The Effect of Dietary Fat and Tocopherol on Lipolysis and Oxidation in Turkey Meat Stored at Different Temperatures

Turkeys were fed diets containing tallow or soybean oil with either 5 or 60mg/kg all-rac-±-tocopherol for 9 weeks before slaughter. Muscle was sampled aseptically from breast or thigh and stored at 37, 4, or −18 C. Tocopherol tissue content reflected dietary levels; the fatty acid composition of muscle triglycerides was significantly affected by the dietary fat but that of phospholipids was influenced only slightly by the different diets. Both oxidative and lipolytic changes were greater in leg muscle than in breast muscle. High dietary tocopherol levels resulted in decreased oxidation on storage of meat tissues as did feeding of a more saturated fat diet. Diets did not influence the rate of hydrolysis of phospholipids, but differences in the free fatty acid concentrations were found, presumably due to increased oxidation in the soybean oil, low tocopherol diet. The concentration of conjugable oxidation products was directly correlated with initial polyunsaturated fatty acid concentrations and inversely with tocopherol concentrations.