分别选用铁观音、黄棪、金观音和黄观音春茶新梢为供试材料,对其新梢不同生育阶段及清香型乌龙茶制作过程中的水浸出物、茶多酚、游离氨基酸、可溶性糖等与茶叶滋味品质密切相关的主要生化成分进行检测分析.结果表明,低“酚氨比”和高咖啡碱为茶树品种幼嫩新梢的主要特征；当其萌长至中、小开面2～4叶时,除可溶性糖有明显增加外,其他生化成分均呈下降趋势.在茶树新梢生育过程中各主要(或主体)生化成分的动态变化较清香型乌龙茶制作工艺的影响更为明显.各品种茶样滋味品质相关成分测定结果经数据标准化预处理后,再行相似度分析(夹角余弦)、聚类分析(欧氏距离-近邻法)和主成分分析均可获得较为一致的可视化模式识别结果.在茶树新梢生育过程中,各茶样主要生化成分的化学模式存在较大差异,而清香型乌龙茶在制品则可按品种相互区分.%The spring shoots harvested from the buds of Tieguanyin, Huangdan, Jinguanyin and Huangguanyin (Camellia sinensis) were used as materials for the experiments, and the contents of predominant biochemical components related to tea taste quality were determined in samples prepared during the period of shoot growth and the process of fresh scent-flavor Oolong tea, which were water extracts, total polyphenols, free amino acids, water soluble sugars, etc. The results showed that the low ratio of tea polyphenols to free amino acids and high caffeine content were the primary characters of tender shoots. As grew into two to four leaves with a banjhi bud, all of the biochemical components contents declined rapidly except for the increase of water soluble sugars. These biochemical components changed more obviously during the period of shoot growth than those in the process of fresh scent-flavor Oolong tea. When given data standardization to the contents of biochemical compositions in each tea samples, the consistent visualized pattern recognition results would be obtained by either cosine similarity analysis, or nearest neighbor clusters analysis based on Euclidean distance or principal component analysis. The biochemical patterns of spring shoots varied much differently, but their WIP (Work in process) of fresh scent-flavor Oolong tea could be well classified according to tea cultivars.
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