内部沸腾法提取茶多酚工艺优化及其与水提法的比较

采用内部沸腾法提取茶多酚,研究解吸剂(乙醇)浓度、解吸时间、解吸剂料液比、提取剂(热水)料液比、提取时间、提取温度等六个因素对茶多酚得率的影响,在单因素实验基础上,设计正交实验,优化茶多酚提取条件。与水提法进行比较,考察两种工艺对儿茶素组分以及抗氧化活性的影响。结果表明,内部沸腾法提取茶多酚的最佳工艺参数为:以50%的乙醇为解吸剂、室温解吸10 min、解吸剂料液比1:6 g/mL;再以水为提取剂、提取剂料液比1:110 g/mL、100℃提取10 min,在此最优工艺条件下茶多酚得率为22.45%±0.11%。与水提法相比,内部沸腾法将茶多酚得率提高了11.53%,高温提取时间缩短近80%,减少了高温对茶多酚活性的破坏,保留了更多的表儿茶素,茶多酚抗氧化活性显著(P<0.05)增强,是一种经济、快速、有效的提取方法,具有较好的工业化生产前景。

Optimization of Extraction Process of Tea Polyphenols by Internal Boiling Method and Comparison with Water Extraction Method

The extraction of tea polyphenols by inner ebullition was applied.To study the effect on extraction yield of tea polyphenols,the six factors of concentration of desorption agent(ethyl alaohol),the time of desorption,solid-liquid ratio of desorbent,the dosage of the extract(hot water),extraction time and extraction temperature were assayed.Based on single factor experiment,orthogonal test was designed to optimize extraction conditions of tea polyphenols. Compared with water extraction method,the effects of two processes on catechin components and antioxidant activities were investigated. A maximum extraction yield of tea polyphenols of 22.45%±0.11% was obtained under the optimized conditions:Concentration of desorption agent 50% ethanol solution;the time of desorption at room temperature 10 min;solid-liquid ratio of desorbent 1:6 g/mL;the dosage of the extract 1:110 g/mL;extraction time 10 min;the extraction temperature 100℃.Compared with water bath extraction,the extraction yield of tea polyphenols was increased by 11.53%,the high temperature extraction time was reduced by nearly 80%,the destruction of high temperature on the activity of tea polyphenols was avoided,more epicatechins were remained and antioxidant activities of tea polyphenols were strengthened significantly(P<0.05). Inner ebullition is an economical,rapid and effective method,which shows a very promising prospect for industrial applications in the extraction of tea polyphenols.