以猕猴桃籽为试验原料,在单因素试验的基础上,采用响应曲面分析法建立了超临界CO2萃取猕猴桃籽油萃取率的二次多元回归方程,探讨了压力、温度、CO2流量等关键因素对萃取率的作用规律。结果表明,萃取压力、温度、CO2流量对萃取率影响显著,萃取压力和温度交互效应影响显著。根据萃取率回归方程对猕猴桃籽油的超临界萃取工艺参数进行了优选,最优工艺参数为:压力31.7MPa,温度40.2℃,CO2流量27.4kg/h,该条件下萃取率高达32.57%,与试验值31.24%仅有4.5%的误差,证实了该方程的预测值与试验值之间具有较好的拟合度。超临界CO2萃取的猕猴桃籽油与己烷提取的油脂在脂肪酸组成上没有显著差别。
Response surface methodology (RSM) was used for establishing the model of a second order quadratic equation for the extraction rate of Kiwi-fruit seed oil by supercritical CO2 extraction with Kiwi-fruit seed as raw material. The effects of the key factors such as extraction pressure, temperature and CO2 flow rate on the extraction were investigated based on the results of the single-factor design. The results show that the interactions between extraction pressure and temperature, and the pressure, temperature and CO2 flow rate have a significant effect on the extraction rate. The optimal parameters for the supercritical CO2 extraction determined by the regressive equation are pressure of 31.7 MPa, temperature of 40.2℃, CO2 flow rate of 27.4 kg/h and the extraction rate of Kiwi-fruit seed oil of 32.57%. The regressive equation predicted the extraction rate with an error of 4.5%. The error shows that the regressive equation fits the extraction process perfectly. The fatty acid of Kiwi-fruit seed oil extracted with supercritical CO2 extraction and hexane extraction are similar.