响应面优化亚临界萃取菜籽低温压榨饼中油脂的工艺及其品质评价

采用Box-Behnken响应面设计优化亚临界萃取菜籽低温压榨饼中油脂的工艺，并将所得油的品质与正已烷、超临界CO2萃取油进行比较。结果表明：液料比和萃取时间对油脂提取率的影响极显著(p<0.01)；液料比与萃取时间存在显著的交互作用（p<0.05）；经优化后，在35℃下，设定液料比为8.3 mL/g，萃取90 min，菜籽油的提取率最高达95.10%。通过亚临界萃取得到的菜籽油磷含量为113.20mg/kg，约为正已烷萃取菜籽油(磷含量232.48mg/kg)的一半，油脂酸价与过氧化值都较正已烷萃取菜籽油低；亚临界萃取的菜籽油除磷含量与超临界萃取菜籽油差异显著外，其它品质指标，如酸价、过氧化值、甾醇及生育酚含量均与超临界萃取油差异不明显。

Optimization of Subcritical Fluid Extraction from Rapeseed Cold Press Cake by Response Surface Methodology and Oil Quality Evaluation

The response surface methodology of Box-Behnken is used to optimize oil extraction processing by subcritical fluid from rapeseed cold press cake. The quality of the oil and meal obtained is studied and compared with n-hexane extraction and supercritical CO2 extraction. The experiment result indicated that the effect of solvent ratio to material and extraction time on oil yield were more significant than extraction temperature. The interaction between extraction time and solvent ratio to material had a significant effect on oil yield. The optimum operation parameters of subcritical butane extraction were: solvent ratio to material 8.3mL/g, extraction time 90min and extraction temperature 35℃．Under this optimal condition, the oil yield was 95.10%. The subcritical butane extraction of rapeseed oil from cold press cake has a half of phosphorus contents, which was 113.20mg/kg, better acid and peroxide value compared to n-hexane extraction. The phosphorus content of rapeseed oil extracted by subcritical butane was significantly different from that of supercritical extraction oil, but the other quality indexes，such as acid value, peroxide value, sterol and tocopherol contents, were slightly different from that of supercritical extraction oil.