The chemistry of pigments in cooked meat depends on the predominant
redox form of Mb in raw meat before the cooking begins. Therefore,
factors governing the chemistry of pigments and color in fresh
meat profoundly affect the color of cooked meat as well. Exposure to
heat (during cooking/thermal processing) leads to the unfolding (denaturation)
of the globin portion ofMb and results in a concomitant exposure
of heme group to the external environment. The exposed heme
moiety is more susceptible to oxidation than the heme in its native
state. One result of the heat-induced denaturation of globin is that pigments
in cooked meats coagulate and become insoluble in water/
buffers (Tappel, 1957; Cornforth, 2001). Therefore, reflectance measurements
must be used to study cooked meat pigments, while absorbance
spectrophotometry is widely used to study fresh meat pigments