加速氧化过程中不同植物油的稳定性研究

Research on Stability of Different Plant Oils in the Process of Accelerated Oxidation

采用水酶法分别制备油茶籽油、花生油、核桃油、葵花油和大豆油,通过化学方法和中红外光谱技术对5种油脂在加速氧化过程中的稳定性进行研究。不同植物油的脂肪酸组成存在显著差异,油茶籽油和花生油的单不饱和脂肪酸含量大于多不饱和脂肪酸含量,而核桃油、葵花油和大豆油均含有大量的多不饱和脂肪酸,且含量均在50%以上。在整个加速氧化过程中,随着加热时间的延长,共轭二烯值和共轭三烯值逐渐增加。5种油脂的氧化稳定性由大到小依次为油茶籽油>花生油>核桃油>葵花油>大豆油。采用中红外光谱法对油脂氧化稳定性进行分析,再次印证了对共轭二烯值和共轭三烯值的分析结果。

The oxidative stability of camellia oil, peanut oil, walnut oil, sunflower oil and soybean oil prepared by aqueous enzymatic method was researched by chemical methods and mid-infrared spectra. Fatty acid composition in different plant oils had significant difference. The content of monounsaturated fatty acids in camellia oil and peanut oil was higher than that of polyunsaturated fatty acids, while walnut oil, sunflower oil and soybean oil contained large amounts of polyunsaturated fatty acids, which was more than 50%. In the process of the accelerated oxidation, conjugated diene value and conjugated triene value increased gradually with the extension of heating time. The order for oxidative stability of five kinds of oils was camellia oil>peanut oil>walnut oil>sunflower oil>soybean oil. The result of oils oxidative stability analyzed by mid-infrared spectra confirmed the analysis results of conjugated diene value and conjugated triene value once again.