生育酚与生育三烯酚在油脂中稳定性研究

Study on stability of tocopherols and tocotrienols in oil

为研究油脂中生育酚(tocopherols,T)与生育三烯酚(tocotrienols,T_3)在高温和加速氧化条件下的稳定性,使用棕榈油、大豆油和小麦胚芽油配制成含有8种生育酚与生育三烯酚的调和油。测试棕榈调和油脂中生育酚与生育三烯酚在100℃、150℃、180℃和200℃的热稳定性,并使用Rancimat仪测试生育酚与生育三烯酚在25℃、100℃、110℃、120℃下的加速氧化稳定性。结果表明:随着温度的升高和时间的增加,生育酚与生育三烯酚的损失率变大,在150℃以上高温氧化时8种生育酚与生育三烯酚损失率排序为δ-T<β-T<α-T<γ-T<δ-T_3<β-T_3<α-T_3<γ-T_3。100℃高温氧化及100℃、110℃、120℃加速氧化条件下,8种生育酚与生育三烯酚的损失率顺序为δ-T<δ-T_3<γ-T<β-T<γ-T_3<β-T_3<α-T<α-T_3。在25℃加速氧化6 h,生育酚与生育三烯酚几乎无损失,而在100℃、110℃下加速氧化6 h,生育酚与生育三烯酚的总损失率分别为45.25%、97.32%,说明油脂中生育酚与生育三烯酚在低温下加速氧化时稳定性较好,温度大于100℃后,加速氧化时损失速度明显加快。本研究为减少油脂中生育酚与生育三烯酚的损失提供参考。

In order to study on stability of tocopherols（T）and tocotrienols（T_3）in oil under the condition of high temperature and accelerated oxidation,the blended oil which is rich in 8 tocopherols and tocotrienols was made by palm oil,soybean oil and wheat germ oil,thermal stability of tocopherols and tocotrienols at 100℃,150℃,200℃ and accelerated oxidative stability at 25℃,100℃,110℃,120℃ were analyzed.The results showed that the loss of tocopherols and tocotrienols increased with rising temperature and increasing time,the order of tocopherols and tocotrienols loss in blended oil wasδ-Tβ-Tα-Tγ-Tδ-T_3β-T_3α-T_3γ-T_3,when the temperature was above 150℃,the total loss rate of tocopherols and tocotrienols was 29.81%,24.17%,31.58%,21.19% at 100℃ for 96 h,150℃ for 24 h,180℃ for 16 h,200℃ for 8 h,respectively.The loss order turned intoδ-Tδ-T_3γ-Tβ-Tγ-T_3β-T_3α-Tα-T_3 when the temperature was below 120℃,the total loss rate was almost 0%at 25℃ for 6 h,and increased to 45.25%,97.32% at 100℃,110℃,respectively.So the tocopherols and tocotrienols in oil had good oxidative stability at low temperatures,the loss rate increased rapidly in accelerated oxidation when the temperature was above 100℃.This study provides information for less loss of tocopherols and tocotrienols in oils.