| In order to explore the effects of shape-making technique on the quality and chemical components of Oolong tea, and clarify the suitable shapes for different Oolong tea cultivars, in this experiment, primarily or half mature fresh buds, with two to four springtime leaves, of five famous cultivars for Oolong tea in Fujian province, which were Tieguanying, Huangdan, Benshan, Shuixian, Rougui, were processed into Oolong tea with six different appearances, which were string-like, curling, half ball-like, brick-like, straight string-like, flat, adopting different shape-making techniques. The results of sensory evaluation and analyses of the determination of chemical components in these various shape-making tea processed with different cultivars showed as follows.First, comparing the differences of sensory quality of six shape-making Oolong tea of each cultivars, it was known that brick-like shape was better than string-like shape and half-ball like shape, the same between curling shape and half-bail like shape, and that flat shape should be washed out. But there were no prominent differences between other shapes. Furthermore, shapemaking technique had greater effects on the quality of Benshan and Rougui than that of other cultivars. Curling shape was the best for Benshan, but straight string-like shape for Rougui.Second, the main savory and tinctorial components were determined in each shape-making tea processed with five cultivars. The results indicated that curling shape -making technique could get higher. soluble substances for Oolong tea, soluble sugar was higher in half-ball like tea, brick-like tea, and curling tea, and brick-like tea possessed the highest caffeine than that of other shapes among each cultivars. Moreover, tea heated rolling, was favorable for the preservation of chlorophylls, and tea kneaded with a bag contributed to the decompounding and transforming of polyphenols than that of tea not kneaded with a bag. As cultivars were concerned, shape-making technique showed greater effects on the savory and tinctorial components of Rougui and Shuixian than that of fleguanying.Third, analyses of the results of determination of aromatic components indicated that shape-making technique had different effects on 64 varieties of determined aromatic components of Tiegucanying and shutxian, and indole, Benzoic Acid, Hexyl Ester, Benzeneacetic Acid, ethyl Ester, 1,3 ,5,8-Undecatetraene, (Z,Z)-9, I 2-Octadecadienoic Acid, Methyl Ester, Linalool Oxide(IV), were the most evident. Besides, the effects of shape-making technique on each shape-making tea were directly pertinent to the varietiesof not determined aromatic components.According to their diversities of total contents of extractive oil in different shape-making tea of two cultivars, curling shape-making technique was not the best for fleguanying in aromatic quality, but half ball-like shape, fried and rolled, was good for improving the contents of extractive oil. As to Shuixian culitvar, string shape-making technique didn's show its superiority in contents of extractive oil too. However, brick shape-making technique is good for accumulation of aromatic contents.Different shape-making techniques showed no evident effects on the indexes of terpene alkene of Tieguanying and Shuixian. In addition, Nerolidol, (Z)-Hexanoic Acid, 3-Hexenyl Ester+Benzeneacetaldehyde, 1 -Penten-3-ol, Hexanal, Linalool, Geraniol were common main aromatic compoents in each shape-making tea, made with Tieguanying cultivar, and the same to Shufxian cultivar were Nerolidol, Geraniol, (Z)-Hexanoic Acid, 3-Hexenyl Ester+Benzeneacetaldehyde, Hexanoic Acid in this experiment. Because these components didn's change greatly according to shape-making technique, they would be respectively considered as aromatic components determined by characteristics of material from Tieguanying and Shuzxian cultivars, differences of zuoqing technique, etc.If considering aromatic characteristics of tea with different appearances as the same type, according to whether the ratio of simila...
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