Influence Of Vitamin E And Selenium On The Oxidative Stability Of Beef During The Maturation And Storage

Two experiments were included in this study: In experiment one, twenty four 500-600 kg Qin-chuan steers were selected arid divided into four groups by virtue of body weight and assigned randomly to one of four dietary treatments for three months. i.e. two levels of dl- a -tocopheryl acetate (30 and 500 IU day?steer? and two levels of selenium (0.30 and 0.60 mg selenium, as sodium selenite, per kilogram feed). The results were showed that : (1) The concentrations of a -tocopherol in plasma and gluteus medius (GM) were elevated (pO.O5) in u -tocopherol concentrations between the different treatments of selenium; (2) To some extend, selenium concentrations in tissues increased as the level of selenium in the diet rose, Se Concentration in plasma from the groups fed the diet with 0.60 ppm selenium was higher (p0.05) between the treatments of 0.30 and 0.60 ppm Se; (3) Compared with it from 30 IU vitamin E supplementation day?steer the susceptibility to lipid oxidation in GM during the aging and storage was reduced (pO.O5); (4) Under the same level of vitamin E supplementation, no statistically significant difference in TBARS value, color stability and drip loss between two treatments of 0.30 and 0.60 ppm Se was founded (p>O.O5). In experiment two, twenty 420-500 kg Jin-nan steers were selected and divided into five groups in the light of body weight. Steers were allotted to a 2 X 2 factorial experiment with two levels of dl- a -tocopheryl acetate (0 and 1000 IU day?steer? and two levels of selenium (0.10 and 0.40 ppm). A basal diet (VEOSeO) without the addition of vitamin E and selenium was added to the experimental design, giving a total of 5 dietary treatments. The results were demonstrated that : (1) No statistically significant difference between dietary treatments was obtained with regard to average day gain, dressing percentage, cooking loss, the contents of intramuscular fat and moisture in GM (p>O.O5); (2) a -tocopherol concentrations in plasma and GM were enhanced (pO.OS) by selenium supplementation ; (3) To some extend, selenium concentrations in tissues increased as the level of selenium in the diet rose, Se concentration in blood and GM from the treatment of 0.40 mg selenium per kilogram diet was higher (pO.OS) by dietary treatments; (5) The levels of GPx activity remained constant from day 3 to day 14 during the maturation, but on day 9, the levels of SOD activity decreased (pO.O5); (7) Although the levels of GPx activity rose with increasing dietary selenium , the increased activities of GPx did not hinder lipid oxidation (p>O.O5); (8) Under the same lev...