炒青绿茶儿茶素超临界CO2萃取工艺优化研究

摘要

The extraction conditions of catechin from roasted green tea by supercritical-CO 2 fluid extraction (SFE-CO2)were studied. Influences of extraction temperature, extraction pressure, materiel-liquid ratio, and extraction time on the content of catechin were investigated, and the effect of extraction conditions on the extraction rate of catechin from extracts was evaluated by single factor and orthogonal tests.Experimental results showed that the successive order of diferent effect factors on yield of catechin was extraction pressure>materiel-liquid ratio>extraction time>materiel granularity. The optimal extraction conditions of catechin from roasted green tea as follows:extraction temperature 50℃, extraction time 120 min, extraction pressure 25 MPa, 1∶2.5 of solid to liquid ratio was used as a modifier, and 0.65 mm of particle size. The maximum SFE-CO2 extracting rate of catechin 6.053 6%.%采用单因素试验和正交试验对炒青绿茶儿茶素超临界CO2萃取工艺进行探讨，确定萃取效果影响的程度从高到低依次为：萃取压力>夹带剂乙醇用量>萃取时间>萃取粒度，最佳萃取工艺为：底物与夹带剂（乙醇）之比为100 g/250 mL，萃取压力25 MPa，萃取温度50℃，粒度为60目，萃取120 min。按照该工艺茶叶中儿茶素粗提物的得率为6.0536%。