The effect of DFD classification and internal cooking temperature on certain pork muscle characteristics

The data incorporated in this experiment were gathered from 14 littermate pairs of swine of the same sex differing in weight by <4·5 kg with one animal in each pair subjected to standardized stress. Samples of the Longissimus dorsi (LD) and the Psoas major (PM) muscles were cooked to internal temperatures of 64, 70 and 76°C. The samples of the Quadriceps femoris (QF) muscle were cooked to internal temperatures of 70 and 76°C. DFD classification of the raw muscle was determined by the 48 h pH. Stress produced DFD meat in the PM and QF muscles but not in the LD muscle. DFD muscle required shorter time to reach any of the cooked internal temperatures studied when compared to normal muscle. Slightly-DFD PM muscle more closely resembled the normal muscle in all variables except the panel tenderness score. Cooking DFD PM muscle to an internal temperature 6°C higher than normal muscle caused a reverse in the direction of cooking loss, fiber diameter, tenderness and expressible water when compared to normal and DFD muscle cooked to the same internal temperature. Cooking DFD PM muscle to an internal temperature 12°C higher than normal muscle produced changes associated with increasing the internal temperature of normal muscle. Similar trends, as described for the PM muscle, were observed in the QF muscle.