袁野等

摘要 [目的]从大豆油脱臭馏出物中高效分离出饱和脂肪酸。[方法]试验采用低温协同超高压脲包法，以棕榈酸乙酯的残留率和质量为主要考察指标，通过单因素试验考察了冷藏温度、冷藏时间和超高压处理压力3个因素对分离效果的影响，并以正交试验法对该工艺进行了优化。[结果]试验表明，低温协同超高压脲包法分离大豆油脱臭馏出物的最佳工艺条件为冷藏温度4 ℃，冷藏时间90 min，压力300 MPa。在此条件下，棕榈酸乙酯的残留率为21.87%，质量从137.31 g减少到30.03 g。[结论]经过低温冷藏处理后，采用超高压脲包法可有效分离出大豆油馏出物中的饱和脂肪酸，为进一步的分离纯化创造了良好条件。

关键词 超高压脲包；低温协同；大豆油脱臭馏出物；正交试验

中图分类号 S509.9 文献标识码 A 文章编号 0517-6611（2014）03-00882-04

Abstract [Objective] To separate saturated fatty acids in distillates from soybean oil efficiently. [Method] In this experiment， by taking the residual rate and quality of ethyl palmitate as the main investigation indexes， using the method of ultra-high pressure & urea adduction joint with hypothermia， the detachment effects of three process factors named refrigerated temperature， refrigeration time and pressure were investigated， optimized by the orthogonal method. [Result] The results of ultra-high pressure & urea adduction joint with hypothermia showed that the optimum technological levels of the three parameters were as follows： 4 ℃， 90 min， 300 MPa. Under these conditions， the residual rate of ethyl palmitate was 21.87%， along with the quality declining from 137.31 g to 30.03 g. [Conclusion] After refrigeration， the ethyl palmitate could be separated efficaciously from the distillates of soybean oil， which made a favorable condition for further separation.

Key words Ultra-high pressure & urea adduction； Hypothermia； Distillates from soybean oil； Orthogonal test

脲包法是目前分离、提纯和富集脂肪酸族类化合物最常用的一种方法。其原理是在脂肪酸族和尿素的混合溶液中，尿素分子会选择性地结合碳原子数大于4个的直链碳原子，尿素分子通过它们之间强大的氢键力并以此直碳链为轴心，右手方向盘旋而上，形成一个正六棱柱。所以饱和脂肪酸及其衍生物多会被尿素分子包合形成稳定的结晶从溶液中析出，而多不饱和脂肪酸及其衍生物由于双键较多，碳链弯曲，具有一定的空间构型反而不易被尿素分子包合[1-3]。用此方法可以把脂肪族混合物中饱和脂肪酸及其衍生物分离出来，达到富集其中的多不饱和脂肪酸及其衍生物的目的。……