超临界CO_2萃取洋葱精油的试验研究

Experimental Study on the Extraction Process for Onion Essential Oil by Supercritical CO_2

采用单因素试验和正交试验相结合的方法研究超临界CO2萃取洋葱精油的工艺。得到的最佳工艺条件为萃取压力28 MPa、萃取温度45℃、萃取时间300min、一级分离压力7 MPa、温度40℃、二级分离压力5MPa、温度35℃、冻干红洋葱粉、粒径:0.38mm<D<0.83mm、CO2流量(10±2)L/h。在此条件下,洋葱精油的得率为0.5119%。通过正交试验确定了超临界CO2萃取洋葱精油得率的主要影响因素的顺序依次为压力(A)>时间(C)>温度(B)。

Abstract： The extraction process of onion essential oil from onion using supercritical COz is studied via orthogonal experiment and single-factor experiment. The results show that the optimum extraction conditions are as follows： the extraction pressure of 28 MPa, the extraction temperature of 45 ℃, the extraction time of 300 min, CO2 circulation flow rate of （10±2） L/h, the particle size of 0.38 mm〈D〈0. 83 mm, the primary separation pressure of 7 MPa, the primary separation temperature of 40 ℃, the secondary separation pressure of 5 MPa, the secondary separation temperature of 35 ℃. Under these conditions, the yield of onion essential oil would reach 0. 5119%. It is found that the order of the influences factors on the yield of onion essential oil is pressure〉time〉temperature.