醇法脱酸条件对小米糠油品质和得率影响的研究

Effects of Alcohol Deacidification Refining Conditions of Millet Bran Oil's Quality and Yield

研究高酸价小米糠毛油醇法脱酸的最佳工艺条件,并对不同氧气体积分数下脱酸小米糠油的酸价、过氧化值、VE和油保存率进行比较分析。结果表明,乙醇脱酸最适次数为2次;常压环境下醇法脱酸最佳工艺条件为料液比1∶2.3,乙醇体积分数80%,脱酸温度35℃;按此条件脱酸2次,所得油的酸价为2.637 mg KOH/g,VE保存率为51.02%。在减压低氧条件下脱酸对脱酸油品质的影响为氧气体积分数低于8.5%时,随着氧气体积分数的增大酸价明显升高,但VE保存率变化不大;氧气体积分数大于8.5%时酸价升高缓慢,但VE保存率迅速降低;过氧化值随着氧气体积分数的增大而增大;而氧气体积分数对醇法脱酸油保存率影响不大。

The optimal conditions of alcohol deacidification in refining high-acid millet bran oil is studied,and the refining under different oxygen concentrations of millet bran oil in acid value,peroxide value,VE and oil retention rate is compared and analyzed. The results show that the optimal number of ethanol deacidification is twice. The optimal conditions of alcohol deacidification at atmospheric pressure is liquid-solid ratio 1∶2.3,ethanol concentrations 80%,refining temperature 35 ℃.Refined twice at the optimal conditions the acid value of oil is 2.637 mg KOH/g,VE saving rate is 51.02%. The influences of refined oil＇s quality under the optimal conditions at low oxygen concentrations is：when oxygen concentration is lower than8.5%,with the increasing of oxygen concentration acid value increased significantly but the survival rate of VE had little change;When oxygen concentration is higher than 8.5%,acid value increased slowly but VE survival rate falled rapidly.The peroxide value increased with the increasing of oxygen concentration,but the oxygen concentration has little influence on oil saving rate.