茶叶茶多酚、咖啡碱提取及超滤-吸附综合分离纯化过程研究

介绍了采用三级错流提取茶叶有效成分茶多酚、咖啡碱的优化提取工艺。该工艺提取率高达９０％ 以上，其提取液经醋酸纤维素复合钛微孔体超滤膜初步纯化，可得到茶多酚含量大于４０％ 的部标三级品。并建立了茶叶水提取液超滤过程修正凝胶极化模型。超滤透过液经聚酰胺树脂吸附、８５％ 乙醇洗脱，得到茶多酚含量大于９０％ ，咖啡碱含量低于４％ 的部标茶多酚一级品。该工艺具有不另外添加物质、不使用有毒溶剂、工艺简单等特点。

Study on the extraction,separation and purification of tea polyphenols and caffeine by ultrafiltration and adsorption

An experimental investigation is made in the paper on the optimal conditions of extracting tea polyphenols(TP)and caffeine.By means of 3 step cross current extraction,the yleld of TP and caffelne can come up to more than 90%.The pretreatment of tea extract by CA Ti composite ultrafiltration membrane(CATUM)can result in a crude product with a TP content of more that 40%.A modified gelification model for the ultrafiltration process is also set up in the paper.After the permeated solution from CATUM is adsorbed by polyamide resin and eluted by 85% alcohol liquor,a purified product with a TP content of more than 90% and a caffeine content of less than 4% can be obtained.Compared with traditional processes,the new technology has the advantages of simplicity in operation and no need to add other substances or use toxic solvents.