本文通过对茶叶进行微波预处理和空白对照作对比,探讨了在微波预处理条件下超临界CO₂(SC-CO₂)技术对茶叶中咖啡因和表没食子儿茶素没食子酸酯（EGCG）的影响,并通过正交实验确定了超临界CO₂技术脱除茶叶中咖啡因的最佳工艺参数。结果表明,利用微波预处理的方法能明显提高茶叶中咖啡因的脱除率,而对EGCG损失的影响则较小;正交实验中,影响咖啡因脱除率主要因素的依次顺序为萃取压力>萃取温度>夹带剂用量>茶叶含水量。

The influences of microwave pretreatment on the extraction rate of caffeine and EGCG from green tea with supercritical CO₂(SC-CO₂) extraction technology were analyzed. And through orthogonal experiments, the best parameter of decaffeination from tea with SC-CO₂ extraction technology was ascertained. The result showed that the decaffeination rate from the tea under microwave pretreatment could improve obviously, but the influences on EGCG was small, by using the orthogonal design test , the order of the influences factors on decaffeination rate of the caffeine is extracting pressure>Extracting temperature> entrainer>water content of the tea.