PSYC 2390 Lecture Notes - Lecture 3: Anthocyanin, Flavonoid, Ferrous

• School: University of Guelph
• Department: Psychology
• Course: PSYC 2390
• Professor: Lana Trick

Document Summary

In the unoxygenated myoglobin exists in the reduced state, as ferrous (fe+2) iron. The ferrous myoglobin bind oxygen at the sixth binding site, and the oxygen becomes part of the pigment complex. This process is called oxygenation, which is distinct from oxidation. If exposure to oxygen continues, oxidation does take place, and production of metmyoglobin results. Metmyoglobin is associated with aged meat exposed to air and produces a grayish or brown meat colour. In nitrate-cured meats, myoglobin reacts with nitric oxide (no) to produce nitric oxide myoglobin, or nitrosylmyoglobin, which is bright pink-red. When cured meats are cooked, they retain the pinkish or reddish colour, due to the formation of nitrosohemochrome from denatured, coagulated nitrosylmyoglobin. Oxidation of the porphyrin ring can produce a yellow or green colour. In addition, the cholorophylls contain metal-coordinated porphyrin rings.