Antioxidative potential of tocotrienols and tocopherols in coconut fat at different oxidation temperatures

The objective of this study was to compare the stabilizing effects of tocotrienols and their corresponding tocopherols at 60 °C and 160 °C. Stability was determined in coconut fat by observing the Oil Stability Index (OSI), the peroxide value (POV) and conjugated dienes (CD). α- and β-tocotrienols as well as α-tocopherol induced susceptibility of the systems against oxidative deterioration and reduced the life time of coconut fat. δ- and γ-tocotrienols increased the fat's shelf-life at ambient temperature (60 °C). At frying conditions the antioxidative potential increased in the following order: α<γ<δ (Tocopherols) α<β500>100 (tocotrienols) and 5000 > 2000 > 1000 > 100 (tocopherols). Among the tested antioxidants δ-tocopherol and δ-tocotrienol were found to be most efficient against lipid oxidation both at 60 °C and at 160 °C. This study showed, that γ- and δ-tocotrienols, similar to the much better investigated tocopherols, are good food antioxidants to enhance shelf-life of coconut fat both at frying and at low temperature.