Taste in physiology is one of the types of chemoreception ; sensation arising from the action of various substances mainly on taste receptors (located on the taste buds of the tongue , as well as the posterior wall of the pharynx , soft palate , tonsil , epiglottis ).
Information from taste receptors is transmitted through the afferent fibers of the facial , glossopharyngeal, and vagus cranial nerves to the nucleus of the solitary tract of the medulla oblongata , then switching occurs in the nuclei of the thalamus and then to the postcentral gyrus and islet ( Latin insula ) of the cerebral cortex , where taste sensations form [1 ] . According to other sources, the cortical end of the taste system is located in the para-hippocampal gyrus ( lat. Gyrus parahippocampalis ) ( obsolete hooked gyrus , lat. Gyrus uncinatus ) and in the hippocampus ( lat. Hippocampus )   . In addition to the sweet , bitter , sour , salty taste, modern people in different countries also distinguish with their minds tart , burning , mint, alkaline, metallic and other tastes.
In humans, a sense of taste develops with the direct participation of the branches of the facial and glossopharyngeal nerves, which provide taste sensitivity in the anterior 2/3 and posterior 1/3 of the tongue, respectively.
- 1 Groups of taste receptors
- 2 History
- 3 Basic tastes
- 3.1 Sour
- 3.2 Sweet
- 3.3 Bitter
- 3.4 Salty
- 4 Umami
- 5 Other sensations close to taste
- 5.1 Hot taste
- 5.2 Tart
- 5.3 Bold
- 5.4 Metallic aftertaste
- 6 Taste Disorders - Dysgeusia
- 7 The concept of taste in the culture of different peoples
- 8 Notes
- 9 Literature
Taste receptor groups
Sweet and bitter substances usually cause only a sense of taste, while salty, sour ( pH <7) and alkaline (pH> 7 of some potent substances cause simultaneous damage to the mucous membranes and a painful sensation - burning, scratching, etc.
The actual taste sensations are usually mixed with tactile / tactile sensations (hence the sensations of astringent, astringent, sharp, burning) in the tongue. A huge role in the formation of taste (in its everyday understanding) is played by the olfactory sensations caused by the smell of volatile substances - LAV . We can say that the " aroma " of food consists of the simultaneous sensations of taste, smell, as well as thermal and tactile (through the trigeminal nerve ). The taste is perceived mainly by the root and upper surface of the back of the tongue, as well as its edges and tip.
Apparently, traditionally in European countries 4 “main tastes” were distinguished. In Dahl , for example, we find sayings that testify to the language mixture of the concepts of “bitter”, “tart”, “sour” in the 19th century.
In the XX century, in connection with the expansion of cultural exchange and the influence of people from Southeast Asia in Europe and America, they began to recognize taste as “minds” (sensation from sodium glutamate ). The recognition of this taste can be associated with the development of a network of Chinese restaurants that used products traditional for the countries of Southeast Asia, such as fermented soy or fish sauce , meat , etc., and later - synthetic monosodium glutamate, etc. (see. below).
However, in the East, 6 tastes have long been distinguished, including “hot”, which is understandable to our compatriots, who easily distinguish between bitter ( hin , bitter cucumber ) and “bitter” - hot pepper , radish , mustard .
Ancient Chinese philosophical model of the world - Five elements included 5 taste elements: bitter, salty, sour, sweet and hot.
In November 2005, French researchers showed that rats also distinguished “fatty” taste  .
The number of types of independent taste receptors is currently not precisely established. The 4 “main” tastes are the sociocultural archaism of European culture, the 5 main tastes are the culture of Southeast Asian states. Researchers at the University of Oregon have proposed a sixth-flavor, starchy flavor   .
It can be expected that the intensive development of modern science will soon determine the specific characteristics and mechanisms of the taste buds, and the number of recognized “basic” tastes will only increase. Note that in the terminology of professional tasters ( food , tea , coffee , wine ) the number of basic tastes used is much larger, but these terms in their majority refer to aroma rather than taste itself.
It is assumed that there are other types of receptors, for example receptors that respond to fatty acids , for example, linolenic acid .   
Sour taste is uniquely associated with the pH of the liquid. The mechanism of perception is similar to the perception of salt. Oxonium ions (mainly H 3 O + ) arise from acid dissociation . Since the pH value of human saliva is close to neutral (pH = 7), the action of strong acids and acids of medium strength causes a sensation of a purely acidic taste. However, some weak organic acids and hydrolyzed ions ( aluminum ) can also cause a sensation of astringency ( astringent taste ).
Sweetness is usually associated with the presence of sugars , but the same sensation arises from glycerin , some protein substances, amino acids. One of the chemical carriers of the "sweet" are hydroxo groups in large organic molecules - sugar , as well as polyols - sorbitol , xylitol . Sweet detectors - G-proteins located in the taste buds.
Bitterness, like sweetness, is perceived through G-proteins . Historically, the bitter taste has been associated with an unpleasant sensation, and possibly with the health hazard of certain plant products. Indeed, most plant alkaloids are simultaneously toxic and bitter, and evolutionary biology has reason for this conclusion.
- Substances with a characteristic very bitter taste: denatonium (Bitrex  , synthesized in 1958 ), phenylthiocarbamide (abbreviation "PTC"), quinine .
Its standard carrier is sodium chloride (sodium chloride is very close to this substance in composition) and potassium chloride. It is detected by the ion channel receptors in the tongue, changing the action potential . At the same time, the salty and sour tastes are strongly mixed, making it difficult to understand which of the factors is stronger.
The "fifth taste", traditionally used in Chinese culture, in other countries of the east. Umami - the name of the taste sensation produced by free amino acids, in particular glutamine , which can be found in fermented and seasoned foods, such as Parmesan and Roquefort cheeses, in soy and fish sauces. They are also found in a large number of unfermented foods, such as walnuts, grapes, broccoli, tomatoes, mushrooms and, to a lesser extent, in meat.
Other sensations similar to taste
The burning taste is not among the main tastes , as to date, the corresponding taste buds have not been found. It is associated with substances that stimulate “thermal” receptors ( ethanol , capsaicin ) - they excite the branches of the trigeminal nerve and contribute to the “pure taste” sensation.
This sensation (“ astringent taste ”) is associated with the reception of tannins ( tannins in tea, in thorns , etc.). The mechanism of its occurrence is explained by the binding of tannins to proteins rich in proline . 
A person undoubtedly perceives a “fatty” taste - but this sensation is not so clearly expressed as the standard tetrad “sweet - sour - bitter - salty” is usually distinguished.
A metallic taste is characteristic of fresh (non-coagulated) blood , and is also usually felt in food that comes in contact with oxidized metals (spoons, forks, jars). A particularly strong metallic taste is observed in contact with copper alloys - brass , cupronickel , etc., therefore, table objects made of cupronickel and nickel silver are covered with a thin layer of silver .
This sensation may be a sign of certain diseases; metal poisoning (for example, in casting fever ) or pesticides , the effects of certain drugs, for example metronidazole, etc.
A metallic taste in the mouth usually also occurs during an electrophoresis procedure.
Taste Disorders - Dysgeusia
Dysgeusia occurs for various reasons - pregnancy , diabetes mellitus , diseases of the gastrointestinal tract or oral cavity, anemia , hypothyroidism , etc.  .
Agevzia is distinguished - the loss of one of the main taste sensations , hypogevzia - the weakening of one of the sensations, parageusia , when salty is felt instead of sweet , and fantasygia (when a sensation of a particular taste is observed without obvious physical reasons, for example, with neurosis ).
A sense of taste can occur under the influence of radiation, in some cases at levels of about 1 R / h.
Disorders in the perception of taste in cooks is called bridility .
The concept of taste in the culture of different nations
- The expression “ They don’t argue about tastes (and colors ) ” (option: “ There is no companion for taste and color, ” jokes. “ All felt-tip pens are different in taste and color ”), known in many languages , illustrates people's fuzzy understanding of taste descriptions, and differences in assessment positivity in sensory perception among different people and ethnic groups , the meaninglessness of their absolute coordination.
- Purves. D. Neuroscience, 3rd ed. 2004
- Gaivoronsky I.V. Normal human anatomy. Textbook for honey. universities. - SPb., 2000
- Weight gain M.G., Lysenkov N.K., Bushkovich V.I. Human anatomy. - M., 1985
- BBC NEWS: Taste bud for fatty foods found
- Alexander Privalov. The sixth taste is open . Popular mechanics (September 2, 2016). Date of treatment February 6, 2017. Archived on February 6, 2017.
- Vladimir Korolev. Scientists have described the sixth taste of food . N + 1 (September 5, 2016). Date of treatment February 6, 2017. Archived on February 6, 2017.
- Fatty acid modulation of K + channels in taste receptor cells: gustatory cues for dietary fat
- Detection of free fatty acids following a conditioned taste aversion in rats
- Fat taste and lipid metabolism in humans
- Turbidity as a Measure of Salivary Protein Reactions with Astringent Substances - Horne et al. 27 (7): 653 - Chemical Senses
- (Deems, Doty and Settle 1991; Mott, Grushka and Sessle 1993)
- Tarkhanov I.R. Taste // Encyclopedic Dictionary of Brockhaus and Efron : in 86 volumes (82 volumes and 4 additional). - SPb. , 1890-1907.
- Khazdan E. V. “Pleasant Speech - Honeycomb Honey”, or Taste as Meaning // Traditional Culture. - 2017. - No. 4 (68). - S. 95-110.