What causes meat to be a particular color?
Myoglobin, a protein, is responsible for the majority of the red color in red muscle tissue. Myoglobin is fixed in muscle cells and in its native form it is purple-red in color. When muscle tissue is cut or ground so that it is exposed to air (oxygen), the myoglobin becomes oxymyoglobin and turns a bright, cherry-red color. This is the color of much of the meat that we buy in the grocery store. Exposure of muscle tissue to oxygen for a prolonged period of time further changes the color. The muscle is no longer a bright, cherry-red color, but becomes a brown-red, and the pigment is then known as metmyoglobin. Consumers often associate this brown-red color with meat that is spoiled. Other changes take place to the color of uncured meat as it is cooked; the meat changes to a gray-brown. Does a change in meat color indicate spoilage? Change in color alone does not mean that meat is spoiled. Color changes are normal for fresh product. Fresh meat can remain a purple-red color if vacuum packa
