精炼工艺对杜仲籽油品质的影响

Influence of refining process on qualities of Eucommia ulmoides seed oil

为了实现杜仲籽油的开发利用,研究了精炼过程对杜仲籽油理化指标、脂肪酸组成、VE含量以及氧化稳定性的影响。结果表明:随着精炼过程的进行,杜仲籽油的折光指数、酸值、过氧化值、VE含量、磷脂含量以及氧化稳定性均呈降低趋势,碘值、皂化值变化不显著;精炼后,酸值(KOH)由6.33 mg/g降低到0.24 mg/g,过氧化值由9.12 mmol/kg降低到2.51 mmol/kg,达到了GB2716—2005《食用植物油卫生标准》的要求;杜仲籽油中的脂肪酸主要为亚麻酸、油酸、亚油酸和棕榈酸,精炼过程对杜仲籽油脂肪酸组成的影响不显著;脱臭油中VE含量为1 191.77 mg/kg,与杜仲籽毛油(VE含量2 353.98 mg/kg)相比减少了49.37%;精炼过程对杜仲籽油的氧化稳定性具有显著的影响,氧化诱导时间由毛油的5.03 h缩短到脱臭油的0.17 h。

In order to realize the development and utilization of Eucommia ulmoides seed oil,the influences of refining process on the physicochemical indexes, fatty acid composition, VE content and oxidative stability of Eucommia ulmoides seed oil were analyzed. The results showed that the refractive index, acid value, peroxide value, VE content, phosphorus content and oxidative stability presented descendent tendency along with the refining. However, iodine value and saponification value didn’t change significantly. After refining, the acid value reduced from 6.33 mgKOH/g to 0.24 mgKOH/g, and peroxide value reduced from 9.12 mmol/kg to 2.51 mmol/kg, which met Hygienic Standard for Edible Vegetable Oil GB 2716—2005.The main fatty acids in Eucommia ulmoides seed oil were linolenic acid, oleic acid, linoleic acid and palmitic acid, and there was no significant change in fatty acid composition in the refining process. The VE content reduced from 2 353.98 mg/kg of crude oil to 1 191.77 mg/kg of deodorized oil, which decreased by 49.37%. Meanwhile, refining had a significant influence on the oxidative stability of Eucommia ulmoides seed oil, and the oxidation induction time reduced from 5.03 h of crude oil to 0.17 h of deodorized oil.