植物油加热过程中品质及反式脂肪酸的变化

Variation of Quality and Trans Fatty Acids in Edible Oil during Heating

以大豆油、稻米油和玉米油为原料,均分别加热至180℃,220℃和260℃后,取0.5,1,2,4,6,8和10 h的油样,并且在24 h后再次复热至180℃,220℃和260℃,取复热油样及复热后0.5,1和2 h油样,测定油样酸价及其反式脂肪酸的变化。结果发现,随温度升高,酸价有明显上升的趋势,相对而言,稻米油的酸价偏高。反式脂肪酸有上升趋势,主要体现在260℃时,上升十分明显。综合考虑,大豆油在烹调温度下反式脂肪酸产生相对较少,酸价指标适合,更适合作为家庭用油。

With soybean oil, rice oil, com oil as experiment material, heated to 180 ℃, 220 ℃, and 260 ℃, after heating temperature reached 0.5, 1, 2, 4, 6, 8, and 10 h sampling, after 24 h heat to 180 %, 220 ℃, and 260 ℃, take after thermal sample and after 0.5, 1, and 2 h sample, determining oil acid value （AV） and fatty acids. The results show that with the temperature rise, acid value have obvious rising trend, saturated fat and monounsaturated fatty acids have a rising trend, and polyunsaturated fatty acids have a downward trend; Comprehensive consideration, soybean oil in cooking temperature trans fatty acids is relatively small, more suitable for oil as a family.