柚子皮中果胶的提取工艺优化

Optimization of the extraction process of pectin from shaddock peel

目的优化酸提醇沉法提取柚子皮中果胶的工艺。方法以液料比、溶液p H值、提取温度、提取时间为实验因素,果胶提取率为评价指标,进行L_9(3~4)正交试验设计,3水平4因素响应面实验设计,最后对提取的果胶进行理化性质分析。结果 2种方法相比较,实验因素对评价指标的影响权重基本一致,即提取温度>溶液p H>液料比>提取时间,但最佳工艺和果胶提取率略有不同。正交试验确定的最佳工艺条件为液料比25:1(m L:g)、溶液p H 2.0、提取时间100 min、温度80℃;响应面实验确定的最佳工艺条件为:液料比26:1(m L:g),溶液p H1.9,提取时间106 min,提取温度77℃。连续6组实验取平均值为21.31%,响应面提取率比正交提高了6.6%。结论本实验建立的响应面模型可用于实际柚子皮酸提果胶过程预测,为柚子皮生产高值化利用和果胶的开发提供依据。

Objective To optimize the acid extraction and alcohol precipitation method for the extraction of pectin from shaddock peel.Methods Taking liquid-material ratio,p H value of solution,extraction temperature and extraction time as experimental factors,and taking pectin extraction rate as evaluation index,orthogonal experiment design of L_9（3～4） and response surface experiment design of 3 levels and 4 factors were carried out,and physical and chemical properties of extracted pectin were analyzed.Rusults Compared with the 2 methods,the weight of the test factors on the evaluation index was basically the same,the extraction temperature p H the ratio of liquid to material the extraction time,but the optimum process and the extraction rate of pectin were slightly different.The optimum process conditions of orthogonal experiment were as follows：liquid-to-solid ratio was 25：1（m L：g）,p H of solution was 2.0,extraction time was 100 min,extracting temperature was 80 ℃.The optimum process conditions of response surface experiment were as follows：liquid-to-solid ratio was 26：1（m L：g）,p H of Solution was 1.9,extraction time was 106 min,extracting temperature was 77 ℃.The mean value of repeated experiments was 21.31%,and the extraction rate by response surface method was 6.6% higher than orthogonal.Conclusion The response surface model established in this experiment can be used to predict the actual pectin extraction process of pomelo peel,which can provide a basis for the high-value utilization of pomelo peel and the development of pectin.