α-及γ-生育酚对玉米油回色的影响

Effect of α-and γ-Tocopherols on Color Reversion of Corn Oil

为了研究不同生育酚异构体对油脂回色的影响,分别将α-生育酚、γ-生育酚及α-和γ-生育酚添加到中链脂肪酸甘油酯(MCT)和玉米油甘油三酯中,通过105℃烘箱加热10 h来考察回色情况。结果表明,在MCT和玉米油三酰甘油中,虽然α-生育酚损失量远大于γ-生育酚,但微小的γ-生育酚的变化对油脂回色的影响却更显著。加热之后,玉米油甘油三酯中生育酚的损失量大于MCT中的损失量。尽管α-生育酚单独存在的情况下对玉米油的回色几乎没有影响,但当α-及γ-生育酚共同存在的情况下,α-生育酚对γ-生育酚引起的玉米油的回色起到抑制作用。

To make a research on the effect of tocopherols isomer on color reversion of oils and fats, model studies were conducted by adding α- tocopherol, γ- tocopherol and the mixture of α - and γ- tocopherol tocopherols into medium chain triacylglycerol （MCT） and corn oil triglyceride. The model system was heated at 105℃ for 10 h for observing the status of color reversion. The reduction of α - tocopherol was found much higher than that of γ- tocopherol in the MCT and corn oil triglyceride. However, slight change of γ - tocopherol was found to contribute more to color reversion of both MCT and corn oil. After heating, the corn oil triglyceride consumed more tocopherols and was more darkened than the MCT oil. Although α - tocopheroldid did not affect darkening of the corn oil triglyceride, it was found to restrain color reversion of corn oil when it existed together with γ- tocopherol.