Effect of Adrenaline Stress on Pork Quality

Abstract
Sixteen Hampshire hogs were used to determine the effect of preslaughter adrenaline injections on subsequent muscle characteristics. Injection of adrenaline significantly reduced liver and muscle glycogen. Initial pH values at 30 min. post-mortem of longissimus dorsi and semimembranosus muscles of the treated hogs were higher and the subsequent changes less rapid than non-treated muscles. Ultimate pH of the longissimus dorsi, semimembranosus, gluteus medius, gluteus accessorius, transversus abdominus and psoas major muscles from adrenaline-treated animals was significantly higher than from non-treated animals. The color of prepackaged loin chops from adrenaline-treated hogs was more stable and more desirable during 11 days display at 38° F. than that of chops from non-treated hogs. Although not significant, color of prepackaged cured ham slices from the adrenaline-treated hogs was also slightly more desirable during 8 days display. Flavor and tenderness of loin chops from adrenaline-treated animals were as desirable as that of chops from non-treated animals. Bacterial growth during storage of prepackaged loin chops and cured ham slices was enhanced by the lower acidity of muscle tissue from the adrenaline-treated animals. Copyright © 1964. American Society of Animal Science . Copyright 1964 by American Society of Animal Science