以一芽一叶茶鲜叶为原料,进行连续摊放（水分78%~61%）处理,取不同含水率摊放叶,分别进行液氮速冻和冷冻干燥,测定茶多酚、儿茶素各组分、氨基酸及各游离组分、咖啡碱、叶绿素、维生素C及可溶性总糖等含量,研究茶鲜叶摊放过程中主要生化成分的动态变化。结果表明,随着摊放时间的增加,茶鲜叶中含水率下降逐渐加快,干物质质量下降;茶多酚和儿茶素总量呈现前期下降后期有所上升的趋势,酯型儿茶素总量逐渐下降,鲜叶和摊放叶中检测不到没食子酸儿茶素(GC);氨基酸总量呈上升趋势,不同游离组分呈现不同的变化趋势;咖啡碱和可溶性总糖含量呈逐渐上升趋势,叶绿素和维生素C含量呈逐渐下降趋势。摊放过程中茶鲜叶不同生化成分具有不同的动态变化规律,本研究为提高名优绿茶品质提供一定的理论基础。
By using of a leaf and a bud shoot as fresh tea leaves material, and spread continuously (78%~61%), spread leaves with different moisture content were fixed with liquid nitrogen and freeze-dried. then the contents of tea polyphenols and catechin components, total amino acids and free components, caffeine, total chlorophyll, Vc and total soluble sugar were determined to study the dynamic change of biochemical components of fresh tea leaves during spreading. Results showed that with increasing of spreading time, moisture content of fresh tea leaves decreased rapidly gradually, weight of dry substance decreased; contents of tea polyphenols and total catechins decreased at first and then increased during spreading, total esters-catechins decreased gradually, but GC could not be detected in fresh tea leaves and spread tea leaves, content of total amino acids increased, but different free amino acid have different changing trends during spreading; content of caffeine and total soluble sugar increased while total chlorophyll and Vc decreased gradually. Different biochemical components of fresh tea leaves changes in different rules during spreading. This study provides supplied some theory for improving the quality of premium green tea.
[1] 张堂恒. 张堂恒选集[M]. 杭州: 浙江农业大学出版社, 1989.
[2] 程启坤. 茶化浅析[M]. 杭州: 浙江农业大学出版社, 1982: 172~177.
[3] 刘勤晋. 绿茶. 见: 安徽农学院主编. 制茶学. 北京: 中国农业出版社, 1979: 86~91.
[4] 郑继辉. 鲜叶摊放过程中失水规律研究[J]. 福建茶叶, 1988, (4): 30~32.
[5] Johnson AL.Manufacture-Section 14, Tea Planters Handbook[M]. Tea Research Foundation (Central Africa), PO Box 51, Mulanje, Malawi, 1990.
[6] Hampton MG.Production of black tea. In: KC Willson, MN Clifford, ed. Tea-Cultivation to Consumption. London: Chapman and Hall, 1992: 459~511.
[7] Robertson A.The chemistry and biochemistry of black tea production-the non-volatiles. In: KC Willson, MN Clifford, ed. Tea-Cultivation to Consumption. London: Chapman and Hall, 1992: 555~597.
[8] Dev Choudhury MN, Bajaj KL.Incorporation of 14C-compounds into amino acids and polyphenols of excised tea shoots[J]. Plant Biochem J, 1979, 6: 16~23.
[9] Tomlins KI, Mashingaidze A.Influence of withering, including leaf handling, on the manufacturing and quality of black teas-a review[J]. Food Chemistry, 1997, 60(4): 573~580.
[10] 陈宗道, 周才琼, 童华荣. 茶叶化学工程学[M]. 重庆: 西南师范大学出版社, 1999: 3~19.
[11] 林娇芬, 林河通, 陈绍军, 等. 自然摊放萎凋工艺对柿叶茶品质改进的影响[J]. 福建农林大学学报(自然科学版), 2007, 1: 102~105.
[12] 王云, 李春华. 名优茶氨基酸含量变化规律及其影响因素研究[J]. 西南农业学报, 2006, 19(6): 1121~1126.
[13] Roberts EAH.Calculation of moisture content of withered leaf from percentage wither[M]. Assam, India: Tocklai Experimental Station, 1948.
[14] Ullah MR, Roy PC.Effect of withering on the polyphenol oxidase level in the leaf[J]. J Sci Food Agric, 1982, 33: 492~495.
[15] Bhatia IS.Chemical aspects of withering[J]. Two and a Bud, 1962, 9: 26~30.
[16] Roberts GR, Sanderson GW.Change undergone by the free amino acids during manufacture of black tea[J]. J Sci Food Agric, 1966, 17: 182~188.
[17] Dev Choudhury MN, Bajaj KL.Role of chlorophylls, amino acids and sugars in tea[J]. Two and a Bud, 1980b, 27: 16~20.
[18] Bhuyan LP, Mahanta PK.Studies on fatty acid composition in tea Camellia sinensis[J]. J Sci Food Agric, 1989, 46: 325~330.
[19] Dev Choudhury MN, Bajaj KL.Biochemical changes during withering of tea shoots[J]. Two and a Bud, 1980a, 27: 13~16.
[20] 张丽霞, 施兆鹏. 红茶和绿茶初制过程中维生素C变化动态研究[J]. 湖南农学学报. 1991, 17: 627~632.
浙公网安备 33019902000101号 
