Human taste sensory organs, called taste buds or gustatory calyculi, and concentrated on the upper surface of the tongue, appear to be receptive to relatively few chemical species as tastes. This contrasts markedly with the sense of olfaction, where very large numbers of different species can be differentiated. Taste is one of the most common and fundamental of the senses in life on Earth. ... Taste buds (or lingual papillae) are small structures on the upper surface of the tongue that provide information about the taste of food being eaten. ... Many animals have longer and more flexible tongues than humans. ... Olfaction, the sense of smell, is the detection of chemicals dissolved in air (or, by animals that breathe water, in water). ...

History

Five tastes are known to be sensed by taste buds: bitter, salty, sour, sweet, and umami. Until recently, most Western sources listed only the first four; in recent years, the fifth taste -- umami (savoriness) -- has become widely accepted. The most familiar example of an "umami" taste is that of the common food additive MSG. Monosodium glutamate, E 621 or Sodium Glutamate (IUPAC name- 2-Aminopentanedioic acid,2-Aminoglutaric acid,1-Aminopropane-1,3-dicarboxylic acid), commonly known as MSG, is a salt of sodium with glutamic acid. ...

In general, the sense of taste is often confused by smells that occur at the same time, and much of the everyday sensation of taste is derived from smell stimuli. Loss of the sense of smell (anosmia), for example when one has a cold, severely reduces one's sense of taste. Anosmia is the lack of olfaction, or a loss of the sense of smell. ...

Historically, the science of how humans sense taste has been full of misunderstandings. For many years, books on the physiology of human taste contained diagrams of the tongue showing levels of sensitivity to different tastes in different regions. There is no scientific foundation for these "maps", which were based on a misinterpretation of old research. Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ...

Umami was traditionally well recognized in many East Asian countries. Umami is often found in protein, some vegetables, and fermented foods, such as soy sauce, fish sauce, miso, and black bean sauce. Umami plays a particularly important role in Japanese foods: it is often extracted from fish, sea kelp, and/or shiitake mushrooms to create Japanese-style soup stock, commonly called "dashi", which is used in almost every Japanese dish.

Although umami was not as well recognized in Western countries until recently, many Western dishes benefit from including umami. For instance, soup stocks, anchovies, some cheeses, and tomato sauce/ketchup, all widely used, contain umami.

The ancient Chinese Five Elements philosophy lists slightly different five basic tastes: bitter, salty, sour, sweet, and hot instead of umami. In traditional Chinese philosophy, natural phenomena can be classified into the Five Elements (Chinese: 五行; pinyin: ): wood, fire, earth, metal, and water (木, 火, 土, 金, 水; mù, huǒ, tǔ, jīn, shǔi). ...

Saltiness

Saltiness is a taste produced by the presence of sodium chloride (and to a lesser degree other salts). The ions of salt, especially sodium (Na⁺) is detected by ions channels on the tongue, leading to action potential. Sodium chloride, also known as common salt, table salt, or halite, is a chemical compound with formula NaCl. ... In chemistry, salt is a general term used for ionic compounds composed of positively charged cations and negatively charged anions, so that the product is neutral and without a net charge. ... Schematic of an electrophysiological recording of an action potential showing the various phases which occur as the wave passes a point on a cell membrane. ...

Sourness

Sourness is the taste that detects acids. The mechanism for detecting sour taste is similar to that which detects salt taste. Hydrogen ion channels detect the concentration of protons (H⁺ ions) that have dissociated from an acid. An acid (often represented by the generic formula AH) is typically a water-soluble, sour-tasting chemical compound. ... Ion channels are present in the membranes that surround all biological cells. ...

Sweetness

Main article: Sweetness Sweetness is one of the five basic tastes, and is almost universally regarded as a pleasurable experience. ...

Sweetness is produced by the presence of sugars, some proteins and a few other substances. Sweetness is detected by a variety of G protein coupled receptors coupled to the G protein gustducin found on the taste buds. At least two different variants of the "sweetness receptors" need to be activated for the brain to register sweetness. The compounds which the brain senses as sweet are thus compounds that can bind with varying bond strength to several different sweetness receptors. The differences between the different sweetness receptors is mainly in the binding site of the G protein coupled receptors. And yet sour still has a sweet taste to some. A sugar is a form of carbohydrate used in the food and drinks industries, and important in biochemistry. ... In cell biology, G-protein-coupled receptors, also known as GPCR, seven transmembrane receptors, heptahelical receptors, or 7TM receptors, are a class of transmembrane receptors. ... G-proteins, short for guanine nucleotide binding proteins, are a family of proteins involved in second messenger cascades. ... Taste buds (or lingual papillae) are small structures on the upper surface of the tongue that provide information about the taste of food being eaten. ...

Binomial name Homo sapiens Linnaeus, 1758 Subspecies Homo sapiens idaltu (extinct) Homo sapiens sapiens Human beings define themselves in biological, social, and spiritual terms. ... The mole (symbol: mol) is one of the seven SI base units and is commonly used in chemistry. ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... Sucrose is the common chemical name for table sugar. ... Lactose is the sugar making up around 2-8% of the solids in milk. ... 1-propyl-2-amino-4-nitrobenzene is the strongest sweet-tasting substance known, about 5,000 the intensity of sucrose. ...

Bitterness

Bitterness, like sweetness, is sensed by G protein coupled receptors coupled to the G protein gustducin. Many people find bitter tastes to be unpleasant; many alkaloids taste bitter, and evolutionary biologists have suggested that a distaste for bitter things evolved to enable people to avoid poisoning. In cell biology, G-protein-coupled receptors, also known as GPCR, seven transmembrane receptors, heptahelical receptors, or 7TM receptors, are a class of transmembrane receptors. ... G-proteins, short for guanine nucleotide binding proteins, are a family of proteins involved in second messenger cascades. ... An alkaloid is a nitrogenous organic molecule that has a pharmacological effect on humans and other animals. ... Evolutionary biology is a subfield of biology concerned with the origin and descent of species, as well as their change over time, i. ...

The bitterest substance known is the synthetic chemical denatonium (e.g. under the trademark Bitrex [1] (http://www.bitrex.com/home.htm)), discovered in 1958. Denatonium benzoate is a white, odourless solid used as an aversive agent, i.e. an additive that prevents accidental ingestion of a toxic substance by humans, particularly children, and by animals. Denatonium, usually available as denatonium benzoate (e. ... 1958 was a common year starting on Wednesday of the Gregorian calendar. ...

The substance phenylthiocarbamide tastes very bitter to most people, but is virtually tasteless to others. This genetic variation in the ability to taste a substance has been a source of great interest to those who study genetics. Phenylthiocarbamide, also known as PTC, or phenylthiourea, is a synthetic organic molecule. ... Genetics (from the Greek genno γεννώ= give birth) is the science of genes, heredity, and the variation of organisms. ...

Umami

Savoriness or umami is the name for the taste sensation produced by the free glutamates commonly found in fermented and aged foods, for example parmesan and roquefort cheeses, as well as soy sauce and fish sauce. It is also found in significant amounts in various unfermented foods such as walnuts, grapes, broccoli, tomatoes, and mushrooms, and to a lesser degree in meat. The glutamate taste sensation is most intense in combination with sodium. This is one reason why tomatoes exhibit a stronger taste after adding salt. Sauces with umami and salty tastes are very popular for cooking, such as tomato sauces and ketchup for Western cuisines and soy sauce and fish sauce for East Asian and Southeast Asian cuisines. Glutamic acid or glutamate is one of the 20 most common natural amino acids. ... In its strictest sense, fermentation (formerly called zymnosis) is the energy-yielding anaerobic metabolic breakdown of a nutrient molecule, such as glucose, without net oxidation. ... Parmesan cheese. ... Roquefort can have one of several meanings: Roquefort cheese Roquefort, the mouse in Disneys The Aristocats Roquefort is the name or part of the name of several communes in France: Roquefort, in the Gers département Roquefort, in the Landes département Roquefort, in the Lot-et-Garonne département Roquefort-de... Cheese is a solid food made from the curdled milk of various animals—most commonly cows but sometimes goats, sheep, reindeer, and water buffalo. ... Soy sauce (US) or soya sauce (UK) is a fermented sauce, made from soybeans (soya beans), roasted grain, water and sea salt (US will use salt unless otherwise stated). ... Fish sauce is a condiment derived from fish that have been allowed to ferment. ... This article is about the walnut tree. ... Species Vitis acerifolia Vitis aestivalis Vitis amurensis Vitis arizonica Vitis x bourquina Vitis californica Vitis x champinii Vitis cinerea Vitis x doaniana Vitis girdiana Vitis labrusca Vitis x labruscana Vitis monticola Vitis mustangensis Vitis x novae-angliae Vitis palmata Vitis riparia Vitis rotundifolia Vitis rupestris Vitis shuttleworthii Vitis tiliifolia Vitis... Cultivar Group Brassica oleracea Italica Group Broccoli is a plant of the Cabbage family, Brassicaceae (formerly Cruciferae). ... Binomial name Solanum lycopersicum Linnaeus ref. ... Basidiocarps (mushrooms) of the fungus Leucocoprinus sp. ... Meat is animal tissue (mainly muscle) used as food. ... General Name, Symbol, Number sodium, Na, 11 Series alkali metal Group, Period, Block 1 (IA), 3, s Density, Hardness 968 kg/m3, 0. ... In chemistry, salt is a general term used for ionic compounds composed of positively charged cations and negatively charged anions, so that the product is neutral and without a net charge. ... Organic Ketchup, a 21st century condiment Ketchup (or catsup) is a popular condiment, usually made with ripened tomatoes. ... East Asia can be defined in either cultural or geographic terms. ... Location of Southeast Asia Southeast Asia is a subregion of Asia. ...

The additive monosodium glutamate (MSG), which was developed as a food additive in 1907 by Kikunae Ikeda, produces a strong umami taste. Umami is also provided by the nucleotides IMP (disodium 5’-inosine monophosphate) and GMP (disodium 5’-guanosine monophosphate). These are naturally present in many protein-rich foods. IMP is present in high concentrations in many foods, including dried Bonito flakes (Used to make Dashi, a Japanese broth). GMP is present in high concentration in dried Shiitake mushrooms, used in much of Asian cooking. There is a synergistic effect between MSG, IMP and GMP which together in certain ratios produce a strong umami taste. Monosodium glutamate, E 621 or Sodium Glutamate (IUPAC name- 2-Aminopentanedioic acid,2-Aminoglutaric acid,1-Aminopropane-1,3-dicarboxylic acid), commonly known as MSG, is a salt of sodium with glutamic acid. ... 1907 was a common year starting on Tuesday (see link for calendar). ... Kikunae Ikeda (池田 菊苗 Ikeda Kikunae, October 8, 1864 – May 3, 1936) was a Tokyo Imperial University professor who discovered the umami flavor. ... Disodium inosinate (E631) is a food additive often found in instant noodles, potato chips, and a variety of other snacks. ... Bonito is a name given to various species of medium-sized, predatory fish of the genus sarda, in the mackerel family, especially the common or Atlantic bonito (sarda sarda) and the Pacific bonito (sarda chiliensis). ... Dashi (出汁) is one of several simple soup stocks considered fundamental to Japanese cooking. ... Shiitake mushroom lentinus edodes (=lentinula edodes) Shiitake mushrooms (椎茸) are an edible mushroom typically cultivated on the shii tree (Pasania cuspidata--a relative of the oak). ...

Umami is considered basic in Japanese and Chinese cooking, but is not discussed as much in Western cuisine, where it is sometimes referred to as "savory", "meaty" or "moreish."

The name comes from umami (旨味 or うまみ), the Japanese name for the taste sensation. The characters literally mean "delicious flavour."

In English, the name of the taste is sometimes spelled umame, but umami (which conforms to the romanization standards of Japanese) is much more common, as in Society for Research on Umami Taste (http://www.srut.org/index_e.html). The English language is a West Germanic language that originates in England. ... A romanization or latinization is a system for representing a word or language with the Roman (Latin) alphabet, where the original word or language used a different writing system. ...

The same taste is referred to as xiānwèi (鮮味) in Chinese cooking.

A subset of umami taste buds responds specifically to glutamate in the same way that sweet ones respond to sugar. Glutamate binds to a variant of G protein coupled glutamate receptors. Glutamic acid or glutamate is one of the 20 most common natural amino acids. ... In cell biology, G-protein-coupled receptors, also known as GPCR, seven transmembrane receptors, heptahelical receptors, or 7TM receptors, are a class of transmembrane receptors. ...

References

• Kikunae Ikeda. (1909). New Seasonings. (see the site (http://chemse.oupjournals.org/cgi/content/full/27/9/847))
• Bernd Lindemann, Yoko Ogiwara, and Yuzo Ninomiya. (2002). The Discovery of Umami. (see the site (http://chemse.oupjournals.org/cgi/content/full/27/9/843))

External links

• Nature Neuroscience - Umami taste receptor identified (http://www.nature.com/neuro/press_release/nn0200.html)
• Receptor and Transduction Processes for Umami Taste (http://www.nutrition.org/cgi/content/full/130/4/942S)
• Researchers Define Molecular Basis of Human "Sweet Tooth" and Umami Taste (http://hum-molgen.org/NewsGen/11-2003/msg11.html)