Q What is the difference between light and dark meat?
A "Dark muscles, because they're locomotive, are a different fiber type than light muscles, and the fibers contain different amounts of oxygen-carrying proteins," said poultry expert Mark Richards, a professor of animal sciences at UW–Madison.
Dark meat gets its color from relatively high levels of iron-containing oxygen-transport proteins, including myoglobin and hemoglobin. They are needed to supply the large amounts of oxygen demanded by muscles involved in sustained activity, such as leg muscles.
In contrast, muscles used for quick bursts of energy, such as turkey and chicken breast muscles, have smaller oxygen needs, lower levels of oxygen-transport proteins and thus a lighter color.
Nutritionally there isn't as much difference between the two as many people think, Richards said.
Breast meat has slightly fewer calories per ounce due to higher protein and lower fat content — approximately 4 grams of fat in a 3.5 ounce serving of turkey breast compared to 7 grams in turkey thigh. But that extra fat in the dark meat makes it juicier and contributes to a pleasing mouthfeel, much like marbling in steak, he added.
— Provided in cooperation with University Communications