Oxidative stability of soybean triacylglycerol using carotenoids and y-tocopherol

Abstract

The effect of lycopene, β-carotene, and γ-tocopherol on the oxidative stability of soybean triacylglycerol was evaluated under Schaal oven conditions at 60°C. Peroxide value, conjugated diene, hydroperoxides, and thiobarbituric acid reactive substances were used as indicators for primary and secondary lipid oxidation products, whereas Rancimat method was used to study the oil stability. Results indicated that lycopene and β-carotene acted as pro-oxidants, whereas γ-tocopherol acted as antioxidant in triacylglycerol. Pro-oxidative activity of lycopene was higher than β-carotene at 100 and 200 ppm levels under Schaal oven thermal conditions. The combination of lycopene and γ-tocopherol (1:2) acted as antioxidant with better efficiency than γ-tocopherol alone in inhibiting the hydroperoxide formation in triacylglycerols.