响应面法优化米糠超临界流体脱脂工艺

运用响应面法优化米糠超临界流体脱脂纯化工艺。在单因素试验基础上，以萃取温度、萃取时间、萃取压力为响应因素，脂类及异杂物质脱除率为响应值，根据中心组合Box-Benhnken 试验设计原理采用三因素三水平的响应面分析法，确定最佳脱脂工艺。结果表明当萃取温度46℃、萃取时间94min、萃取压力27MPa 时脂类及异杂物脱除率18.34%(g/100g 米糠)，脱脂除杂有效率为92.19%，与理论值较为接近，表明数学模型对优化脱脂工艺可行。方差分析结果表明各因素对米糠脱脂除杂率的影响强弱顺序依次为萃取压力＞萃取温度＞萃取时间。

Optimization of the Supercritical Fluid Degreasing of Rice Bran by Response Surface Methodology

Supercritical carbon dioxide extraction was applied to degrease rice bran in the present study. The process conditions for the degreasing of rice bran was optimized by response surface methodology. The effects of extraction temperature, extraction time and extraction pressure on lipid removal rate were explored with Box-Benhnken experimental design coupled with response surface analysis on the basis of single factor experiments. The optimal extraction parameters were determined as follows: extraction temperature, 46 ℃; extraction time, 94 min; and extraction pressure, 27 MPa. A lipid removal rate of 18.34% (g/100g rice bran, or 92.19% degreasing efficiency) under these optimal extraction conditions, which was close to the theoretical value. Therefore, the developed mathematical model was reliable in predicting lipid removal rate. The analysis of variance exhibited that the importance of the above three factors affecting lipid removal rate from strong to the weak were extraction pressure, extraction temperature and extraction time.