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Umami

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This is an old revision of this page, as edited by Pnm (talk | contribs) at 21:05, 12 May 2012 (Edit to remove original research in lead sentence. Some reliable sources here, but they do not support "popularly referred to as 'savoriness'". foodprocessing.com can't be used as a source at all, and umamiinfo is questionable.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Ripe tomatoes are rich in umami components.

Umami /uːˈmɑːmi/ is a savory taste,[1][2][3] and one of the five basic tastes, together with sweet, sour, bitter, and salty. Umami is a loanword from the Japanese umami (うま味) meaning "pleasant savory taste".[4] This particular writing was chosen by Professor Kikunae Ikeda from umai (うまい) "delicious" and mi (味) "taste". The kanji 旨味 are used for a more general meaning to describe a food as delicious.

The human tongue has receptors for L-glutamate, which is the source of umami flavor. As such, scientists consider umami to be distinct from saltiness.[5]

Background

Scientists debated whether umami was indeed a basic taste ever since Kikunae Ikeda proposed its existence in 1908.[6] Finally in 1985, at the first Umami International Symposium in Hawaii, the term umami was officially recognized as the scientific term to describe the taste of glutamates and nucleotides.[7] Now it is widely accepted as the fifth basic taste. Umami represents the taste of the amino acid L-glutamate and 5’-ribonucleotides such as guanosine monophosphate (GMP) and inosine monophosphate (IMP).[8] Although it can be described as a pleasant "brothy" or "meaty" taste with a long lasting, mouthwatering and coating sensation over the tongue, umami has no translation. Umami is umami in all major languages, including English, Spanish and French. The sensation of umami is due to the detection of the carboxylate anion of glutamate in specialized receptor cells present on the human and other animal tongues.[9][10] Its fundamental effect is the ability to balance taste and round the total flavor of a dish. Umami clearly enhances the palatability of a wide variety of foods (for review Beauchamp, 2009).[11] Glutamate in acid form (glutamic acid) imparts little umami taste; whereas the salts of glutamic acid, known as glutamates, can easily ionize and give the characteristic umami taste. GMP and IMP amplify the taste intensity of glutamate.[10][12]

Discovery of umami taste

Kikunae Ikeda

Glutamate has a long history in cooking.[13] Fermented fish sauces (garum), rich in glutamate, were already used in ancient Rome.[14] In the late 1800s, chef Auguste Escoffier, who opened one of the most glamorous, expensive, and revolutionary restaurants in Paris, created meals that combined umami with salty, sour, sweet and bitter tastes.[15] He did not know the chemical source for this unique quality, however.

Umami was not properly identified until 1908 by Kikunae Ikeda,[16] a professor of the Tokyo Imperial University. He found that glutamate was responsible for the palatability of the broth from kombu seaweed. He noticed that the taste of kombu dashi was distinct from sweet, sour, bitter and salty and named it umami.

Professor Shintaro Kodama, a disciple of Ikeda, discovered in 1913 that dried bonito flakes contained another umami substance.[17] This was the ribonucleotide IMP. In 1957, Akira Kuninaka realized that the ribonucleotide GMP present in shiitake mushrooms also conferred the umami taste.[18] One of Kuninaka's most important discoveries was the synergistic effect between ribonucleotides and glutamate. When foods rich in glutamate are combined with ingredients that have ribonucleotides, the resulting taste intensity is higher than the sum of both ingredients.

This synergy of umami provides an explanation for various classical food pairings, starting with why Japanese make dashi with kombu seaweed and dried bonito flakes, and continuing with various other dishes: Chinese add Chinese leek and cabbage with chicken soup, as in the similar Scottish dish of cock-a-leekie soup, and Italians combine Parmesan cheese on tomato sauce with mushrooms. The umami taste sensation of those ingredients mixed together surpasses the taste of each one alone.

Properties of umami taste

Umami has a mild but lasting aftertaste difficult to describe. It induces salivation and a sensation of furriness on the tongue, stimulating the throat, the roof and the back of the mouth (for review Yamaguchi, 1998).[19][20] By itself, umami is not palatable, but it makes a great variety of foods pleasant especially in the presence of a matching aroma.[21] But like other basic tastes, with the exception of sucrose, umami is pleasant only within a relatively narrow concentration range.[19] The optimum umami taste depends also on the amount of salt, and at the same time, low-salt foods can maintain a satisfactory taste with the appropriate amount of umami.[22] In fact, Roinien et al. showed that ratings on pleasantness, taste intensity and ideal saltiness of low-salt soups were greater when the soup contained umami, whereas low-salt soups without umami were less pleasant.[23] Some population groups, such as the elderly, may benefit from umami taste because their taste and smell sensitivity is impaired by age and multiple medications. The loss of taste and smell can contribute to poor nutrition, increasing their risk of disease.[24]

Foods rich in umami

Many foods that may be consumed daily are rich in umami. Naturally occurring glutamate can be found in meats and vegetables, whereas inosinate comes primarily from meats and guanylate from vegetables. Thus, umami taste is common to foods that contain high levels of L-glutamate, IMP and GMP, most notably in fish, shellfish, cured meats, vegetables (e.g., mushrooms, ripe tomatoes, Chinese cabbage, spinach, celery, etc.) or green tea, and fermented and aged products (e.g., cheeses, shrimp pastes, soy sauce, etc.).[25]

Humans' first encounter with umami is often breast milk.[26] It contains roughly the same amount of umami as broths.

There are some distinctions among stocks from different countries. Japanese dashi gives a very pure umami taste sensation because it is not based on meats. In dashi, L-glutamate comes from sea kombu (Laminaria japonica) and inosinate from dried bonito flakes (katsuobushi) or small dried sardines (niboshi). In contrast, Western or Chinese broths have a more complex taste because of a wider mixture of amino acids from bones, meats and vegetables. Iberian Ham tastes umami as well.

Taste receptors

All taste buds on the tongue and other regions of the mouth can detect umami taste independently of their location. The tongue map in which different tastes are distributed in different regions of the tongue is a common misconception. Biochemical studies have identified the taste receptors responsible for the sense of umami, a modified form of mGluR4, mGluR1 and taste receptor type 1 (T1R1 + T1R3), and all have been found in taste buds from any region of tongue.[27][28][29] The New York Academy of Sciences corroborated the acceptance of these receptors stating that "Recent molecular biological studies have now identified strong candidates for umami receptors, including the heterodimer T1R1/T1R3, and truncated type 1 and 4 metabotropic glutamate receptors missing most of the N-terminal extracellular domain (taste-mGluR4 and truncated-mGluR1) and brain-mGluR4."[9] Receptors mGluR1 and mGluR4 are specific to glutamate whereas T1R1 + T1R3 are responsible for the synergism already described by Akira Kuninaka in 1957. However, the specific role of each type of receptor in taste bud cells remains unclear. They are G protein-coupled receptors (GPCRs) with similar signaling molecules that include G proteins beta-gamma, PLCb2 and PI3-mediated release of calcium (Ca2+) from intracellular stores.[30] Ca2+ activates the selective cation channel transient receptor potential melastatin 5 (TrpM5) that leads to membrane depolarization and the consequent release of ATP and secretion of neurotransmitters including serotonin.[31][32][33][34] Cells responding to umami taste stimuli do not possess typical synapses, but ATP conveys taste signals to gustatory nerves and in turn to the brain that interprets and identifies the taste quality.[35][36]

Notes

  1. ^ Heidi Blake (9 February 2010). "Umami in a tube: 'fifth taste' goes on sale in supermarkets". The Daily Telegraph. Retrieved 10 February2011. {{cite web}}: Check date values in: |accessdate= (help)
  2. ^ "Cambridge Advanced Learner's Dictionary". Cambridge University Press. Retrieved 1 January 2011.
  3. ^ "Merriam-Webster English Dictionary". Merriam-Webster, Incorporated. Retrieved 1 January 2011.
  4. ^ Jim Breen. "[[EDICT]]'s entry for umami". Retrieved 31 December 2010. {{cite web}}: URL–wikilink conflict (help)
  5. ^ Sweet, Sour, Salty, Bitter ... and Umami, NPR
  6. ^ Lindemann, Bernd; Ogiwara, Yoko; Ninomiya, Yuzo. "The Discovery of Umami". Oxford Journals..
  7. ^ Y. Kawamura and M.R. Kare, ed. (1987). Umami: A basic taste,. New York,NJ: Marcel Dekker.
  8. ^ Yamaguchi S, Kumiko N (2000). "Umami and Food Palatability". Journal of Nutrition. 130 (4): 921S–26S. PMID 10736353. {{cite journal}}: Unknown parameter |month= ignored (help)
  9. ^ a b Thomas E. Finger, ed. (2009). International Symposium on Olfaction and Taste, Volume 1170. Hoboken,NJ: The Annals of the New York Academy of Sciences.
  10. ^ a b Chandrashekar J, Hoon MA, Ryba NJ, Zuker CS (2006). "The receptors and cells for mammalian taste". Nature. 444 (7117): 288–94. doi:10.1038/nature05401. PMID 17108952. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  11. ^ Beauchamp G (2009). "Sensory and receptor responses to umami: an overview of pioneering work". Am J Clin Nutr. 90 (3): 723S–7S. doi:10.3945/ajcn.2009.27462E. PMID 19571221. {{cite journal}}: Unknown parameter |month= ignored (help)
  12. ^ Yasuo T, Kusuhara Y, Yasumatsu K, Ninomiya Y (2008). "Multiple receptor systems for glutamate detection in the taste organ". Biological & Pharmaceutical Bulletin. 31 (10): 1833–7. doi:10.1248/bpb.31.1833. PMID 18827337. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  13. ^ Lehrer, Jonah (2007). Proust was a Neuroscientist. Mariner Books. ISBN 978-0-547-08590-6.
  14. ^ Smriga M, Mizukoshi T, Iwata D, Sachise E, Miyano H, Kimura T, Curtis R (2010). "Amino acids and minerals in ancient remnants of fish sauce (garum) sampled in the "Garum Shop" of Pompeii, Italy". Journal of Food Composition and Analysis. 23 (5): 442–446. doi:10.1016/j.jfca.2010.03.005. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  15. ^ Sweet, Sour, Salty, Bitter ... and Umami, NPR
  16. ^ Ikeda K (2002). "New seasonings". Chemical Senses. 27 (9): 847–9. doi:10.1093/chemse/27.9.847. PMID 12438213. {{cite journal}}: Unknown parameter |month= ignored (help) (partial translation of Ikeda, Kikunae (1909). "New Seasonings[japan.]". Journal of the Chemical Society of Tokyo. 30: 820–836.)
  17. ^ Kodama S (1913). Journal of the Chemical Society of Japan. 34: 751. {{cite journal}}: Missing or empty |title= (help)
  18. ^ Kuninaka A (1960). Journal of the Agricultural Chemical Society of Japan. 34: 487–492. {{cite journal}}: Missing or empty |title= (help)
  19. ^ a b Yamaguchi S (1998). "Basic properties of umami and its effects on food flavor". Food Reviews International. 14 (2&3): 139–176. doi:10.1080/87559129809541156.
  20. ^ Uneyama H, Kawai M, Sekine-Hayakawa Y, Torii K (2009). "Contribution of umami taste substances in human salivation during meal". Journal of Medical Investigation. 56 (supplement): 197–204. doi:10.2152/jmi.56.197. PMID 20224181. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  21. ^ Edmund Rolls (2009). "Functional neuroimaging of umami taste: what makes umami pleasant?". The American Journal of Clinical Nutrition. 90 (supplement): 804S–813S. doi:10.3945/ajcn.2009.27462R. PMID 19571217. {{cite journal}}: Unknown parameter |month= ignored (help)
  22. ^ Yamaguchi S, Takahashi; Takahashi, Chikahito (1984). "Interactions of monosodium glutamate and sodium chloride on saltiness and palatability of a clear soup". Journal of Food Science. 49: 82–85. doi:10.1111/j.1365-2621.1984.tb13675.x.
  23. ^ Roininen K, Lahteenmaki K, Tuorila H (1996). "Effect of umami taste on pleasentness of low salt soups during repeated testing". Physiology & Behavior. 60 (3): 953–958. PMID 8873274. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  24. ^ Yamamoto S, Tomoe M, Toyama K, Kawai M, Uneyama H (2009). "Can dietary supplementation of monosodium glutamate improve the health of the elderly?". Am J Clin Nutr. 90 (3): 844S–849S. doi:10.3945/ajcn.2009.27462X. PMID 19571225. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  25. ^ Ninomiya K (1998). "Natural Occurance". Food Reviews International. 14 (2&3): 177–211. doi:10.1080/87559129809541157.
  26. ^ Agostini C, Carratu B, Riva E, Sanzini E (2000). "Free amino acid content in standard infant formulas: comparison with human milk". Journal of American College of Nutrition. 19 (4): 434–438. PMID 10963461. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  27. ^ Chaudhari N, Landin AM, Roper SD (2000). "A metabotropic glutamate receptor variant functions as a taste receptor". Nature Neuroscience. 3 (2): 113–119. doi:10.1038/72053. PMID 10649565.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  28. ^ 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. {{cite journal}}: Unknown parameter |author-separator= ignored (help)
  29. ^ San Gabriel A, Uneyama H, Yoshie S, Torii K (2005). "Cloning and characterization of a novel mGluR1 variant from vallate papillae that functions as a receptor for L-glutamate stimuli". Chem Senses. 30 (Suppl): i25–i26. doi:10.1093/chemse/bjh095. PMID 15738140.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  30. ^ Kinnamon SC (2011). "Taste receptor signaling -from tongues to lungs". Acta Physiol: no–no. doi:10.1111/j.1748-1716.2011.02308.x. PMID 21481196.
  31. ^ Perez CA, Huang L, Rong M, Kozak JA, Preuss AK, Zhang H, Max M, Margolskee RF (2002). "A transient receptor potential channel expression in taste receptor cells". Nat Neurosci. 5 (11): 1169–76. doi:10.1038/nn952. PMID 12368808.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  32. ^ Zhang Y, Hoon MA, Chandrashekar J, Mueller KL, Cook B, Wu D, Zuker CS, Ryba NJ (2003). "Coding sweet, bitter, and umami tastes: different receptor cells sharing signaling pathways". Cell. 112 (3): 293–301. doi:10.1016/S0092-8674(03)00071-0. PMID 12581520.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  33. ^ Dando R, Roper SD (2009). "Cell-to-cell communication in intact taste buds through ATP asd signalling from pannexin 1 gap junction hemichannels". J Physiol. 587 (2): 5899–906. doi:10.1113/jphysiol.2009.180083.
  34. ^ Roper SD (2007). "Signal transduction and information processing in mammalian taste buds". Pflügers Archiv. 454 (5): 759–76. doi:10.1007/s00424-007-0247-x. PMID 17468883. {{cite journal}}: Unknown parameter |month= ignored (help)
  35. ^ Clapp TR, Yang R, Stoick CL, Kinnamon SC, Kinnamon JC (2004). "Morphologic characterization of rat taste receptor cells that express components of the phospholipase C signaling pathway". J Comp Neurol. 468 (3): 311–321. doi:10.1002/cne.10963. PMID 14681927.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  36. ^ Iwatsuki K, Ichikawa R, Hiasa M, Moriyama Y, Torii K, Uneyama H (2009). "Identification of the vesicular nucleotide transporter (VNUT) in taste cells". Biochem Bhiphys Res Commun. 388 (1): 1–5. doi:10.1016/j.bbrc.2009.07.069. PMID 19619506.{{cite journal}}: CS1 maint: multiple names: authors list (link)

References

  • Flavor Chemistry: Thirty Years of Progress By Roy Teranishi, Emily L. Wick, Irwin Hornstein; Article: Umami and Food Palatability, by Shizuko Yamaguchi and Kumiko Ninomiya. ISBN 0-306-46199-4
  • Barbot, Pascal; Matsuhisa, Nobu; and Mikuni, Kiyomi. Foreword by Heston Blumenthal. Dashi and Umami: The Heart of Japanese Cuisine. London: Eat-Japan / Cross Media, 2009

External links