The Truth About Your Taste Buds
Since grade school we’ve been taught that our taste buds work according to this diagram:
1.bitter, 2.sour, 3.salty, 4.sweet
This map has led many people to believe that there are 4 specific types of tastebuds on the perimeter of the mouth representing bitter, sour, salty and sweet.
Yet scientific research has proven the tongue map a myth.
In reality, the receptors for tastes are spread somewhat evenly across the tongue. A fifth taste is also present. Known as umami, the fifth taste is a Japanese word that loosely translates as “meaty” or “savory”, a sensation elicited by glutamine.
Early Scientific Research and the Creation of the Tongue Map
In 1901 German scientist Herr Hanig published his PhD thesis in Philosophische Studien where he used a diagram to summarize his study on the distribution of the four taste sensitivities around the outer edge of the tongue.
While taste sensitivities were noted, they were incredibly minor.
Then in 1942, a researcher by the name of Edwin Boring wrote Sensation and Perception in the History of Experimental Psychology.
Boring took Hanig’s raw data and calculated real numbers for sensitivity levels. These numbers were then plotted on a graph in such a way that lead other scientists to conclude that where sensitivity to a specific taste was minimal, the taste was therefore absent altogether.
From here, the infamous tongue map was created and began popping up in grade school textbooks (and wine education). The map has since led people to believe that sweet, sour, salty and bitter can only be tasted in their respective region on the tongue.
How ‘the Map’ Became ‘the Myth’
Researcher Virginia Collings in 1974 published a study in Attention, Perception and Psychophysics that reexamined Hanig’s data.
She agreed with his main finding that slight sensitivity variations do exist around the tongue, but that these variations were too small to bear any significance.
Collings found that all tastes can be detected anywhere there are taste receptors. These areas include the tongue, the soft palate at the back roof of the mouth, and even the epiglottis.
As well, a study published by David V. Smith and Robert F. Margolskee in Scientific America stated:
“In reality, all qualities of taste can be elicited from all regions of the tongue that contain taste buds. At present, we have no evidence that any kind of spatial segregation of sensitivities contributes to the neural representation of taste quality, although there are some slight differences in sensitivity across the tongue and palate, especially in rodents.”
How We Actually Taste
Scientists now believe that all our taste buds experience bitter, salty, sweet, sour and umami. Enzymes in your saliva break down food into chemicals which then come in contact with your taste buds, setting off a host of different reactions.
These reactions then travel along nerve fibers to your nose. Where the palate can detect just five basic tastes, the nose can discriminate many thousands of odors. And that’s where the real fun begins, particularly for wine lovers!
References
The Science of Wine, From Vine to Glass
True or False: Different Parts of the Tongue Sense Different Tastes by Krisha McCoy, MS
Scientific America: Secrets of the Senses by David V. Smith and Robert F. Margolskee
Live Science: The Tongue Map: Tasteless Myth Debunked by Christopher Wanjek
Images
‘Tongue Map’ courtesy of Wikipedia
‘Bogus Map’ courtesy of Denver Museum of Nature and Science
