Influence of dietary vitamin E supplementation on antioxidative status in muscle and meat quality of pigs

The effect of feeding a high level of vitamin E on the antioxidative status of longissimus dorsi muscle and meat quality of pigs was investigated, Treatments consisted of supplementation of vitamin E (200 mg/kg diet) for the last 60 days to finishing pigs before slaughtering. Longissimus dorsi (LD) muscle was examined after 2 and 5 days of storage for colour (reflectance), drip loss and shear force. alpha -Tocopherol level, total protein, intramuscular fat and pH (45 min post mortem) were also determined. Lipid peroxidation (thiobarbituric acid reactive substances - TBARS - measured as malondialdehyde equivalents) in 5 and 6 days after thawing of muscle samples and rate of oxidation by stimulation with Fe2+/ascorbate were estimated in LD samples. alpha -Tocopherol level was higher (P < 0.05) in LD from pigs treated with higher vitamin E than in controls (1.71 vs. 2.73 mg/kg). There were observed tendencies to lower drip losses and higher shear force in LD pigs supplemented with vitamin E. Inhibition of TBARS during storage (frozen and thawed) and rate of oxidation were positively influenced by vitamin supplementation. We concluded that dietary vitamin E supplementation (200 mg/kg diet) to pigs during the last 60 days of finishing increases the <alpha>-tocopherol concentration of tissue, reduces lipid peroxidation and improves the antioxidative status of muscle tissue.