热重分析法在油脂氧化稳定性研究中的应用

Application of thermogravimetric analytical method in the research on oxidation stability of oils and fats

主要介绍了热重分析法在食用油脂氧化稳定性定性分析中的应用,检测了菜籽油、玉米油、调和油3种油脂的氧化分解温度,探讨了升温速率、保护气氛对油脂氧化分解温度的影响;通过油脂的热重分析法等温实验,观察了油脂的氧化诱导时间。实验表明:菜籽油的氧化稳定性优于玉米油和调和油;相同条件下,升温速率越快,氧化分解温度越高;在氮气气氛下,油脂的氧化稳定性更好。热重分析方法采样量少、操作方便、效果明显,可以应用于油脂生产过程的质量监控和抗氧化剂的开发研究。

A thermogravimetric analytical （TGA） method was introduced to research the oxidation stability of edible oils, and the decomposition temperatures of rapeseed oil, corn oil, blend oil were detected by the method. The effects of the heating rates and the protective atmosphere on the decomposition tempera- tures were discussed. By the isothermal process, the oxidation induction time was obtained. The results showed that the rapeseed oil had the best oxidation stability among the three kinds of oils. Under the same conditions, the faster the rising rate was, the higher the decomposition temperature was. In nitro- gen, the oil was steadier than that in air and oxygen. TGA method had the advantages of less sampling, convenient operations and obvious effects, and it could be used in quality control during oil production process, and study on development of various antioxidants.