摇青工艺对山东红茶品质的影响及其机理研究

Effect and Mechanism of Shaking Green Technology on the Quality of Shandong Black Tea

为探究摇青处理对红茶品质的影响,以‘黄山群体种’和‘金萱’秋季(9月)一芽二叶鲜叶为原料,以传统工艺加工红茶为对照,设三个摇青工艺处理试验,观测鲜叶样品的外观特征与细胞破损率变化,测定相关香气代谢途径的酶基因表达水平,以及对红茶样进行感官品质评价及主要品质成分测定分析。与对照鲜叶样相比,摇青处理鲜叶的LOX1、LOX4、GGPS、GPS酶基因表达水平均有不同程度提升;与对照红茶样相比,摇青处理可有效提升具有花香特征的己烯醛类和己烯醇类香气物质的比例,游离氨基酸、可溶性糖、茶黄素和茶红素总量显著升高(p<0.05)。结果表明摇青处理可使红茶中花香成分增加,滋味更醇厚;以叶片细胞破损率为12%~17%(‘黄山群体种’摇青2次,‘金萱’摇青3次)处理效果最佳。

In order to explore the effect of shaking treatment on the quality of black tea,the fresh leaves of the Camellia sinensis cv.‘Huangshan Population’and‘Jinxuan’in autumn(September)with one bud and two leaves as raw materials,and the traditional techniques for processing black tea as a control,three shaking treatment experiments were set up to observe the appearance characteristics and changes in cell damage rate of fresh leaf samples,determine the expression levels of enzyme genes related to aroma metabolism pathways,and carry out sensory quality evaluation and determination and analysis of main quality components of black tea samples.Compared with the control fresh leaf samples,the expression levels of LOX1,LOX4,GGPS,GPS enzyme genes in fresh leaves with shaking treatment were all increased to varying degrees;Compared with the control black tea,shaking treatment can effectively increase the proportion of hexenol and hexenol aroma compounds with floral characteristics,and the total amount of free amino acids,soluble sugars,theaflavins,and thearubigins is significantly increased(P<0.05).The results showed that shaking treatment can increase the floral components in black tea,and make the taste more mellow.The best treatment effect was when the damage rate of leaf cells reaches 12%~17%(the Camellia sinensis cv.‘Huangshan population’was shaken twice,‘Jinxuan’tea cultivar was shaken three times).