EFFECT OF OXIDIZED DIETARY-LIPID AND VITAMIN-E ON THE COLOR STABILITYOF PORK CHOPS

The effect of oxidized corn oil and vitamin E (alpha-tocopheryl acetat e) in pig diets on the oxidative stability of muscle lipids and on the surface colour characteristics of fresh and previously frozen pork ch ops in refrigerated storage was investigated. Lipid oxidation (TBARS v alues) and surface redness (Hunter 'a' values) were significantly infl uenced (P < 0.01) by dietary alpha-tocopheryl acetate levels but not b y degree of oxidation of dietary corn oil. Lipid oxidation and colour deterioration during refrigerated storage were greater in previously f rozen chops compared to fresh chops. TBARS values were lower and Hunte r 'a' values higher in pork chops from pigs fed 100 and 200 mg alpha-t ocopheryl acetate/kg diet compared to pigs fed 10 mg/kg diet after 2, 4, 6 and 8 days of refrigerated storage. Hunter 'a' values were signif icantly correlated (P < 0.01) with the logarithm of TBARS values. The results suggest that oxidation of myoglobin precedes oxidation of musc le lipids in pork chops stored at 4-degrees-C