稻米油高温加热脂肪酸的形成和变化

Heating at High Temperature for a Long Time the Formation and Change of Edible Oiltrans Fatty Acids

对稻米油进行加热试验，通过研究不同加热温度（180℃，220℃和260℃）、不同加热时间（0．5-10h）以及隔夜后（0．5，1和2h）脂肪酸的组成变化。研究表明，稻米油在180℃时反式脂肪酸的含量基本上没有变化，180℃加热10h后放置一夜，再次复热的油脂中反式脂肪酸的含量也没有明显的增加，但如果在更高的温度，隔夜复热2h后，油脂中会产生约是原油12倍的反式脂肪酸。180℃时，随着加热时间的延长，亚油酸和亚麻酸都有适度的降低，但降低的量还微乎其微。随着温度不断的上升，当温度达到260℃的时候，亚油酸降低了约原油的17倍，而亚麻酸基本上已经无法检测出。

Heating experiments on rice oil, the temperature of heat （ 180 ℃, 220 ℃ and 260 ℃）, different heating time （0.5-10 h） and after overnight （0.5, 1 and 2 h） changed in the composition of fatty acids were studied. The resulf showed that at 180℃ for long time heating, rice oil trans fatty acids did not change; With the heating time, linoleic acid and linolenic acid were moderately reduced; Overnight, once again hot oil in the content of trans fatty acids was not obviously increased. At a higher temperature, the overnight complex after thermal 2 h, oil produce about 12 times Irans fat oil, linoleic acid reduces about 17 times of crude oil, and flax acid basically even cannot detected.