What pigment is responsible for the color in meats, particularly contributing to a dark purplish hue in beef?

The pigment responsible for the color in meats, specifically contributing to a dark purplish hue in beef, is myoglobin. Myoglobin is a protein found in muscle tissue that binds oxygen and stores it for use during muscle activity. This storage function is particularly important in muscles that are used more frequently, such as those in mammals, leading to a higher concentration of myoglobin in red meats like beef.

The purplish hue of fresh beef is due to the reduced form of myoglobin, known as deoxymyoglobin. When meat is exposed to oxygen, myoglobin can oxidize to form oxymyoglobin, which gives the meat a bright red color, whereas its reduced state imparts the darker purplish shade.

On the other hand, hemoglobin is the oxygen-carrying protein in blood and is not primarily responsible for the color of muscle tissue. Carotene is a plant pigment that imparts orange and yellow colors, while chlorophyll is responsible for the green color in plants. Neither of these pigments plays a significant role in the coloring of meat. Therefore, myoglobin is specifically recognized for its role in providing the distinct color characteristic of muscle meats.