摘要
早春茶树遭受冻害后会造成当年春茶减产甚至绝收,给茶叶生产带来经济损失。为了充分利用茶树冻害叶资源,挽回"倒春寒"带来的不利影响,本研究以茶树冻害鲜叶为原料,分别采用传统烘青工艺、冷冻干燥工艺、冷冻干燥+室温敞口24 h工艺、冷冻干燥+烘干工艺、冷冻干燥+汽蒸工艺、冷冻干燥+真空干燥工艺制备茶样,通过对所制茶样进行感官审评和品质成分分析,评价不同工艺的应用效果。结果表明,传统烘青工艺制得茶样干茶色泽红褐,汤色橙黄,叶底红梗红叶,完全失去了绿茶的品质特征;冷冻干燥工艺制得茶样干茶色泽翠绿、汤色浅黄绿,但香气青气明显、滋味青涩;冷冻干燥+室温敞口24 h工艺、冷冻干燥+烘干工艺和冷冻干燥+汽蒸工艺制得茶样汤色均出现红变;冷冻干燥+真空干燥工艺制得茶样,干茶色泽翠绿,汤色浅黄绿明亮,枣香明显,滋味甜醇,叶底浅黄绿,符合绿茶的品质特征。冷冻干燥+真空干燥工艺制得茶样水浸出物、茶多酚、咖啡碱、游离氨基酸、可溶性糖含量分别为41.00%、18.37%、2.75%、2.84%、1.50%。
The yield of early spring tea trees suffered from freezing damage will reduce or even lost,which brings economic losses to tea production.To make full use of freezing leaves and save the negative influence brought by late spring coldness,tea samples were made by six processing technologies,including traditional baked green processing technology,freeze-drying processing technology,exposing at room temperature for 24 h after freeze-drying processing technology,freeze-drying and drying processing technologies,freeze-drying and steaming processing technologies and freeze drying and vacuum drying processing technologies in the study.Through the sensory evaluation and quality component analysis of the tea samples,the application effects of different processing technologies were evaluated.The results showed that the tea sample produced by traditional baked green processing was red and brown in color,orange and yellow in liquor color,and had red stem and red leaves at the bottom,which completely lost the quality characteristics of green tea.The tea sample obtained by freeze-drying processing technology were green in color and light yellow green in liquor color,but the aroma was obvious and had acerbity taste.The liquor color of tea samples processed by exposing at room temperature for 24 h after treated by freeze-drying technology,freeze-drying and drying technology and freeze-drying and steaming technology showed red changes.The tea sample obtained by freeze-drying and vacuum drying processing technology was green in color,light yellow green and brightness in liquor color,obvious jujube,sweet and mellow in taste,and light yellow green in leaf base,which conformed to the quality characteristic of green tea,whose aqueous extract,tea polyphenols,theine,free amino acid and soluble sugar contents were 41.00%,18.37%,2.75%,2.84% and 1.50%,respectively.
作者
王舒婷
曲凤凤
张新富
胡建辉
Wang Shuting;Qu Fengfeng;Zhang Xinfu;Hu Jianhu(College of Horticulture,Qingdao Agricultural University,Qingdao 266109,China)
出处
《山东农业科学》
2020年第7期137-141,共5页
Shandong Agricultural Sciences
基金
山东省自然科学基金面上项目“复幼处理提高茶树不定根发生的代谢物基础及多基因作用机制”(ZR2019MC039)。
关键词
倒春寒
绿茶
加工工艺
Late spring coldness
Green tea
Processing technology
