Effects of dietary organic selenium and vitamin E supplementation on post mortem oxidative deterioration in muscles of pigs

The effect of feeding high levels of alpha -tocopherol and organic selenium (Se) to pigs on colour stability and on the susceptibility to oxidative deterioration was investigated. Treatments consisted of supplementation of vitamin E (200 mg/kg diet), organic Se (0.3 mg/kg diet) and both vitamin E and organic Se for the last 60 days to finishing pigs before slaughtering. Longissimus dorsi (LD) and psoas major (PM) muscles were examined after 2 and 7 days of storage on colour stability and on lipid peroxidation (measured as malondialdehyde equivalents). Rate of oxidation by stimulation with Fe2+/ascorbate was also estimated in LD samples obtained post mortem. In PM 7 days post mortem we found differences between control and groups of pigs supplemented with vitamin E and Se on reflectance, but significant differences (P<0.05) were found only in the vitamin E + Se group. Positive effects (P<0.05) of vitamin E and Se on colour in psoas major muscle refrigerated for 7 days are supported with significant (P<0.05) lower levels of TBARS values in pigs supplemented with vitamin E and organic Se as well. Supplementation with organic Se does not affect the oxidative stability of muscle tissue (longissimu dorsi) when the rate of iron-induced lipid oxidation was examined. Dietary Se had limited potential for enhancing the quality of pork carcasses (psoas major) and accentuating the effect of vitamin E on the oxidative stability of longissimus dorsi muscle was not found.