Recipe Mole Poblano
Do you think chocolate only belongs in sweet desserts? Then you haven't yet discovered the culinary world of Mole Poblano - the famous Mexican dish in which chocolate is the secret protagonist.
The tongue atlas
The tongue atlas is nonsense!
We explain why
Have you ever taken part in a wine tasting or other tasting event? Then it is unfortunately likely that you have been told about our human taste with a "tongue atlas". According to this theory, there are certain zones on the tongue that are responsible for sweet or bitter taste, for example. Sweetness should only be tasted at the tip of the tongue and bitterness only at the back of the tongue. Does that sound familiar? Too bad, because it's total nonsense and has been refuted for a very long time! Although disproved is the wrong word, because it was never actually true. If you follow the trail of the tongue atlas, you will often come across the name of a German researcher who published his study "Psychophysics of the Sense of Taste" in 1901, David P. Hänig. He was actually one of the first researchers to systematically investigate the perception of taste on our tongue. To do this, he applied various solutions to the tongue of colleagues at his institute: a sugar solution, a saline solution, hydrochloric acid and quinine. His result: people can perceive sweet, sour, salty and bitter on the entire top of their tongue! The tongue atlas is therefore not based on Hänig's findings, but unfortunately represents a serious misinterpretation, even today! Incidentally, you can read the 1901 study if you are interested in this topic in detail. You can find it, for example, at this link from the Max Planck Institute:
The taste zones
In the original study there are drawings of the tongue, similar to our picture here, which show that you perceive more at the edges of the tongue than in its center. But nothing in this study supports the theory of separate taste zones on the tongue. Hänig comes to the clear conclusion that all the flavors tested are equally perceptible at the edge of the tongue. This finding, which is over a hundred years old, is also supported by current research, except that it goes beyond Hänig's results in one respect. Hänig tested four flavors, the previously mentioned sweet, sour, salty and bitter. He did not yet know of another flavor, known as umami.
The flavors
Current research assumes that we can perceive at least five basic tastes on the tongue:
- Sweet: This flavor is triggered by sugar and sugary compounds. It often signals a source of energy and is pleasant.
- Sour: Sourness is caused by acidic compounds such as acids in fruits and vinegar. Sour indicates potentially inedible or spoiled food.
- Salty: Salty flavors are caused by sodium and other salts. Saltiness can indicate important minerals and electrolytes.
- Bitter: Bitterness is caused by various compounds often found in poisonous plants or inedible substances. It serves as a protective mechanism to prevent the consumption of potentially harmful substances.
- Umami: Umami is a savory or meaty taste caused by glutamate and certain nucleotides. This flavor is often present in protein-rich foods such as meat, fish, cheese and tomatoes.
Sounds complicated, but it is!
Research is still a long way from having fully decoded our human taste. Other possible flavors are being discussed and the interplay between the senses of taste and smell has not been clarified in every detail. Pungency is not a taste at all, it's about heat receptors... but that's way too much for today. Just this much, find out who won the Nobel Prize for Medicine in 2021 and what chilies have to do with it. Cutting-edge research in medicine, biology, psychology and chemistry is focusing on the topic of taste perception and is constantly finding out new things!
Perhaps this also explains the success of the tongue atlas, as it is so beautifully simple in comparison. But it is also very easy to refute. Point four states that bitterness is a warning of potentially harmful substances: Caution! Perhaps poisonous!
If you believe the tongue atlas, we are only warned of this danger at the very back of the mouth, just before swallowing. Warning, possibly poisonous! - oh... swallowed too late. We would probably have died out that way...
Our tongue - the all-rounder
Have you ever thought about why humans can stick out their tongues? Perhaps to be able to examine potentially dangerous food outside the body. In any case, it makes much more sense than the taste zone theory. For those interested! You can find a good summary of what we know about taste here, for example:
There are many more good videos, but unfortunately there are still many wrong ones! Of course, taste is most fun in practice. Perhaps a visit to the Chocolate Museum will convince you of how your taste works in our tastings.
P.S.: And if someone comes to you with the tongue atlas, send it to us too!
This post was written by:
Olaf Vortmann
My name is Olaf and I have been working for the Chocolate Museum since 2002. As a museum educator, I am responsible for our guided tours and tastings. That's very practical, because it's hard for me to imagine life without chocolate. But my annual consumption remains a secret!
