Effects of dietary vitamin E supplementation on α-tocopherol content and antioxidative status of beef muscles

The effect of feeding a high level of vitamin E on the level of alpha-tocopherol in muscle tissue and on the antioxidative status of longissimus thoracis (LT) and psoas major (PM) of bulls (Slovak Pied, n = 16) was investigated. Treatments (n = 8) consisted in supplementation of vitamin E (1 000 mg alpha-tocopherol acetate/head/day) for the last 100 days before slaughter (average 540 kg live weight). Concentration of alpha-tocopherol was estimated from ante-mortem biopsy (taken before slaughter) samples of m. semitendinosus (ST) and post-mortem samples of LT and PM. Total protein, total water, intramuscular fat, total pigments; pH 48 h post-mortem and rate of oxidation by stimulation with Fe2+/ascorbate were estimated in LT and PM muscles. The level of alpha-tocopherol was higher (P < 0.05) in muscles, (LT, PM and ST) from bulls treated with higher vitamin E than in controls in the order PM > ST > LT The level of alpha-tocopherol can be controlled also ante-mortem (ST muscle). The rate of oxidation was positively influenced by vitamin E supplementation in the order PM > LT We concluded that dietary vitamin E supplementation (1000 mg alpha-tocopherol acetate/head/day) for the last 100 days to finishing bulls increases alpha-tocopherol concentrations in muscle and improves the antioxidative status of muscle tissue.