2013 Volume 19 Issue 6 Pages 1127-1131
Tocopherols and phytosterols were added to medium chain triacylglycerol (MCT) to study their effect on color reversion of vegetable oils. Four samples with 0, 6,000, 10,000 and 14,000 mg/kg phytosterols were heated at 105°C for 12 h. No significant reduction of phytosterols and obvious color change were found in the four samples. Five samples with 0, 1,000, 2,000, 5,000, 10,000 mg/kg tocopherols were also heated at 105°C for 12 h. About 2 − 5% tocopherols were absent after heating. Reduction of total tocopherol was found linearly related to color darkening. The most significant reduction is α-tocopherol. Reduction of α-tocopherol correlated more with color darkening than that of γ-tocopherol. The conclusion is phytosterol has no effect on color reversion of oils and reduction of α-tocopherol was attributed to be the most important cause of color reversion.