不同精炼脱酸方法对葡萄籽油中反式脂肪酸的影响研究

Effects of Different Deacidification Methods on the Trans Fatty Acids in the Grape Oil

本文以酸价为15．12±0．016mgKOH／g的葡萄籽毛油为原料，分别采用化学法、物理法和酶法精炼方法脱酸，重点研究了不同的精炼脱酸方法对葡萄籽油中反式脂肪酸的种类以及含量的影响，探讨了不同的精炼脱酸工艺申葡萄籽油的酸价以及反式脂肪酸含量的变化规律。采用化学法精炼脱酸，葡萄籽油的酸价降至0．10a±0．022mgKOH／g以下，反式脂肪酸含量增加了0．31±0．0011％。采用物理法精炼脱酸：在240℃条件下脱酸8h，酸价为0．13±0．018mgKOH／g，反式脂肪酸含量为1．86％。酶法酯化脱酸：在反应温度80℃、甘油添加量300％、加酶量3％、时间8h的条件下，葡萄籽油的酸价降到2．36士0．026mgKOH／g，反式脂肪酸含量由O．034±0．001％升至0．035±0．00l％0．041±0．0016％。不同的精炼脱酸方法对葡萄籽油中反式脂肪酸含量影响的规律为：酶法〈化学法〈物理法。采用酶促酯化脱酸方法对反式脂肪酸含量的影响很小。

Grape seed oil with acid value of 15.12±0.016 mg KOH/g, was used as raw material, and the effects of chemical, physical and enzymatic deacidification on the content and kind of trans fatty acids in the grape seed oil were investigated, The changes of trans fatty acids content and acid value in different refined technologies were discussed. The acid values were reduced to 0.10±0.022 mg KOH/g, while the content of trans fatty acids increased by 0.31±0.0011% when chemical refined was employed. The optimal conditions of physical deacidification of the grape seed oil were deacidification temperature 240 ℃ and time 8 h, under which the acid value of 0.13±0.018 mg K OH/g, and trans fatty acids content of 1.86% were obtained. The conditions of enzymatic esterification to deacidificate the grape seed oil were as follows： temperature 80 ℃, addition of glycerol 300% and enzyme 3% for 8 h. Under these conditions, the acid value declined to 2.36a：0.026 mg KOH/g, while the content of trans fatty acids increased fiom 0.034±0.001% to 0.035±0.001%-4）.041±0.0016%. Among the methods tested, the enzymatic esterification deacidifieation has the least influence on trans fatty acids content and followed by chemical refining.