taste.doc

32
Taste From Wikipedia, the free encyclopedia Jump to: navigation , search This article is about the sense. For the social and aesthetic aspects of "taste", see Taste (sociology) . For other uses, see Taste (disambiguation) . Taste bud Taste, gustatory perception, or gustation [1] is one of the five traditional senses . Taste is the sensation produced when a substance in the mouth reacts chemically with receptors of taste buds. Taste, along with smell (olfaction ) and trigeminal nerve stimulation (which also handles touch for texture, also pain, and temperature), determines flavors , the sensory impressions of food or other substances. Humans perceive taste through sensory organs called taste buds , [2] or gustatory calyculi, concentrated on the top of the tongue . [3] The tongue is covered with thousands of small bumps called papillae, which are easily visible to the naked eye. Within each papilla are hundreds of taste buds, the organ of taste transduction. [4] There are between 2000 and 5000 [5] taste buds that are located on the back and front of the tongue. Others are located on the roof, sides and back of the mouth, and in the throat. Each taste bud contains 50 to 100 taste receptor cells. Taste perception fades with

Upload: ayaz-saair

Post on 26-Oct-2015

19 views

Category:

Documents


0 download

DESCRIPTION

dgdfgfdgf

TRANSCRIPT

Page 1: Taste.doc

TasteFrom Wikipedia, the free encyclopediaJump to: navigation, search This article is about the sense. For the social and aesthetic aspects of "taste", see Taste (sociology). For other uses, see Taste (disambiguation).

Taste bud

Taste, gustatory perception, or gustation[1] is one of the five traditional senses. Taste is the sensation produced when a substance in the mouth reacts chemically with receptors of taste buds. Taste, along with smell (olfaction) and trigeminal nerve stimulation (which also handles touch for texture, also pain, and temperature), determines flavors, the sensory impressions of food or other substances.

Humans perceive taste through sensory organs called taste buds,[2] or gustatory calyculi, concentrated on the top of the tongue.[3] The tongue is covered with thousands of small bumps called papillae, which are easily visible to the naked eye. Within each papilla are hundreds of taste buds, the organ of taste transduction.[4] There are between 2000 and 5000[5] taste buds that are located on the back and front of the tongue. Others are located on the roof, sides and back of the mouth, and in the throat. Each taste bud contains 50 to 100 taste receptor cells. Taste perception fades with age: On average, people lose half their taste receptors by time they turn 20.[4]

The sensation of taste can be categorized into five basic tastes: sweetness, sourness, saltiness, bitterness, and umami. Taste buds are able to differentiate among different tastes through detecting interaction with different molecules or ions. Sweet, umami, and bitter tastes are triggered by the binding of molecules to G protein-coupled receptors on the cell membranes of taste buds. Saltiness and sourness are perceived when alkali metal or hydrogen ions enter taste buds, respectively.[6] As taste senses both harmful and beneficial things, all basic tastes are classified as either aversive or appetitive, depending upon the effect the things they sense have on our bodies.[7] Sweetness helps to identify energy-rich foods, while bitterness serves as a warning sign of poisons.[8]

Page 2: Taste.doc

The basic tastes contribute only partially to the sensation and flavor of food in the mouth — other factors include smell,[2] detected by the olfactory epithelium of the nose;[9] texture,[10] detected through a variety of mechanoreceptors, muscle nerves, etc.;[11] temperature, detected by thermoreceptors; and "coolness" (such as of menthol) and "hotness" (pungency), through chemesthesis.

Contents

1 Introduction o 1.1 History o 1.2 Recent discoveries

2 Basic tastes o 2.1 Sweetness o 2.2 Sourness o 2.3 Saltiness o 2.4 Bitterness o 2.5 Umami

3 Measuring relative tastes 4 Functional structure 5 Further sensations 6 Other concepts

o 6.1 Supertasters o 6.2 Aftertaste o 6.3 Acquired taste o 6.4 Innervation o 6.5 Disorders of taste

7 See also 8 Notes

o 8.1 Footnotes o 8.2 Citations

9 Further reading 10 External links

Introduction

History

In the West, Aristotle, who postulated c. 350 BCE [12] that the two most basic tastes were sweet and bitter,[13] was one of the first to develop a list of basic tastes.[14]

Ayurveda, an ancient Indian healing science, has its own tradition of basic tastes, comprising sweet, salty, sour, pungent, bitter & astringent.[15]

The Ancient Chinese and Indians have also commonly regarded Spiciness as a basic taste, although not included in this article.

Page 3: Taste.doc

Recent discoveries

The receptors for the basic tastes of bitter, sweet and umami have been identified. They are G protein-coupled receptors.[16] The cells that detect sour have been identified as a subpopulation that express the protein PKD2L1. The responses are mediated by an influx of protons into the cells but the receptor for sour is still unknown . The receptor for amiloride-sensitive attractive salty taste in mice has been shown to be a sodium channel.[17] There is some evidence for a sixth taste that senses fatty substances.[18]

Basic tastes

For a long period, it was commonly accepted[who?] that there is a finite and small number of "basic tastes" of which all seemingly complex tastes are ultimately composed. Just as with primary colors, the "basic" quality of those sensations derives chiefly from the nature of human perception, in this case the different sorts of tastes the human tongue can identify. As of the early twentieth century, physiologists and psychologists believed there were four basic tastes: sweetness, sourness, saltiness, bitterness. At that time umami was not proposed as a fifth taste[19] but now a large number of authorities recognize it as the fifth taste.[citation needed] In Asian countries within the sphere of mainly Chinese and Indian cultural influence, pungency (piquancy or hotness) had traditionally been considered a sixth basic taste.[citation needed]

Sweetness

Main article: SweetnessSee also: Miraculin and Curculin

Sweetness, usually regarded as a pleasurable sensation, is produced by the presence of sugars and a few other substances. Sweetness is often connected to aldehydes and ketones, which contain a carbonyl group. 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" must be activated for the brain to register sweetness. Compounds the brain senses as sweet are thus compounds that can bind with varying bond strength to two different sweetness receptors. These receptors are T1R2+3 (heterodimer) and T1R3 (homodimer), which account for all sweet sensing in humans and animals.[20] Taste detection thresholds for sweet substances are rated relative to sucrose, which has an index of 1.[21][22] The average human detection threshold for sucrose is 10 millimoles per liter. For lactose it is 30 millimoles per liter, with a sweetness index of 0.3,[21] and 5-Nitro-2-propoxyaniline 0.002 millimoles per liter.

Sourness

"Sour" redirects here. For other uses, see Sour (disambiguation).

Look up sour in Wiktionary, the free dictionary.

Page 4: Taste.doc

Sourness is the taste that detects acidity. The sourness of substances is rated relative to dilute hydrochloric acid, which has a sourness index of 1. By comparison, tartaric acid has a sourness index of 0.7, citric acid an index of 0.46, and carbonic acid an index of 0.06.[21][22]

Sour taste is detected by a small subset of cells that are distributed across all taste buds in the tongue. Sour taste cells can be identified by expression of the protein PKD2L1,[23]although this gene is not required for sour responses. There is evidence that the protons that are abundant in sour substances can directly enter the sour taste cells. This transfer of positive charge into the cell can itself trigger an electrical response. It has also been proposed that weak acids such as acetic acid, which are not fully dissociated at physiological pH values, can penetrate taste cells and thereby elicit an electrical response. According to this mechanism, intracellular hydrogen ions inhibit potassium channels, which normally function to hyperpolarize the cell. By a combination of direct intake of hydrogen ions (which itself depolarizes the cell) and the inhibition of the hyperpolarizing channel, sourness causes the taste cell to fire action potentials and release neurotransmitter. The mechanism by which animals detect sour is still not completely understood.

The most common food group that contains naturally sour foods is fruit, such as lemon, grape, orange, tamarind, and sometimes melon. Wine also usually has a sour tinge to its flavor, and if not kept correctly, milk can spoil and develop a sour taste. Children show a greater enjoyment of sour flavors than adults,[24] and sour candy is popular in North America[25] including Cry Babies, Warheads, Lemon drops, Shock Tarts and sour versions of Skittles and Starburst. Many of these candies contain citric acid.

Saltiness

Saltiness is a taste produced primarily by the presence of sodium ions. Other ions of the alkali metals group also taste salty, but the further from sodium the less salty the sensation is. The size of lithium and potassium ions most closely resemble those of sodium and thus the saltiness is most similar. In contrast rubidium and cesium ions are far larger so their salty taste differs accordingly.[citation needed] The saltiness of substances is rated relative to sodium chloride (NaCl), which has an index of 1.[21][22] Potassium, as potassium chloride - KCl, is the principal ingredient in salt substitutes, and has a saltiness index of 0.6.[21][22]

Other monovalent cations, e.g. ammonium, NH4+, and divalent cations of the alkali earth

metal group of the periodic table, e.g. calcium, Ca2+, ions generally elicit a bitter rather than a salty taste even though they, too, can pass directly through ion channels in the tongue, generating an action potential.

Bitterness

Bitterness is the most sensitive of the tastes, and many perceive it as unpleasant, sharp, or disagreeable, but it is sometimes desirable and intentionally added via various bittering

Page 5: Taste.doc

agents. Common bitter foods and beverages include coffee, unsweetened cocoa, South American mate, bitter gourd, beer (due to hops), bitters, olives, citrus peel, many plants in the Brassicaceae family, dandelion greens, wild chicory, and escarole. Quinine is also known for its bitter taste and is found in tonic water.

Bitterness is of interest to those who study evolution, as well as various health researchers[21][26] since a large number of natural bitter compounds are known to be toxic. The ability to detect bitter-tasting, toxic compounds at low thresholds is considered to provide an important protective function.[21][26][27] Plant leaves often contain toxic compounds, yet even amongst leaf-eating primates, there is a tendency to prefer immature leaves, which tend to be higher in protein and lower in fiber and poisons than mature leaves.[28] Amongst humans, various food processing techniques are used worldwide to detoxify otherwise inedible foods and make them palatable.[29]

The threshold for stimulation of bitter taste by quinine averages a concentration of 0.000008 M.[21] The taste thresholds of other bitter substances are rated relative to quinine, which is thus given a reference index of 1.[21][22] For example, Brucine has an index of 11, is thus perceived as intensely more bitter than quinine, and is detected at a much lower solution threshold.[21] The most bitter substance known is the synthetic chemical denatonium, which has an index of 1,000.[22] It is used as an aversive agent (a bitterant) that is added to toxic substances to prevent accidental ingestion. This was discovered in 1958 during research on lignocaine, a local anesthetic, by MacFarlan Smith of Gorgie, Edinburgh, Scotland.

Research has shown that TAS2Rs (taste receptors, type 2, also known as T2Rs) such as TAS2R38 coupled to the G protein gustducin are responsible for the human ability to taste bitter substances.[30] They are identified not only by their ability to taste for certain "bitter" ligands, but also by the morphology of the receptor itself (surface bound, monomeric).[31] The TAS2R family in humans is thought to comprise about 25 different taste receptors, some of which can recognize a wide variety of bitter-tasting compounds.[32] Over 550 bitter-tasting compounds have been identified, of which about 100 have been assigned to one or more specific receptors.[33] Recently it is speculated that the selective constraints on the TAS2R family have been weakened due to the relatively high rate of mutation and pseudogenization.[34] Researchers use two synthetic substances, phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) to study the genetics of bitter perception. These two substances taste bitter to some people, but are virtually tasteless to others. Among the tasters, some are so-called "supertasters" to whom PTC and PROP are extremely bitter. The variation in sensitivity is determined by two common alleles at the TAS2R38 locus.[35] This genetic variation in the ability to taste a substance has been a source of great interest to those who study genetics.

Umami

Main article: Umami

Page 6: Taste.doc

Umami is an appetitive taste[7] and is described as a savory[36][37] or meaty [37] [38] taste. It can be tasted in cheese [39] and soy sauce,[40] and while also found in many other fermented and aged foods, this taste is also present in tomatoes, grains, and beans.[39] Monosodium glutamate (MSG), developed as a food additive in 1908 by Kikunae Ikeda,[41] produces a strong umami taste.[40] See TAS1R1 and TAS1R3 pages for a further explanation of the amino-acid taste receptor. A loanword from Japanese meaning "good flavor" or "good taste",[42] umami (旨味?) is considered fundamental to many Eastern cuisines[43] and was first described in 1908,[44] although it was only recently recognized in the West as a basic taste.[40][45]

Some umami taste buds respond specifically to glutamate in the same way that "sweet" ones respond to sugar. Glutamate binds to a variant of G protein coupled glutamate receptors.[46][47]

Measuring relative tastes

Measuring the degree to which a substance presents one basic taste can be achieved in a subjective way by comparing its taste to a reference substance.

Sweetness is subjectively measured by comparing the threshold values, or level at which the presence of a dilute substance can be detected by a human taster, of different sweet substances.[48] Substances are usually measured relative to sucrose,[49] which is usually given an arbitrary index of 1[50][51] or 100.[52] Fructose is about 1.4 times sweeter than sucrose; glucose, a sugar found in honey and vegetables, is about three-quarters as sweet; and lactose, a milk sugar, is one-half as sweet.[b][48]

The sourness of a substance can be rated by comparing it to very dilute hydrochloric acid (HCl).[53]

Relative saltiness can be rated by comparison to a dilute salt solution.[54]

Quinine, a bitter medicinal found in tonic water, can be used to subjectively rate the bitterness of a substance.[55] Units of dilute quinine hydrochloride (1 g in 2000 mL of water) can be used to measure the threshold bitterness concentration, the level at which the presence of a dilute bitter substance can be detected by a human taster, of other compounds.[55] More formal chemical analysis, while possible, is difficult.[55]

Functional structure

Main article: Gustatory systemSweetness

Sweetness is produced by the presence of sugars, some proteins, and a few other substances.[citation needed] It is often connected to aldehydes and ketones, which contain a carbonyl group.[citation needed]Sweetness is detected by a variety of G protein-coupled

Page 7: Taste.doc

receptors coupled to a G protein that acts as an intermediary in the communication between taste bud and brain, gustducin.[56] These receptors are T1R2+3 (heterodimer) and T1R3 (homodimer), which account for sweet sensing in humans and other animals.[57]

Sourness

Sourness is acidity,[58][59] and, like salt, it is a taste sensed using ion channels.[60] Hydrogen ion channels detect the concentration of hydronium ions that are formed from acids and water.[citation needed] In addition, the taste receptor PKD2L1 has been found to be involved in tasting sour.[61]

Saltiness

Saltiness is a taste produced best by the presence of cations (such as Na+

, K+

or Li+)[60] and, like sour, it is tasted using ion channels.[60]

Other ions of the alkali metals group also taste salty, but the less sodium-like the ion is, the less salty the sensation.[citation needed] As the size of lithium and potassium ions is close to that of sodium, they taste similar to salt.[citation needed] In contrast, the larger rubidium and cesium ions do not taste as salty.[citation needed]

Other monovalent cations, e.g., ammonium, NH+

4, and divalent cations of the alkali earth metal group of the periodic table, e.g., calcium, Ca2+

, ions, in general, elicit a bitter rather than a salty taste even though they, too, can pass directly through ion channels in the tongue.[citation needed]

Bitterness

Research has shown that TAS2Rs (taste receptors, type 2, also known as T2Rs) such as TAS2R38 are responsible for the human ability to taste bitter substances.[62] They are identified not only by their ability to taste certain bitter ligands, but also by the morphology of the receptor itself (surface bound, monomeric).[63]

Umami

The amino acid glutamic acid is responsible for umami,[64][65] but some nucleotides (inosinic acid [43] [66] and guanylic acid [64] ) can act as complements, enhancing the taste.[43]

[66]

Glutamic acid binds to a variant of the G protein-coupled receptor, producing an umami taste.[67][68]

Further sensations

Page 8: Taste.doc

The tongue can also feel other sensations not generally included in the basic tastes. These are largely detected by the somatosensory system.

Pungency (also Spicyness or Hotness)Main articles: Pungency and Scoville scale

Substances such as ethanol and capsaicin cause a burning sensation by inducing a trigeminal nerve reaction together with normal taste reception. The sensation of heat is caused by the food's activating nerves that express TRPV1 and TRPA1 receptors. Two main plant-derived compounds that provide this sensation are capsaicin from chili peppers and piperine from black pepper. The piquant ("hot" or "spicy") sensation provided by chili peppers, black pepper, and other spices like ginger and horseradish plays an important role in a diverse range of cuisines across the world—especially in equatorial and sub-tropical climates, such as Ethiopian, Peruvian, Hungarian, Indian, Korean, Indonesian, Lao, Malaysian, Mexican, Southwest Chinese (including Szechuan cuisine), Vietnamese, and Thai cuisines.

This particular sensation, called Chemesthesis, is not a taste in the technical sense, because the sensation does not arise from taste buds and a different set of nerve fibers carry it to the brain. Foods like chili peppers activate nerve fibers directly; the sensation interpreted as "hot" results from the stimulation of somatosensory (pain/temperature) fibers on the tongue. Many parts of the body with exposed membranes but no taste sensors (such as the nasal cavity, under the fingernails, surface of the eye or a wound) produce a similar sensation of heat when exposed to hotness agents. Asian countries within the sphere of, mainly, Chinese, Indian, and Japanese cultural influence, traditionally consider pungency a sixth basic taste.

Coolness

Some substances activate cold trigeminal receptors even when not at low temperatures. This "fresh" or "minty" sensation can be tasted in spearmint, menthol, ethanol, and camphor. Caused by activation of the same mechanism that signals cold, TRPM8 ion channels on nerve cells, unlike the actual change in temperature described for sugar substitutes, this coolness is only a perceived phenomenon.

Numbness

Both Chinese and Batak Toba cooking include the idea of 麻 (má or mati rasa), a tingling numbness caused by spices such as Sichuan pepper. The cuisines of Sichuan province in China and of the Indonesia province North Sumatra often combine this with chili pepper to produce a 麻辣 málà, "numbing-and-hot", or "mati rasa" flavor.[69] These sensations although not taste fall into a category of Chemesthesis.

Astringency

Page 9: Taste.doc

Some foods, such as unripe fruits, contain tannins or calcium oxalate that cause an astringent or puckering sensation of the mucous membrane of the mouth. Examples include tea, red wine, rhubarb, and unripe persimmons and bananas.

Less exact terms for the astringent sensation are "dry", "rough", "harsh" (especially for wine), "tart" (normally referring to sourness), "rubbery", "hard" or "styptic".[70]

When referring to wine, dry is the opposite of sweet, and does not refer to astringency. Wines that contain tannins and so cause an astringent sensation are not necessarily classified as "dry," and "dry" wines are not necessarily astringent.

In the Indian Ayurvedic tradition, one of the six tastes is astringency (kasaaya).[71]

Metallicness

A metallic taste may be caused by food and drink, certain medicines or amalgam dental fillings. It is generally considered an off flavor when present in food and drink. A metallic taste may be caused by galvanic reactions in the mouth. In the case where it is caused by dental work, the dissimilar metals used may produce a measurable current.[72] Some artificial sweeteners are perceived to have an metallic taste, which is detected by the TRPV1 receptors.[73] Blood is considered by many people to have a metallic taste. [74] A metallic taste in the mouth is also a symptom of various medical conditions, in which case it may be classified under the symptoms dysgeusia or parageusia, referring to distortions of the sense of taste. [74]

Calcium

In 2008, geneticists discovered a CaSR calcium receptor on the tongues of mice. The CaSR receptor is commonly found in the gastrointestinal tract, kidneys, and brain. Along with the "sweet" T1R3 receptor, the CaSR receptor can detect calcium as a taste. Whether closely related genes in mice and humans means the phenomenon exists in humans as well is unknown.[75][76]

Fattiness

Recent research reveals a potential taste receptor called the CD36 receptor that reacts to fat (fatty acids, more specifically).[77] This receptor was found in mice.

Heartiness (kokumi)

Some Japanese researchers refer to the kokumi of foods laden with alcohol and thiol-groups in their amino acid extracts, and this sensation has also been described as mouthfeel.

Temperature

Page 10: Taste.doc

Temperature can be an essential element of the taste experience. Food and drink that—in a given culture—is traditionally served hot is often considered distasteful if cold, and vice versa. For example, alcoholic beverages, with a few exceptions, are usually thought best when served cold, but soups—again, with exceptions—are usually only eaten hot. A cultural example is soda. In North America it is almost always preferred cold, regardless of season. In South America soda is almost exclusively consumed lukewarm in winter.[citation needed]

Other concepts

Supertasters

Main article: Supertaster

A supertaster is a person whose sense of taste is significantly more sensitive than average. The cause of this heightened response is likely, at least in part, due to an increased number of fungiform papillae.[78] Studies have shown that supertasters require less fat and sugar in their food to get the same satisfying effects. However, contrary to what one might think, these people actually tend to consume more salt than the average person. This is due to their heightened sense of the taste of bitterness, and the presence of salt drowns out the taste of bitterness. (This also explains why supertasters prefer salted cheddar cheese over non-salted.)[79]

Aftertaste

Main article: Aftertaste

Aftertastes arise after food has been swallowed. An aftertaste can differ from the food it follows. Medicines and tablets may also have a lingering aftertaste, as can certain artificial flavor compounds, such as aspartame (artificial sweetener).

Acquired taste

Main article: Acquired taste

An acquired taste often refers to an appreciation for a food or beverage that is unlikely to be enjoyed by a person who has not had substantial exposure to it, usually because of some unfamiliar aspect of the food or beverage, including a strong or strange odor, taste, or appearance.

Innervation

Taste is brought to the brainstem by 3 different cranial nerves:

Facial nerve for the anterior 2/3 of the tongue and soft palate.

Page 11: Taste.doc

Glossopharyngeal nerve for the posterior 1/3 of the tongue. Vagus nerve for the small area on the epiglottis.

Disorders of taste

ageusia (complete loss of taste) hypogeusia (reduced sense of taste) dysgeusia (distortion in sense of taste) parageusia (persistent abnormal taste) hypergeusia (abnormally heightened sense of taste)

See also

Food portal

Beefy meaty peptide BitterDB Optimal foraging theory Palatability Vomeronasal organ

Notes

Footnotes

a. ^ It has been known for some time that these categories may not be comprehensive. In Guyton's 1976 edition of Textbook of Medical Physiology, he wrote:

On the basis of physiologic studies, there are generally believed to be at least four primary sensations of taste: sour, salty, sweet, and bitter. Yet we know that a person can perceive literally hundreds of different tastes. These are all supposed to be combinations of the four primary sensations...However, there might be other less conspicuous classes or subclasses of primary sensations",[80]

b. ^ Some variation in values is not uncommon between various studies. Such variations may arise from a range of methodological variables, from sampling to analysis and interpretation. In fact there is a "plethora of methods"[81] Indeed, the taste index of 1, assigned to reference substances such as sucrose (for sweetness), hydrochloric acid (for sourness), quinine (for bitterness), and sodium chloride (for saltiness), is itself arbitrary for practical purposes.[53]

Some values, such as those for maltose and glucose, vary little. Others, such as aspartame and sodium saccharin, have much larger variation. Regardless of variation, the perceived intensity of substances relative to each reference substance remains consistent for taste ranking purposes. The indices table for McLaughlin & Margolskee (1994) for example,[21]

[82] is essentially the same as that of Svrivastava & Rastogi (2003),[83] Guyton & Hall

Page 12: Taste.doc

(2006),[53] and Joesten et al. (2007).[50] The rankings are all the same, with any differences, where they exist, being in the values assigned from the studies from which they derive.

As for the assignment of 1 or 100 to the index substances, this makes no difference to the rankings themselves, only to whether the values are displayed as whole numbers or decimal points. Glucose remains about three-quarters as sweet as sucrose whether displayed as 75 or 0.75.

Citations

1. Jump up ̂ Adjectival form: gustatory2. ^ Jump up to: a b What Are Taste Buds? kidshealth.org3. Jump up ̂ Human biology (Page 201/464) Daniel D. Chiras. Jones &

Bartlett Learning, 2005.4. ^ Jump up to: a b Schacter, Daniel (2009). Psychology Second Edition.

United States of America: Worth Publishers. p. 169. ISBN 13:978-1-4292-3719-2 Check |isbn= value (help).

5. Jump up ̂ Boron, W.F., E.L. Boulpaep. 2003. Medical Physiology. 1st ed. Elsevier Science USA.

6. Jump up ̂ Human Physiology: An integrated approach 5th Edition -Silverthorn, Chapter-10, Page-354

7. ^ Jump up to: a b Why do two great tastes sometimes not taste great together? scientificamerican.com. Dr. Tim Jacob, Cardiff University. May 22, 2009.

8. Jump up ̂ Miller, Greg (2). "Sweet here, salty there: Evidence of a taste map in the mammilian brain.". Science 333 (6047): 1213. doi:10.1126/science.333.6047.1213.

9. Jump up ̂ Smell - The Nose Knows washington.edu, Eric H. Chudler.10. Jump up ̂

Food texture: measurement and perception (page 36/311) Andrew J. Rosenthal. Springer, 1999.

Food texture: measurement and perception (page 3/311) Andrew J. Rosenthal. Springer, 1999.

11. Jump up ̂ Food texture: measurement and perception (page 4/311) Andrew J. Rosenthal. Springer, 1999.

12. Jump up ̂ On the Soul Aristotle. Translated by J. A. Smith. The Internet Classics Archive.

13. Jump up ̂ Aristotle's De anima (422b10-16) Ronald M. Polansky. Cambridge University Press, 2007.

14. Jump up ̂ Origins of neuroscience: a history of explorations into brain function (Page 165/480) Stanley Finger. Oxford University Press US, 2001.

15. Jump up ̂ Ayurvedic balancing: an integration of Western fitness with Eastern wellness (Pages 25-26/188) Joyce Bueker. Llewellyn Worldwide, 2002.

Page 13: Taste.doc

16. Jump up ̂ Bachmanov, A. A., and G. K. Beauchamp (2007), "Taste receptor genes", Annu Rev Nutr 27: 389–414, doi:10.1146/annurev.nutr.26.061505.111329, PMC 2721271, PMID 17444812.

17. Jump up ̂ Chandrashekar J, Kuhn C, Oka Y, et al. (March 2010). "The cells and peripheral representation of sodium taste in mice". Nature 464 (7286): 297–301. doi:10.1038/nature08783. PMC 2849629. PMID 20107438.

18. Jump up ̂ Laugerette, Fabienne; Patricia Passilly-Degrace, Bruno Patris,

Isabelle Niot, Maria Febbraio, Jean-Pierre Montmayeur, Philippe Besnard (November 2005), "CD36 involvement in orosensory detection of dietary lipids, spontaneous fat preference, and digestive secretions" (PDF), The Journal of Clinical Investigation 115 (11): 3177–3184, doi:10.1172/JCI25299, PMC 1265871, PMID 16276419, retrieved 2007-12-28.

Abumrad, Nada A. (November 2005), "CD36 may determine our desire for dietary fats" (PDF), The Journal of Clinical Investigation 115 (11): 2965–2967, doi:10.1172/JCI26955, PMC 1265882, PMID 16276408, retrieved 2007-12-28.

Boring, Edwin G. (1942), Sensation and Perception in the History of Experimental Psychology, Appleton Century Crofts, p. 453

19. Jump up ̂ Ikeda, Kikunae (2002) [First published 1909]. "New Seasonings" (PDF). Chemical Senses 27 (9): 847–849. doi:10.1093/chemse/27.9.847. PMID 12438213. Retrieved 2007-12-30.

20. Jump up ̂ Zhao, Grace Q.; Yifeng Zhang, Mark A. Hoon, Jayaram Chandrashekar, Isolde Erlenbach, Nicholas J.P. Ryba, Charles S. Zuker (October 2003). "The Receptors for Mammalian Sweet and Savory taste" (PDF). Cell 115 (3): 255–266. doi:10.1016/S0092-8674(03)00844-4. PMID 14636554. Retrieved 2007-12-30.

21. ^ Jump up to: a b c d e f g h i j k Guyton, Arthur C. (1991) Textbook of Medical Physiology. (8th ed). Philadelphia: W.B. Saunders

22. ^ Jump up to: a b c d e f McLaughlin S., Margolskee R.F. (1994). "The Sense of Taste". American Scientist 82 (6): 538–545.

23. Jump up ̂ "Biologists Discover How We Detect Sour Taste". Sciencedaily.com. 2006-08-24. Retrieved 2012-08-04.

24. Jump up ̂ Djin Gie Liem and Julie A. Mennella (February 2003). "Heightened Sour Preferences During Childhood". Chem Senses 28 (2): 173–180.

25. Jump up ̂ http://www.hersheys.com/vending/lib/pdf/sellsheets/SweetSourSS.pdf

26. ^ Jump up to: a b Logue, A.W. (1986) The Psychology of Eating and Drinking. New York: W.H. Freeman & Co.

27. Jump up ̂ Glendinning, J. I. (1994). "Is the bitter rejection response always adaptive?". Physiol Behav 56 (6): 1217–1227. doi:10.1016/0031-9384(94)90369-7. PMID 7878094.

28. Jump up ̂ Jones, S., Martin, R., & Pilbeam, D. (1994) The Cambridge Encyclopedia of Human Evolution. Cambridge: Cambridge University Press

Page 14: Taste.doc

29. Jump up ̂ Johns, T. (1990). With Bitter Herbs They Shall Eat It: Chemical ecology and the origins of human diet and medicine. Tucson: University of Arizona Press

30. Jump up ̂ Maehashi, K., M. Matano, H. Wang, L. A. Vo, Y. Yamamoto, and L. Huang (2008). "Bitter peptides activate hTAS2Rs, the human bitter receptors". Biochem Biophys Res Commun 365 (4): 851–855. doi:10.1016/j.bbrc.2007.11.070. PMC 2692459. PMID 18037373.

31. Jump up ̂ Lindemann, Bernd (13 September 2001). "Receptors and transduction in taste" (PDF). Nature 413 (6852): 219–225. doi:10.1038/35093032. PMID 11557991. Retrieved 2007-12-30.

32. Jump up ̂ Meyerhof (2010). doi:10.1093/chemse/bjp092 http://chemse.oxfordjournals.org/content/35/2/157.long. Missing or empty |title= (help)

33. Jump up ̂ Wiener (2012). "BitterDB: a database of bitter compounds". Nucleic Acids Res. 40 (Database issue): D413–9. doi:10.1093/nar/gkr755. PMC 3245057. PMID 21940398.

34. Jump up ̂ Wang, X., S. D. Thomas, and J. Zhang (2004). "Relaxation of selective constraint and loss of function in the evolution of human bitter taste receptor genes". Hum Mol Genet 13 (21): 2671–2678. doi:10.1093/hmg/ddh289. PMID 15367488.

35. Jump up ̂ Wooding, S., U. K. Kim, M. J. Bamshad, J. Larsen, L. B. Jorde, and D. Drayna (2004). "Natural selection and molecular evolution in PTC, a bitter-taste receptor gene". Am J Hum Genet 74 (4): 637–646. doi:10.1086/383092. PMC 1181941. PMID 14997422.

36. Jump up ̂ "You say savory, I say umami" . Issie Lapowsky (9 February 2010). "Umami, savory 'fifth taste,'

now available in a tube in grocery stores". New York: NY Daily News. Retrieved 1 January 2011.

"Cambridge Advanced Learner's Dictionary" . Cambridge University Press. Retrieved 1 January 2011.

37. ^ Jump up to: a b "Merriam-Webster English Dictionary". Merriam-Webster, Incorporated. Retrieved 1 January 2011.

38. Jump up ̂ "New Seasonings".39. ^ Jump up to: a b What Is Umami?: Umami culture around the world

Umami Information Center40. ^ Jump up to: a b c "The Claim: The tongue is mapped into four areas of

taste. Anahad O'connor.", The New York Times, November 10, 2008: Health section, retrieved 13 September 2010  May require free registration to view

41. Jump up ̂ Monosodium Glutamate: The molecule that enhances taste in food

Pio Monti. chm.bris.ac.uk Ikeda, Kikunae (2002), "New Seasonings" (PDF), Chemical Senses

27 (9): 847–849, doi:10.1093/chemse/27.9.847, PMID 12438213, retrieved 2007-12-30.

Page 15: Taste.doc

Nelson G, Chandrashekar J, Hoon MA, et al. (2002), "An amino-acid taste receptor", Nature 416 (6877): 199–202, doi:10.1038/nature726, PMID 11894099.

42. Jump up ̂ 旨味 definition in English Denshi Jisho — Online Japanese dictionary

43. ^ Jump up to: a b c Umami Food Ingredients Japan's Ministry of Agriculture, Forestry and Fisheries. 2007.

44. Jump up ̂ Yamaguchi, Shizuko & Ninomiya, Kumiko (1999), "Umami and Food Palatability", in Roy Teranishi, Emily L. Wick, & Irwin Hornstein (editors), Flavor Chemistry: Thirty Years of Progress, Proceedings of an American Chemical Society Symposium, held August 23–27, 1998, in Boston, Massachusetts, Published in New York: Kluwer Academic/Plenum Publishers, pp. 423–432, ISBN 0-306-46199-4, retrieved 13 September 2010

45. Jump up ̂ "What exactly is umami?". The Umami Information Center.46. Jump up ̂ Lindemann, Bernd (February 2000). "A taste for Umami

taste" (PDF). Nature Neuroscience 3 (2): 99–100. doi:10.1038/72153. PMID 10649560. Retrieved 2007-12-30.

47. Jump up ̂ Chaudhari, Nirupa; Ana Marie Landin, Stephen D. Roper (February 2000). "A metabotropic glutamate receptor variant functions as a taste receptor" (PDF). Nature Neuroscience 3 (2): 113–119. doi:10.1038/72053. PMID 10649565. Retrieved 2007-12-30.

48. ^ Jump up to: a b Tsai, Michelle (14 May 2007), "How Sweet It Is? Measuring the intensity of sugar substitutes", Slate (The Washington Post Company), retrieved 14 September 2010

49. Jump up ̂ Walters, D. Eric (Last updated 13 May 2008), "How is Sweetness Measured?", All About Sweeteners, retrieved 15 September 2010

50. ^ Jump up to: a b Joesten, Melvin D; Hogg, John L; Castellion, Mary E (2007), "Sweeteness Relative to Sucrose (table)", The World of Chemistry: Essentials (4th ed.), Belmont, California: Thomson Brooks/Cole, p. 359, ISBN 0-495-01213-0, retrieved 14 September 2010

51. Jump up ̂ Coultate,Tom P (2009), "Sweetness relative to sucrose as an arbitrary standard", Food: The Chemistry of its Components (5th ed.), Cambridge, UK: Royal Society of Chemistry, pp. 268–269, ISBN 978-0-85404-111-4, retrieved 15 September 2010

52. Jump up ̂ Mehta, Bhupinder & Mehta, Manju (2005), "Sweetness of sugars", Organic Chemistry, India: Prentice-Hall, p. 956, ISBN 81-203-2441-2, retrieved 15 September 2010  Alternative ISBN 978-81-203-2441-1

53. ^ Jump up to: a b c Guyton, Arthur C; Hall, John; Hall, John E. (2006), Guyton and Hall Textbook of Medical Physiology (11th ed.), Philadelphia: Elsevier Saunders, p. 664, ISBN 0-7216-0240-1  International ISBN 0-8089-2317-X

54. Jump up ̂ Food Chemistry (Page 38/1070) H. D. Belitz, Werner Grosch, Peter Schieberle. Springer, 2009.

55. ^ Jump up to: a b c Quality control methods for medicinal plant materials, Pg. 38 World Health Organization, 1998.

Page 16: Taste.doc

56. Jump up ̂ How the Taste Bud Translates Between Tongue and Brain nytimes.com, August 4, 1992.

57. Jump up ̂ Zhao, Grace Q.; Yifeng Zhang, Mark A. Hoon, Jayaram Chandrashekar, Isolde Erlenbach, Nicholas J.P. Ryba, Charles S. Zuker (October 2003), "The Receptors for Mammalian Sweet and Savory taste" (PDF), Cell 115 (3): 255–266, doi:10.1016/S0092-8674(03)00844-4, PMID 14636554, retrieved 2007-12-30.

58. Jump up ̂ outlines of chemistry with practical work (Page 241) Henry John Horstman Fenton. CUP Archive.

59. Jump up ̂ Focus Ace Pmr 2009 Science (Page 242/522) Chang See Leong, Chong Kum Ying,Choo Yan Tong & Low Swee Neo. Focus Ace Pmr 2009 Science.

60. ^ Jump up to: a b c channels in sensory cells (Page 155/304) Stephan Frings, Jonathan Bradley. Wiley-VCH, 2004.

61. Jump up ̂ "Biologists Discover How We Detect Sour Taste", Science Daily, August 24, 2006, retrieved 12 September 2010

62. Jump up ̂ Maehashi, K., M. Matano, H. Wang, L. A. Vo, Y. Yamamoto, and L. Huang (2008), "Bitter peptides activate hTAS2Rs, the human bitter receptors", Biochem Biophys Res Commun 365 (4): 851–855, doi:10.1016/j.bbrc.2007.11.070, PMC 2692459, PMID 18037373.

63. Jump up ̂ Lindemann, Bernd (13 September 2001), "Receptors and transduction in taste" (PDF), Nature 413 (6852): 219–225, doi:10.1038/35093032, PMID 11557991, retrieved 2007-12-30.

64. ^ Jump up to: a b What Is Umami?: What Exactly is Umami? Umami Information Center

65. Jump up ̂ Chandrashekar, Jayaram; Hoon, Mark A; Ryba , Nicholas J. P. & Zuker, Charles S (16 November 2006), "The receptors and cells for mammalian taste", Nature 444 (7117): 288–294, doi:10.1038/nature05401, PMID 17108952, retrieved 13 September 2010

66. ^ Jump up to: a b What Is Umami?: The Composition of Umami Umami Information Center

67. Jump up ̂ Lindemann, Bernd (February 2000), "A taste for Umami taste" (PDF), Nature Neuroscience 3 (2): 99–100, doi:10.1038/72153, PMID 10649560, retrieved 2007-12-30.

68. Jump up ̂ Chaudhari, Nirupa; Ana Marie Landin, Stephen D. Roper (February 2000), "A metabotropic glutamate receptor variant functions as a taste receptor" (PDF), Nature Neuroscience 3 (2): 113–119, doi:10.1038/72053, PMID 10649565, retrieved 2007-12-30.

69. Jump up ̂ Spice Pages: Sichuan Pepper (Zanthoxylum, Szechwan peppercorn, fagara, hua jiao, sansho 山椒 , timur, andaliman, tirphal)

70. Jump up ̂ "Bitterness and astringency of flavan-3-ol monomers, dimers and trimers - Peleg - 1999 - Journal of the Science of Food and Agriculture - Wiley Online Library". .interscience.wiley.com. Retrieved 2012-08-04.

71. Jump up ̂ [1][dead link]

72. Jump up ̂ "Is there a Battery in your Mouth?". www.toothbody.com. Retrieved 2012-02-10.

Page 17: Taste.doc

73. Jump up ̂ "Artificial sweeteners and salts producing a metallic taste sensation activate TRPV1 receptors.". Nestlé Research Center. 2007-06-13. Retrieved 2012-02-10.

74. ^ Jump up to: a b Does Anxiety Cause a Metallic Taste in Your Mouth?, Calm Clinic. Retrieved Mar 2013.

75. Jump up ̂ Tordorf, Michael G. (2008), "Chemosensation of Calcium", American Chemical Society National Meeting, Fall 2008, 236th, Philadelphia, PA: American Chemical Society, AGFD 207

76. Jump up ̂ "That Tastes ... Sweet? Sour? No, It's Definitely Calcium!", Science Daily, August 21, 2008, retrieved 14 September 2010

77. Jump up ̂ Potential Taste Receptor for Fat Identified: Scientific American

78. Jump up ̂ Bartoshuk L. M., Duffy V. B. et al. (1994). "PTC/PROP tasting: anatomy, psychophysics, and sex effects." 1994". Physiol Behav 56 (6): 1165–71.

79. Jump up ̂ Gardner, Amanda (16 June 2010). "Love salt? You might be a 'supertaster'". CNN Health. Retrieved 9 April 2012.

80. Jump up ̂ Guyton, Arthur C. (1976), Textbook of Medical Physiology (5th ed.), Philadelphia: W.B. Saunders, p. 839, ISBN 0-7216-4393-0

81. Jump up ̂ Macbeth, Helen M. & MacClancy, Jeremy, ed. (2004), "plethora of methods characterising human taste perception", Researching Food Habits: Methods and Problems, The anthropology of food and nutrition, Vol. 5, New York: Berghahn Books, pp. 87–88, ISBN 1-57181-544-9, retrieved 15 September 2010=  Paperback ISBN 1-57181-545-7

82. Jump up ̂ McLaughlin, Susan, & Margolskee, Rorbert F (November–December 1994), The Sense of Taste American Scientist 82 (6), pp. 538–545

83. Jump up ̂ Svrivastava, R.C. & Rastogi, R.P (2003), "Relative taste indices of some substances", in ., Transport Mediated by Electrical Interfaces, Studies in interface science, vol.18, Amsterdam, Netherlands: Elsevier Science, ISBN 0-444-51453-8 B.V, retrieved 12 September 2010  Taste indices of table 9, p.274 are select sample taken from table in Guyton's Textbook of Medical Physiology (present in all editions)

Reference #30 (Wooding et al.) is helpful, but it is incorrect. The discovery that variants in the TAS2R38 gene underlie the ability to taste PTC and PROP was reported a year earlier in: Kim, U.-K., Jorgenson, E., Coon, H., Leppert, M., Risch, N., and D. Drayna. Positional Cloning of the human quantitative trait locus underlying taste sensitivity to phenylthiocarbamide. Science 299:1221-1225 (2003). I was the senior and communicating author on both of these papers.

Dennis Drayna, PhD NIDCD/National Institutes of Health

Further reading

The Science of taste at Kitchen Geekery. An informative article about the science behind taste. Written from a culinary science perspective.

Page 18: Taste.doc

Bartoshuk, Linda M (June 1978), "The Psychophysics of Taste", American Journal of Clinical Nutrition 31 (6): 1068–1077, PMID 352127, retrieved 12 September 2010

Chandrashekar, Jayaram; Hoon, Mark A; Ryba , Nicholas J. P. & Zuker, Charles S (16 November 2006), "The receptors and cells for mammalian taste", Nature 444 (7117): 288–294, doi:10.1038/nature05401, PMID 17108952, retrieved 13 September 2010

Chaudhari, Nirupa & Roper, Stephen D (2010), "The cell biology of taste", Journal of Cell Biology 190 (3): 285–296, doi:10.1083/jcb.201003144, PMC 2922655, PMID 20696704, retrieved 13 September 2010

Danker, W.H (1968), Basic Principles of Sensory Evaluation, Philadelphia: American Society for Testing and Materials, ISBN 978-0-8031-4572-6, retrieved 13 September 2010

Dulac, Catherine (March 17, 2000), "The Physiology of Taste, Vintage 2000", Cell 100 (6): 607–610, doi:10.1016/S0092-8674(00)80697-2, PMID 10761926, retrieved 13 September 2010

Finger, Thomas E, ed. (2009), International Symposium on Olfaction and Taste, Boston: Blackwell, for the New York Academy of Sciences, ISBN 1-57331-738-1, retrieved 12 September 2010 Alternative ISBN 978-1-57331-738-2

Hui, Y.H, ed. (2010), Handbook of Fruit and Vegetable Flavors, Hoboken, New Jersey: John Wiley & Sons, ISBN 978-0-470-22721-3, retrieved 13 September 2010  See especially comments and key references in regards taste

Thomas Hummel & Antje Welge-Lüssen, ed. (2006), Tast and Smell: An Update, Advances in Oto-Rhino-Laryngolog, Vol.63, Basel, Switzerland: Karger, ISBN 3-8055-8123-8, retrieved 12 September 2010

Lawless, Harry T., & Heymann, Hildegarde (1998), Sensory Evaluation of Food: Principles and Practices, New York: Kluwer Academic/Plenum Publishers, ISBN 0-8342-1752-X, retrieved 13 September 2010

Macbeth, Helen, ed. (2006), Food Preferences and Taste: Continuity and Change, The Anthropology of Food and Nutrition, Vol.2, Providence, Rhode Island: Berghahn Books, ISBN 1-57181-958-4, retrieved 12 September 2010 Paperback ISBN 1-57181-970-3

Patton, Harry D (March 1950), "Physiology of Smell and Taste", Annual Review of Physiology 12: 469–484, doi:10.1146/annurev.ph.12.030150.002345, PMID 15411178, retrieved 12 September 2010

Reed, Danielle R; Tanaka, Toshiko; and McDaniel, Amanda H (June 30, 2006), "Diverse tastes: Genetics of sweet and bitter perception", Physiology & Behavior 88 (3): 215–226, doi:10.1016/j.physbeh.2006.05.033, PMC 1698869, PMID 16782140

Reineccius, Gary, ed. (1999), Source Book of Flavours (2nd ed.), Gaithersburg, Maryland: Aspen, ISBN 0-8342-1307-9, retrieved 12 September 2010  Previously published 1994 by Chapman & Hall, New York ISBN 0-442-00376-5

Schiffman, Susan S (26 May 1983), "Taste and smell in disease (First of two parts)", The New England Journal of Medicine 308 (21): 1275–1279

Page 19: Taste.doc

Schiffman, Susan S; Schiffman, Susan S. (2 June 1983), "Taste and smell in disease (Second of two parts)", The New England Journal of Medicine 308 (22): 1337–1343, doi:10.1056/NEJM198306023082207, PMID 6341845

Schiffman, S.S; Graham, B.G (2000), "Taste and smell perception affect appetite and immunity in the elderly" (PDF), European Journal of Clinical Nutrition 54 (Suppl. 3): S54–S63, PMID 11041076, retrieved 16 June 2010

Seiden, Allen M, ed. (1997), Taste and Smell Disorders, Rhinology and Sinusology, New York: Thieme, ISBN 0-86577-533-8, retrieved 12 September 2010 Alternative ISBN 3-13-107261-X

Shallenberger, R.S (1993), Taste Chemistry, London & New York: Blackie Academic & Professional (imprint of Chapman & Hall), ISBN 0-7514-0150-1, retrieved 12 September 2010

Svrivastava, R.C. & Rastogi, R.P (2003), "Relative taste indices of some substances", in ., Transport Mediated by Electrical Interfaces, Studies in interface science, vol.18, Amsterdam, Netherlands: Elsevier Science, ISBN 0-444-51453-8 B.V, retrieved 12 September 2010  Taste indices of table 9, p.274 are select sample taken from table in Guyton's Textbook of Medical Physiology (present in all editions)

Xiaodong Li, Lena Staszewski, Hong Xu, Kyle Durick, Mark Zoller, and Elliot Adler (April 2, 2002), "Human receptors for sweet and umami taste", Proceedings of the National Academy of Sciences 99 (7): 4692–4696, doi:10.1073/pnas.072090199, PMC 123709, PMID 11917125, retrieved 13 September 2010

External links

Look up sour in Wiktionary, the free dictionary.

Wikimedia Commons has media related to Taste.

Researchers Define Molecular Basis of Human "Sweet Tooth" and Umami Taste Statistics on Taste at National Institute on Deafness and Other Communication

Disorders. An informative overview with good list of references. The Science of taste at Kitchen Geekery. An informative article about the science

behind taste. Written from a culinary science perspective.

[show] v t e

Taste

[show] v

Page 20: Taste.doc

t e

Nervous system: Sensory systems / senses (TA A15)Categories:

Sensory systems Gustation Gustatory system

Navigation menu

Create account Log in

Article Talk

Read Edit View history

Main page Contents Featured content Current events Random article Donate to Wikipedia

Interaction

Help About Wikipedia Community portal Recent changes Contact page

Toolbox

Print/export

Languages

العربية

Page 21: Taste.doc

ܐܪܡܝܐ Asturianu Azərbaycanca বাং��লা� Беларуская Български Bosanski Català Česky Dansk Deutsch Ελληνικά Español Esperanto Euskara فارسی Français Gàidhlig Galego 한국어 Hrvatski Bahasa Indonesia Interlingua Italiano עברית ಕನ್ನ�ಡ Kurdî Кыргызча Latviešu Lëtzebuergesch Lietuvių Magyar മലയാ�ളം� मरा�ठी� Bahasa Melayu Nederlands ने�पा�ल भा�षा� 日本語 Norsk bokmål Polski Português Română Runa Simi Русиньскый Русский Simple English

Page 22: Taste.doc

Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska தமி�ழ் తెలు�గు� ไทย Türkçe Українська Tiếng Việt Võro Walon יִידיש 中文 Edit links

This page was last modified on 14 October 2013 at 04:55. Text is available under the Creative Commons Attribution-ShareAlike License;

additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

Privacy policy About Wikipedia Disclaimers Contact Wikipedia Developers Mobile view