棉籽油与棕榈硬脂化学酯交换法制备零反式脂肪酸起酥油的研究

Chemical transesterification of cottonseed oil and palm stearin for preparation of zero trans fatty acids shortening

通过研究甲醇钠催化棕榈硬脂和棉籽油酯交换反应,以酯交换产物在20℃条件下固体脂肪含量(SFC)为指标,考察了反应温度、催化剂用量、反应时间对酯交换反应的影响。确定的最佳酯交换条件为:反应温度90℃,催化剂用量0.5%,反应时间60 min。通过酯交换产物SFC与市售焙烤型起酥油全统酥油SFC比较以及晶型分析,得出棕榈硬脂与棉籽油质量比为1∶1的酯交换产物,其SFC与市售焙烤起酥油全统酥油相似,结晶形态为β'型,且不含反式脂肪酸,符合零反式脂肪酸起酥油性质要求,适宜用作焙烤起酥油。

The transesterification of palm stearin and cottonseed oil catalyzed by sodium methylate was studied. The effects of reaction temperature, catalyst dosage and reaction time on the solid fat content （ SFC） at 20℃ of the transesterification product were investigated. The optimal transesterification condi-tions were determined as follows：reaction temperature 90℃,catalyst dosage 0. 5%,reaction time 60 min. Moreover,the SFC of the transesterification product was compared with commercial baking shortening Quantong butter and its crystal form was analyzed. The result showed that the transesterification product prepared by palm stearin and cottonseed oil with mass ratio 1∶1 had similar SFC with the commercial bak-ing shortening Quantong butter, zero trans fatty acids and β′ crystal form, which was suitable for being used as baking shortening.