3种萎凋环境对白茶含水量与生化成分含量的影响

Effects of 3 kinds of withering environments on water content and biochemical components content of white tea

中文关键词:  白茶  萎凋环境  含水量  茶多酚  游离氨基酸

英文关键词:white tea  withering environment  water content  tea polyphenols  free amino acids

中文摘要:

      目的 探究3种萎凋环境对白茶含水量与生化成分含量的影响。方法 以福鼎大白茶一芽二叶新稍为原料, 采用传统室内自然萎凋、抽湿萎凋和空调萎凋3种萎凋方式, 测定萎凋过程中茶叶含水量、茶多酚、游离氨基酸和黄酮类化合物含量。结果 3种萎凋方式的茶叶含水量在萎凋24~32 h期间均迅速降低, 尤其是抽湿萎凋, 从44.11%降至16.03%; 整体上茶多酚含量都是先升高后降低, 整体变化范围小; 与鲜叶对比, 室内自然萎凋和抽湿萎凋中茶叶的黄酮类含量均显著增加, 三者的游离氨基酸含量皆有显著增加, 增幅为78.97%~110.3%; 萎凋结束时, 室内自然萎凋和抽湿萎凋的黄酮类与游离氨基酸含量皆显著高于空调萎凋。结论 抽湿萎凋的茶叶在32 h时水分含量基本达到萎凋叶标准, 且氨基酸和黄酮类含量均在较高水平, 说明抽湿萎凋具有成为效率与制优率兼备的潜能, 本研究为提高白茶萎凋工效和毛茶制优率提供理论参考。

英文摘要:

      Objective To explore the effects of three withering environments on water content and biochemical components of white tea. Methods The shoots composed of one bud and two leaves were collected from Camellia sinensis cv. Fuding dabaicha, then subjected to the treatments of indoor natural withering, dehumidifying withering and air conditioning withering, respectively. The content of water, tea polyphenols, free amino acids, and flavonoids in the different wilting leaves were measured and analyzed. Results The water content in the 3 kinds of different treated tea leaves were decreased rapidly during the withering period (24–32 h after the initial of withering), especially from 44.11% to 16.03% in dehumidifying withering; additionally, the tea polyphenol content were increased at first and then decreased with a small variation range. Compared with fresh leaves, the content of flavonoids in indoor natural withering and dehumidifying withering were significantly accumulated, the content of free amino acids in all the three treatments were significantly increased, with the increment being 78.97%–110.3%. At the end of withering, the content of flavonoids and free amino acids in indoor natural withering and dehumidifying withering treatments were significantly higher than those in air conditioning withering. Conclusion After withered 32 h, the moisture content of tea reach the standard of withering leaves, and the content of amino acids and flavonoids are at a high level, dehumidifying withering can be a promising approach with the acceptable efficient and premium quality. The research provides a theoretical reference for improving the efficiency of withering and the quality of raw tea in white tea.