Our website is made possible by displaying online advertisements to our visitors.
Please consider supporting us by disabling your ad blocker.

Responsive image


Taste

Taste bud

The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor).[1] Taste is the perception produced or stimulated when a substance in the mouth reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with olfaction and trigeminal nerve stimulation (registering texture, pain, and temperature), determines flavors of food and other substances. Humans have taste receptors on taste buds and other areas including the upper surface of the tongue and the epiglottis.[2][3] The gustatory cortex is responsible for the perception of taste.

The tongue is covered with thousands of small bumps called papillae, which are visible to the naked eye.[2] Within each papilla are hundreds of taste buds.[1][4] The exception to this is the filiform papillae that do not contain taste buds. 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 receptors in the mouth sense the five taste modalities: sweetness, sourness, saltiness, bitterness, and savoriness (also known as savory or umami).[1][2][6][7] Scientific experiments have demonstrated that these five tastes exist and are distinct from one another. Taste buds are able to distinguish between different tastes through detecting interaction with different molecules or ions. Sweet, savoriness, 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.[8]

The basic taste modalities contribute only partially to the sensation and flavor of food in the mouth—other factors include smell,[1] 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.

As the gustatory system senses both harmful and beneficial things, all basic taste modalities are classified as either aversive or appetitive, depending upon the effect the things they sense have on our bodies.[12] Sweetness helps to identify energy-rich foods, while bitterness serves as a warning sign of poisons.[13]

Among humans, taste perception begins to fade at an older age because of loss of tongue papillae and a general decrease in saliva production.[14] Humans can also have distortion of tastes (dysgeusia). Not all mammals share the same taste modalities: some rodents can taste starch (which humans cannot), cats cannot taste sweetness, and several other carnivores including hyenas, dolphins, and sea lions, have lost the ability to sense up to four of their ancestral five taste modalities.[15]

  1. ^ a b c d Trivedi, Bijal P. (2012). "Gustatory system: The finer points of taste". Nature. 486 (7403): S2–S3. Bibcode:2012Natur.486S...2T. doi:10.1038/486s2a. ISSN 0028-0836. PMID 22717400. S2CID 4325945.
  2. ^ a b c Witt, Martin (2019). "Anatomy and development of the human taste system". Smell and Taste. Handbook of Clinical Neurology. 164. pp. 147–171. doi:10.1016/b978-0-444-63855-7.00010-1. ISBN 978-0-444-63855-7. ISSN 0072-9752. PMID 31604544. S2CID 204332286.
  3. ^ Human biology (Page 201/464) Daniel D. Chiras. Jones & Bartlett Learning, 2005.
  4. ^ Schacter, Daniel (2009). Psychology Second Edition. United States of America: Worth Publishers. p. 169. ISBN 978-1-4292-3719-2.
  5. ^ Boron, W.F., E.L. Boulpaep. 2003. Medical Physiology. 1st ed. Elsevier Science USA.
  6. ^ Kean, Sam (Fall 2015). "The science of satisfaction". Distillations Magazine. 1 (3): 5. Retrieved 20 March 2018.
  7. ^ "How does our sense of taste work?". PubMed. 6 January 2012. Retrieved 5 April 2016.
  8. ^ Human Physiology: An integrated approach 5th Edition -Silverthorn, Chapter-10, Page-354
  9. ^ Smell - The Nose Knows washington.edu, Eric H. Chudler.
  10. ^
  11. ^ Food texture: measurement and perception (page 4/311) Andrew J. Rosenthal. Springer, 1999.
  12. ^ Why do two great tastes sometimes not taste great together? scientificamerican.com. Dr. Tim Jacob, Cardiff University. 22 May 2009.
  13. ^ Miller, Greg (2 September 2011). "Sweet here, salty there: Evidence of a taste map in the mammilian brain". Science. 333 (6047): 1213. Bibcode:2011Sci...333.1213M. doi:10.1126/science.333.6047.1213. PMID 21885750.
  14. ^ Henry M Seidel; Jane W Ball; Joyce E Dains (1 February 2010). Mosby's Guide to Physical Examination. Elsevier Health Sciences. p. 303. ISBN 978-0-323-07357-8.
  15. ^ Scully, Simone M. (9 June 2014). "The Animals That Taste Only Saltiness". Nautilus. Retrieved 8 August 2014.

Previous Page Next Page