Antioxidant, lipolytic and proteolytic enzyme activities in pork meat from different genotypes

Oxidative processes in meat lead to meat quality deterioration. Meat has endogenous antioxidants and prooxidants, but information on factors influencing the activity of antioxidant enzymes in meat is limited. Lipolytic and proteolytic enzymes are involved in important aspects of meat quality. Our objective was to find differences between five different genotypes on the activity of antioxidant, lipolytic and proteolytic enzymes in me-at. Forty Psoas major muscles of females of five different pig genotypes were used, Pietrain. Landrace, Large-White, Iberian, and lberian x Duroc. Pre slaughter conditions were similar for all the genotypes. After slaughter, muscles were vacuum packed and frozen at -20 degreesC until required. Differences between genotypes were found for the activity of catalase and SOD, while GSH-Px showed no differences. The highest differences between breeds were found for the Iberian breed where catalase had the highest activity. Catalase activity also showed differences between the white pigs, with large values for LR and lower activities in P. There were no differences in neutral lipase activities between the different genotypes while acid lipase and phospholipase showed significant differences. The activities of cathepsin B and H were significantly lower for Iberian pigs compared with other breeds except LR, while the ratio of cathepsin B + L/cathepsin B was higher in Iberian. The differences between genotypes found in enzyme activities suggest some genetic effects on the antioxidant, lipolytic and proteolityfic activity of pork meat. (C) 2003 Elsevier Ltd. All rights reserved.