Response surface methodology was used to optimize the microwave-assisted extraction of pectin from fresh citrus pomace. Pectin yield was investigated with respect to four process conditions including microwave power, solid-to-solvent ratio, microwave treatment time and pH. An analysis of variance showed that pectin yield was affected significantly by the linear termsX1 (pH),X2 (microwave treatment time) andX3 (microwave power) and the interactive termsX1X3 in the fitted regression model had sigificant effects on pectin yield, neither of the quadratic termsX1X2 andX2X3 had significant effects, while the quadratic termsX12 andX32 had highly signifinant effects. These demonstrate that the effects of the factors (process conditions) on pectin yield were not simply linear. In view of practical feasibility, efficiency and other comprehensive factors, the optimal conditions for the microwave-assisted extraction of pectin from fresh citrus pomace were determined as 626 W of microwave power, 5.6 min of microwave treatment time, solvent pH 1.5, and 1:30 (g/mL) of solid-to-solvent ratio. The predicted maximum pectin yield under the optimized conditions was 7.1%, whereas the average actual value of 7.05% (n = 3).%应用微波辅助提取柑橘鲜皮渣中的果胶,探讨微波功率、料液比、微波时间和pH值4因素对柑橘鲜皮渣中果胶得率的影响。并利用响应面法对微波辅助提取果胶的工艺条件进行优化。回归方差分析结果表明:模型中一次项X1(pH值)、X2(微波时间)、X3(微波功率)对果胶得率的影响均达到显著水平;交互项X1X3的影响显著,但X1X2、X2X3不显著;二次项X12、X32均表现为极显著。表明各因素对果胶得率的影响不是简单的线性关系。考虑到实验的可行性以及效率等综合因素,确定微波辅助提取柑橘鲜皮渣中果胶的最佳工艺条件为微波功率626W、微波时间5.6min、pH1.5、料液比1:30(g/mL),模型预测果胶得率为7.1%,在此微波条件下进行3次重复实验,果胶的平均得率为7.05%。
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