The relationship between muscle α-tocopherol concentration and meat oxidation in light lambs fed vitamin E supplements prior to slaughter .
BACKGROUND: The use of concentrates supplemented with alpha-tocopherol in animals is an effective method to reduce the oxidative processes that occur in meat products. The high cost of alpha-tocopherol requires accurate feeding, so it is necessary to define the minimum period of alpha-tocopherol concentrate supplementation that will ensure an acceptable meat quality. Indoor concentrate-fed light lambs (n=35)were supplementedwith 500mgDL-alpha-tocopheryl acetate (VE) kg−1 concentrate for a period of between 4 and 28 days before being slaughtered at 22–24 kg body weight. Control lambs (n = 12) were not supplemented with alpha-tocopherol.
RESULTS: The alpha-tocopherol content in both plasma and muscle tissues increased significantly with the length of supplementation (P < 0.001). The thiobarbituric acid-reactive substance (TBARS) concentration in meat decreased exponentially when the muscle alpha-tocopherol concentration was increased to 0.61–0.90mg kg−1 fresh meat (P < 0.05). After 7 days of display, the formation of metmyoglobin (MMb) decreased significantly as the alpha-tocopherol content increased to 0.31–0.60mg kg−1 meat (P < 0.05).
CONCLUSION: A range of 0.61–0.90mg alpha-tocopherol kg−1 freshmeat protected fresh lambmeat fromlipid oxidation and MMb formation. This level can be achieved by supplementation with 500mg VE kg−1 concentrate for a period of 7–14 days before slaughter.