Bitter
In addition to sweet , sour , salty and umami, bitter is one of the five flavors that z. B. can be perceived by the tongue .
On the other hand, a taste or smell is referred to as tart if it tastes or smells a little hot or spicy as well as slightly bitter or sour.
“ Bitter substances ” such as the alkaloid quinine in the soft drink bitter lemon are responsible for the bitter taste . The bitterest non- alkaline compound known is denatonium .
Reception in the human body
The bitter taste in humans is triggered by bitter substance receptors on the tongue : hTAS2 receptors ( hTAS2R ; the “h” at the beginning stands for “human”). hTAS2R receptors are located in the taste receptor cells , which in turn organize themselves into " taste buds ". These are located in the taste buds on the tongue. Most of the hTAS2R are located in the "wall papillae" at the base of the tongue.
There are around 25 different types of bitter receptors on the tips of the taste receptor cells in the mouth and throat . As before poisoning protect themselves by producing the part, for example, in the discharge of high bitter substance concentrations antimicrobial and digestive acting gastric boost. Five of these receptors respond to the caffeine contained in coffee or espresso , among other things .
Researchers from Potsdam and Vienna have shown that receptors in the stomach also react to bitter substances; they also influence the release of gastric acid.
In 2010, bitter substance receptors were detected in the muscle cells of the bronchi : If these receptors are stimulated by bitter substances (e.g. when consuming sage), the muscles relax and thereby expand the bronchi, which makes it easier to breathe in.
In 2016, scientists from the Skinitial research center at the University of Freiburg im Breisgau were able to detect bitter substance receptors on human skin: they strengthen the “skin barrier” that protects the body from solar radiation, bacterial attack or the penetration of toxins. Vegetable bitter substances such as amarogentin from the yellow gentian or salicin from the willow dock here and cause calcium to flow into the skin cells . After the treatment with amarogentin and salicin, the fat content in the upper layer of the skin had increased.
In addition, it has been observed that the bitter substance diphenidol stimulates nerve cells to form dendrites : These serve to pass on information to neighboring cells (a process that corresponds to normal learning).
Bitter substances in dishes
Finely dosed, the bitter taste can give food and drinks a "certain something". Examples of this (which also have the word bitter in their designation) are z. B. bitter almond , bitter lemon , bitter orange or dark chocolate . In higher concentrations, the content of bitter substances can also make supposed foods inedible, as is the case with the bitter boletus fungus ; originally as a medical tonic developed Angostura bitters is so bitter that it is suitable only as a seasoning or flavoring ingredient.
The bitter substance receptors in the stomach, which influence the secretion of gastric acid, explain the appetite-stimulating and digestive effects of espresso or other foods containing bitter substances, such as fruit (e.g. oranges , lemons ), vegetables , herbs , salads , " bitters " or that in beer contained hops .
See also
Web links
- Bild der Wissenschaft , February 7, 2005, Ilka Lehnen-Beyel, Wissenschaft.de - Bitter disposition ( Memento from November 20, 2005 in the Internet Archive )
Individual evidence
- ↑ a b c SecurVita BKK Newsletter 01 | 2018, Nutrition: Small accelerators
- ↑ a b c badische-zeitung.de , June 9, 2016: How bitter substances can help you think (July 22, 2016)
