Bitter differences? Chinese found to bear more tongue papillae than Danish, study finds
06 Jan 2021 --- Ethnicity may play a role in how sensitive a person is to bitter tastes, according to two studies from the University of Copenhagen in Denmark.
The research found differences between Chinese and Danish participants’ ability to taste bitter flavors and their preference for texture.
Tests revealed that the Chinese cohort was more sensitive to bitter tastes than the Danes, which was correlated to anatomical differences in these two groups’ tongue surfaces.
“We see a link between the prominence of bitter taste and the number of small bumps, known as papillae, on a person’s tongue,” says Professor Wender Bredie of the University of Copenhagen’s Department of Food Science (UCPH FOOD).
The analysis demonstrated that the Chinese test subjects generally had more of these papillae than the Danish subjects, which the researchers believe explains why Chinese people are better at tasting bitter flavors.
“It is relevant for Danish food producers exporting to Asia to know that Asian and Danish consumers probably experience tastes from the same product differently. This must be taken into account when developing products,” he adds.
Texture may be cultural
Bredie points out that genetics is only one of several factors that influence how we experience food. Another significant factor has to do with our preferences, including texture.
While the vast majority of Chinese subjects (77 percent) prefer foods that don’t require much chewing, the opposite holds true for the Danish subjects.
Among the Danes, 73 percent prefer eating foods with a harder consistency that require biting and chewing – rye bread and carrots, for example.
The reason for this difference remains unknown, but the researchers suspect that it stems from differences in food culture and how we learn to eat.
The studies do not point to tongue shape as making any difference.
In light of these findings, Bredie emphasizes that larger cohorts need to be examined before drawing conclusions between Danes and Chinese at the general population level.
PROP: The bitter standard
These new studies build upon previous insights that women are generally better than men at tasting bitter flavors, write the study authors.
The studies compared tasting abilities between 75 Danish and 77 Chinese study participants using the bitter substance 6-n-propylthiouracil (PROP), considered a genetic marker for differences in taste perception. 
Researchers used an AI algorithm to automate the counting of tongue papillae.
The two studies demonstrate that the Danish and Chinese groups experience this basic taste differently.
The results suggest other bitter flavors may be perceived differently, such as broccoli, brussels sprouts and dark chocolate.
The group further conducted research to accurately count the number of tasting papillae on the test subjects.
AI to measure taste
Using a new artificial intelligence method, researchers from UCPH FOOD, in collaboration with the UCPH’s Department of Computer Science, analyzed the number of mushroom-shaped “fungiform” papillae on the tongues of 152 test subjects, of whom half were Danish and half Chinese.
The new method automates the counting of tongue papillae – a job that was previously done manually – and delivers precision.
Using an algorithm, they have designed a tongue-coordinate system that can map papillae on individual tongues using image recognition.
Fungiform papillae, located at the tip of the tongue, are known to contain a large portion of our taste buds and play a central role in our food and taste experiences.
Differences in papillae distribution, size and quantity could therefore be significant across cultures and ethnicities.
Edited by Missy Green
