Effects of dietary selenium and vitamin E on the oxidative stability of lard

Abstract

The effects of dietary sodium-selenite and Vitamin E on the oxidative stability and fatty acid composition of lard have been investigated. Lard samples were subjected to the accelerated storage at 60 degrees C in classic oven test. The level of lipid peroxidation was analyzed by measuring the thiobarbituric acid reactive substances and peroxide production, as well as the decrease in a polyunsaturated fatty acid levels. The fatty acid composition of lard was not influenced by dietary factors and prolonged heating. Supplementing the diets with tocopherol-acetate (30 mg kg(-1) of feed) significantly increased the oxidative stability of lards during heating and the protective effect of vitamin E was comparable with that of butylated hydroxytoluene (BHT). Dietary selenium (0.3 mg kg(-1) of feed as sodium-selenite) was not effective as an antioxidant in lards. The combination of dietary vitamin E and sodium-selenite showed significant protective effect against peroxidation in lards in comparison to the control group, deficient both in vitamin E and selenium, but this combination was significantly less effective than dietary vitamin E alone.