脱酸工艺对米糠油中功能因子含量影响的研究

Effect of deacidification process on the contents of functional factors in rice bran oil

以脱胶米糠油为原料,研究了醇萃取脱酸以及醇萃取脱酸后再经过碱炼或自制吸附剂吸附脱酸对米糠油中功能因子含量的影响。结果表明:甲醇和95%乙醇萃取脱酸均能较好地脱除游离脂肪酸(FFA),但从功能因子损失和米糠油得率来看,甲醇萃取脱酸效果明显好于95%乙醇,甲醇4次萃取脱酸后米糠油得率为63.95%,FFA脱除率为92.57%,谷维素、维生素E、植物甾醇的损失率分别为8.56%、32.86%、20.28%;对甲醇4次萃取脱酸后的米糠油采用质量分数为8.07%的碱液(Na OH溶液)进行碱炼脱酸时,其酸值(KOH)可降至1 mg/g以内,功能因子损失相对较少;自制吸附剂对甲醇4次萃取脱酸后的米糠油吸附脱酸可降低酸值,并且功能因子基本无损失。

Using degummed rice bran oil （ RBO） as raw material, the effects of alcohol extraction deacid-ification（ AED） , alkaline refining or adsorption deacidification by self-made adsorbent after AED on the contents of functional factors in rice bran oil were investigated. The results showed that both methanol and 95% ethanol extraction deacidification could remove free fatty acids （ FFA） easily. However, from the point of the loss of functional factors and the extraction rate of rice bran oil, methanol prevailed over 95%ethanol significantly. After methanol extraction deacidification for four times, the extraction rate of rice bran oil, removal rate of FFA and the loss rates of oryzanol, vitamin E and phytosterols were 63. 95%, 92. 57%, 8. 56%, 32. 86% and 20. 28%, respectively. The acid value could be reduced within 1 mgKOH/g when 8. 07% alkaline solution was adopted in the alkaline refining after RBO methanol extrac-tion deacidification for four times, meanwhile, the functional factors could be kept well. Additionally, the self -made adsorbent could reduce the acid value of deacidified RBO by methonal extraction for four times, and there was almost no loss of functional factors.