Myoglobin is the pigment responsible for giving meat its dark red color and more pronounced flavor. The color will vary depending on the amount of myoglobin present in the muscle tissue. Myoglobin helps transport oxygen to working muscles, so the more exercise a particular muscle gets, the more myoglobin present and therefore, the darker the meat. An animal’s diet, age, sex, species and the amount of exercise it gets will all contribute to the amount of myoglobin present.

Slow cooking at low temperatures helps to maintain the color of dark meat. At low temperatures, myoglobin tends to denature less quickly, so the meat maintains its pink or red pigments even though the meat is fully cooked through. Cooking meat at high temperatures causes myoglobin to denature rapidly, which turns the meat gray.

The meat of beef and lamb tend to be very red in comparison to pork and chicken.