste and beverage consumption among more than 400,000 men and women in the UK.
The authors indicate that the genetic variants related to the perception of caffeine, quinine and PROP have already been identified through an earlier analysis. As part of the current study, these genetic variants were then tested to determine possible associations with coffee, tea and alcohol consumption.
Taste is a conscious representation associated with semantic, cultural and hedonic representations, but all of this "results from a specific activation through a population of sensory receptors and the activity of pathways and nerve centers".
Finally, the authors emphasize that "taste has been studied for a long time, but we do not know all the details. Taste is one of the senses we want to understand from a biological point of view.
SOURCES
- « Understanding the role of bitter taste perception in coffee, tea and alcohol consumption through Mendelian randomization. », Scientific Reports, 2018 ; https://www.nature.com/articles/s41598-018-34713-z, 8 (1) DOI: 10.1038/s41598-018-34713-z
- « Recalled taste intensity, liking and habitual intake of commonly consumed foods. », Appetite 109, 182–189 (2017).2.
- « Coffee and metabolic syndrome: A systematic review and meta-analysis. », Journal of Nutrition and Health 49, 213–222 (2016).