Bitter truth? Coffee drinkers have a higher sensitivity to its bitter taste, study suggests

20 Nov 2018 --- According to a new study from Northwestern Medicine and QIMR Berghofer Medical Research Institute in Australia, the more sensitive you are to the bitter taste in coffee, the more coffee you are likely to drink. 

Using Mendelian randomization, a technique commonly used in disease epidemiology, researchers tested the causal relationship between bitter taste and beverage consumption in more than 400,000 men and women in the UK. 

A previous study on Australian twins allowed for data on the genetic variants linked to caffeine, quinine and PROP perception to be identified through genome-wide analysis of solution taste-ratings. These genetic variants were then tested for associations with self-reported consumption of coffee, tea and alcohol in the current study.

The group of researchers discovered that due to a genetic variant, the more coffee people consumed, the more they could detect the bitter taste in it. Positively associating it with a caffeine jolt, they were conditioned to crave more of it, the researchers point out.

“You'd expect that people who are particularly sensitive to the bitter taste of caffeine would drink less coffee. The opposite results of our study suggest coffee consumers acquire a taste or an ability to detect caffeine due to the learned positive reinforcement (i.e., stimulation) elicited by caffeine,” says Assistant Professor of Preventive Medicine at Northwestern University Feinberg School of Medicine, Marilyn Cornelis. 

Additionally, the study found that people who avoid coffee and red wine are sensitive to the bitter flavors of quinine and PROP, a synthetic taste linked to the compounds in cruciferous vegetables. 

Cornelis says: “The findings suggest our perception of bitter tastes, informed by our genetics, contributes to the preference for coffee, tea and alcohol.”

“Taste has been studied for a long time, but we don't know the full mechanics of it. Taste is one of the senses and we want to understand it fully from a biological standpoint,” she adds. 

According to data from Innova Market Insights, coffee is clearly trending among Millennial and Generation Z consumers. Tapping into the taste and experiential associations of coffee and the health benefits of tea, we often see their application as ingredients and flavors frequently featuring across categories ranging from energy bars to yogurt and even jam.