１实验目的 茶是我国的传统饮品。茶具有化痰消食、利尿解毒等功能，而这些功能都与茶中有效成分有关。 茶叶中化学成分的研究始于１８２７年人们在茶叶中发现嘌呤碱化合物。之后，随着科学技术的发展和进步，迄今已在茶叶中鉴定出４５０种以上的有机成分和１５种以上的无机元 1 The purpose of the experiment Tea is China’s traditional drinks. Tea has phlegm digestion, diuretic detoxification and other functions, and these functions are related to the active ingredients in tea. The chemical composition of tea began in 1827 people found in tea purine compounds. Since then, with the development and progress of science and technology, up to now, over 450 kinds of organic components and more than 15 kinds of inorganic elements have been identified in tea