膜技术在茶叶深加工中的应用研究

Application of Membrane Technology to Comprehensive Processing of Tea

选用0.1μm微滤膜对茶水提离心上清液进行微滤处理,探讨了微滤温度对干物率、咖啡碱、各儿茶素组分以及微滤处理对产品冷溶性的影响.同时,选用不同的超滤膜对儿茶素粗提液进行超滤处理,比较分析了超滤处理对儿茶素各组分比值和儿茶素终端产品色素的影响.结果表明,微滤滤出液的干物率、咖啡碱及各儿茶素组分含量随微滤温度的升高而增加,产品的各项冷溶性指标明显好于对照样产品;选用超滤膜 1可获得酯型儿茶素/非酯型儿茶素比值较小的产品,选用超滤膜 2可获得比值较大的产品;超滤膜 1比超滤膜 2能更有效地去除儿茶素终端产品色素.

The microfiltration test of tea liquor is carried out by using 0.1 μm microfiltration membrane. Besides the effects of microfiltration temperature on the rate of dried substance, caffeine, catechin and the cold solubility of products are discussed. At the same time, the ultrafiltration tests on semifinished catechin liquor are also carried out by using ultrafiltration membrane, with an analysis of the effects of ultrafiltration on the rate of catechin and the pigments of finished products.Results show that the rate of dried substance, caffeine and catechin in the microfiltrated liquor increase with the increase of operating temperature, and the products possess better cold solubility .The products with a minor or big ratio of estered catechins could be acquired by using ultrafiltration membrane 1 or 2 respectively ; furthermore,it is more effeetive to get rid of pigments of finished catechin products with ultrafiltration membrane than with ultrafiltration membrane 2.