The color of beef when freshly cut is a dark red. This changes to a bright red when the meat is exposed to oxygen. The change in color from purplish red to bright red is reversible. With prolonged exposure to oxygen, the pigment is oxidized and loses its bright red color. Veal, too young to have accumulated as much pigment as the older beef animals, is grayish-pink and the bones have a pinkish tinge. The lean of lamb is a darker, deeper red than beef. The paler pink of fresh pork have less myoglobin. The fat of pork with its higher unsaturated fatty acid content is much softer than that from either beef or lamb.