In order to study on stability of tocopherols (T) and tocotrienols (T3) 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 was δ-T ＜ β-T ＜ α-T ＜ γ-T ＜ δ-T3 ＜ β-T3 ＜ α-T3 ＜ γ-T3,when the temperature was above 150 ℃,the total loss rate of tocopherols and tocotdenols 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 into δ-T ＜ δ-T3 ＜ ~T ＜ β-T ＜ γr-T3 ＜ β-T3 ＜ α-T ＜ α-T3 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 tocotdenols 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.%为研究油脂中生育酚(tocopherols,T)与生育三烯酚(tocotrienols,T3)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-T3＜β-T3＜α-T3＜γ-T3.100℃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-T3＜γ-T＜β-T＜γ-T3＜β-T3＜α-T＜α-T3.在25℃加速氧化6h,生育酚与生育三烯酚几乎无损失,而在100℃、110℃下加速氧化6h,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.
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