Metmyoglobin is the oxidized form of the oxygen-carrying hemeproteinmyoglobin. Metmyoglobin is the cause of the characteristic brown colouration of meat that occurs as it ages.
In living muscle, the concentration of metmyoglobin is vanishingly small, due to the presence of the enzyme metmyoglobin reductase, which, in the presence of the cofactorNADH and the coenzymecytochrome b4 converts the Fe3+ in the heme prosthetic group of metmyoglobin back to the Fe2+ of normal myoglobin. In meat, which is dead muscle, the normal processes of removing metmyoglobin are prevented from effecting this repair, or alternatively the rate of metmyoglobin formation exceeds their capacity, so that there is a net accumulation of metmyoglobin as the meat ages.
[1] Metmyoglobin reduction helps limit the oxidation of myoglobin and the oxidation of myoglobin is specific to each species. In other words, metmyoglobin gains electrons in order to limit myoglobin from losing electrons. Metmyoglobin after being oxidized by myoglobin shows the undesirable brown color which can be seen in many types of meat. Metmyoglobin is more susceptible to oxidation when being compared to oxymyoglobin.[2] The metmyoglobin reducing activity varies across species and was studied particularly in beef, porcine, bison, deer, emu, equine, goats and sheep.
[3] Currently there is not a standard technique in measuring the metmyoglobin in all species. But many techniques are used including reflectance spectrophotometry and absorbance spectrophotometry are used.
metmyoglobin, oxidized, form, oxygen, carrying, hemeprotein, myoglobin, cause, characteristic, brown, colouration, meat, that, occurs, ages, living, muscle, concentration, metmyoglobin, vanishingly, small, presence, enzyme, metmyoglobin, reductase, which, pres. Metmyoglobin is the oxidized form of the oxygen carrying hemeprotein myoglobin Metmyoglobin is the cause of the characteristic brown colouration of meat that occurs as it ages In living muscle the concentration of metmyoglobin is vanishingly small due to the presence of the enzyme metmyoglobin reductase which in the presence of the cofactor NADH and the coenzyme cytochrome b4 converts the Fe3 in the heme prosthetic group of metmyoglobin back to the Fe2 of normal myoglobin In meat which is dead muscle the normal processes of removing metmyoglobin are prevented from effecting this repair or alternatively the rate of metmyoglobin formation exceeds their capacity so that there is a net accumulation of metmyoglobin as the meat ages 1 Metmyoglobin reduction helps limit the oxidation of myoglobin and the oxidation of myoglobin is specific to each species In other words metmyoglobin gains electrons in order to limit myoglobin from losing electrons Metmyoglobin after being oxidized by myoglobin shows the undesirable brown color which can be seen in many types of meat Metmyoglobin is more susceptible to oxidation when being compared to oxymyoglobin 2 The metmyoglobin reducing activity varies across species and was studied particularly in beef porcine bison deer emu equine goats and sheep 3 Currently there is not a standard technique in measuring the metmyoglobin in all species But many techniques are used including reflectance spectrophotometry and absorbance spectrophotometry are used References edit Bechtold Emily Suman Surendranath Mohanty Smita Mazumder Suman Krishnan Sadagopan Nerimetla Raja July 2019 46 Species specificity in metmyoglobin reduction Journal of Animal Science 97 Suppl 1 83 84 doi 10 1093 jas skz053 191 ISSN 0021 8812 PMC 6663687 Metmyoglobin an overview ScienceDirect Topics www sciencedirect com Retrieved 2022 05 17 Bekhit A E D Faustman C 2005 11 01 Metmyoglobin reducing activity Meat Science 71 3 407 439 doi 10 1016 j meatsci 2005 04 032 ISSN 0309 1740 PMID 22060917 External links editMetmyoglobin at the U S National Library of Medicine Medical Subject Headings MeSH nbsp This protein related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Metmyoglobin amp oldid 1120458677, wikipedia, wiki, book, books, library,
