For a long time, people have generally accepted a limited number of "basic tastes", all of which can be summarized as the following. Until 2000, it was considered as a set of four basic flavors. The fifth flavor, umami, was added by the work of many authorities in this field.

bitter taste

Bitter taste is unpleasant, sharp or unpleasant to many people. Common painful foods and drinks include coffee, unsweetened chocolate, bitter gourd, beer, uncured olives, orange peel, many plants, dandelion green party and escarole in Cruciferae. Quinine is also famous for its bitter taste and exists in quinine water. The most painful substance is called synthetic chemical denatonium. It is used as a preservative and added to toxic substances to prevent accidental swallowing. This was discovered by 1958 when MacFarlane Smith in Edinburgh, Scotland studied lidocaine, a local anesthetic.

Studies have shown that tas2r (taste receptor, type 2), such as tas2r38, is a bitter-sensitive substance for its ability to bind to the head of G protein. They found that not only did they have the ability to taste some "bitter" ligands, but also the form of the receptor itself (surface constraints, monomers). Researchers use two synthetic substances, phenylthiourea (PTC) and 6- n-propyl (all rights reserved) to study the painful viewpoint of genetics. Some people are sensitive to the bitterness of these two substances, but others are actually tasteless. Among them, taste is sensitive, and some are so-called "super tasters" whose PTC and props are very painful. The ability of this genetic variation to taste substances has always been a source of great interest to those who study genetics. In addition, PTC's delicious taste is related to its ability to taste many natural bitter compounds, and many of them are known to be toxic, so it is interested in people who study its evolution.

salty taste

Salty taste is composed of a taste, mainly due to the existence of sodium ions. The alkali metal groups of other ions are too salty. But further away from less sodium, it is a salty feeling. Lithium and potassium ions are most similar in size to sodium ions, so the salty taste is also the most similar. On the contrary, rubidium and cesium ions are much larger, so the salty taste is different, so. Potassium, potassium chloride-potassium chloride, is the main component of substitute salt.

Other monovalent cations, such as ammonium, ammonium ions and divalent cations in the periodic table of alkaline earth metals, such as calcium, usually cause pain rather than salty taste, although they can generate action potentials through the tongue directly passing through ion channels.

sour flavour

Look at the acid. The acid is redirected here. For other purposes, see acid (disambiguation)

Sour taste is a test of acidity. The mechanism detects that the taste of acid is similar, that is, the taste of salt is detected. The hydrogen ion channel detects the concentration of ions (h3o+ ions) formed by acid and water.

Hydrogen ions can penetrate the sensitive channel of amiloride, but this is not the only mechanism to detect the quality of sour taste. Other approaches have been proposed in the literature. Hydrogen ions also inhibit potassium channels, which usually act as hyperpolarized cells. By combining the direct uptake of hydrogen ions (i.e. the depolarization of the cell itself) and the inhibition of hyperpolarization channels, sour taste leads to the activation of taste cells in this specific way. In addition, it has also been suggested that weak acids, such as CO2, are converted into bicarbonate ion hco3 _ 3 under the action of carbonic anhydrase.

fresh flavour

Main article: umami

Umami is the name of taste. Compounds produced by feeling, such as glutamic acid, are commonly found in fermented and aged foods. In English, this is sometimes called "meat" or "salty taste". The word "ぅまみ" literally means "delicious". Umami is a word commonly used by taste scientists in the semester. The same taste is called xiānwèi (umami or umami) in Chinese food. Umami is considered as a basic taste in China and Japanese cooking, but it is not discussed much in western cooking.

sweet taste

Main article: sweet

Sweetness is caused by sugar, protein and other substances. Sweetness is often associated with aldehydes and ketones containing carbonyl groups. Sweetness is detected by detecting G-protein gustatory coupled with various G-protein coupled receptors, which exist in taste buds. At least two different varieties of "sweetness receptors" need to be activated as the sweetness registered by the brain. The brain senses sweet compounds, so compounds can bind to two different sweet receptors with different binding strengths. These receptors T 1R2tri (heterodimer) and t 1r2 (homodimer) have been proved to be necessary for all sweet remote sensing in humans and animals.

Humans have evolved taste receptors to detect amino acids such as glutamic acid. Amino acids are usually found in meat, cheese, fish and other foods rich in protein. For example, food contains glutamic acid (so it has a strong flavor), such as beef, mutton, parmesan cheese and goat cheese, as well as soy sauce and fish sauce. The taste of glutamic acid is strongest in the combination of sodium ions and is found in salt. Sauce and salty taste are very popular cooking, such as western food with soy sauce in Hust County and soy sauce and fish sauce are Asian cuisines.

The additive monosodium glutamate (MSG), which was developed as a food additive by Kikumiao Ikeda in 1907, produced a strong flavor. Umami taste is also provided by nucleotides 5'- inosine monophosphate (input and output) and 5'- guanosine (GMP). These naturally exist in many foods rich in protein. Import and export are highly concentrated, and many foods, including dried bonito slices, are used to make big stones and Japanese broth. GMP is used in dried mushrooms in high concentration in most Asian dishes. There is a synergistic effect among monosodium glutamate, import and export, and GMP, and they produce a strong umami flavor in a certain proportion.

Some umami taste buds have the same reaction to glutamic acid as to sweet reactive sugar. A variant of glutamate binding, G protein is coupled to glutamate receptor.