Estimation of α-tocopherol concentration necessary to optimise lamb meat quality stability during storage in high-oxygen modified atmosphere using broken-line regression analysis

The research was carried out to evaluate the effect of different a-tocopherol concentrations in lamb meat on oxidative stability during storage in high-oxygen atmosphere. Thirty-six lambs were randomly distributed to four groups and given diets containing four levels of vitamin E (20, 270, 520 and 1020 mg vitamin E/kg feed) from an initial weight of 13.2 +/- 0.5 kg to a slaughter weight of 26.2 +/- 0.3 kg. Supplementation of the diet with vitamin E increased (P < 0.001) the concentration of alpha-tocopherol in the meat and concentrations were obtained in the 0.46 to 4.14 mg/kg meat range. Broken-line analysis of data indicated a target dietary vitamin E supplementation of 287 mg/kg feed, which corresponded with a concentration of 2.26 mg alpha-tocopherol/kg meat. alpha-Tocopherol in meat was highly correlated with the oxidation of lipids and pigments. Broken-line analysis of data indicated the target alpha-tocopherol concentration in lamb for improved protection against lipid and pigment oxidation during 14, 21 and 28 days of storage in high-oxygen atmosphere was in the range 1.87 to 2.37 mg/kg meat. These concentrations of alpha-tocopherol in the meat made it possible to maintain the indicator values of lipid and pigment oxidation below the values considered in the bibliography as unacceptable to the consumer