膜分离过程中儿茶素和咖啡碱含量变化研究

目的]探讨微滤膜、卷式超滤膜、卷式反渗透膜处理过程中儿茶素和咖啡碱含量变化情况。方法]采用0.2μm微滤膜和0.045μm、100 KD、13500D、5000D卷式超滤膜及100D卷式反渗透膜处理茶叶浸提液,HPLC分析膜滤过液和膜截留液中各儿茶素组分和咖啡碱含量,以及膜滤过液和膜截留液真空冷冻干燥样中各儿茶素组分和咖啡碱含量。结果]EGCG、EGC、ECG、GC、GCG、CG等儿茶素组分和咖啡碱主要集中在膜滤过液中,膜处理后分子量均小于500 D的EGCG、EGC、ECG、GC、GCG、CG等儿茶素组分和咖啡碱均有不同程度的损失。结论]膜对EGCG、EGC、ECG、GC、GCG、CG等儿茶素组分和咖啡碱的截留效果较差,推测膜处理后儿茶素和咖啡碱损失的主要原因为膜对儿茶素组分和咖啡碱可能具有一定的吸附作用,而这种吸附作用可能与所用的膜材质有关。

Study on the Content Change of Catechins and Caffeine in Membrane Separation Processing

Objective] The content change of tea catechins and caffeine in microfiltration membrane,roll membrane,rolling type reverse osmosis membrane separation processing was studied.Method] The tea extract solution was processed by 0.2 μm microfiltration membrane and 0.045 μm,100 D,13500D,5000D ultrafiltration membrane and 100 D reverse osmosis ultrafiltration membrane.The content of tea catechins component and caffeine in membrane filtration solution and membrane solution and their freeze dried sample was analyzed by HPLC.Result] EGCG,EGC,ECG,GC,GCG,CG and caffeine were mainly concentrated in the membrane filtration solution.The content of EGCG,EGC,ECG,GC,GCG,CG and caffeine,which molecular weight were less than 500D and lost in varying degrees.Conclusion] The membrane interception effect on the EGCG,EGC,ECG,GC,GCG,CG and caffeine was poor.The main reason of catechins and caffeine loss by membrane treatment was that the membrane might have certain adsorption on the catechin and caffeine.And the adsorption effect may be related to the membrane material.