烘青绿茶苦涩味及其滋味贡献物质分析

对烘青绿茶苦涩味量化分析及其主要滋味贡献物质进行探讨。以不同嫩度烘青绿茶为原料,采用量化感官分析方法及化学分析手段分析了茶汤滋味分属性（包括苦味、涩味、鲜味和醇味等）和滋味化学成分含量,并建立了两者之间的相关性。研究结果表明,随着烘青绿茶嫩度的下降,其茶汤苦味、涩味和鲜爽味强度呈下降趋势,整体滋味品质也显著下降。通过分析茶叶滋味化学成分含量及其滋味Dot值,发现烘青绿茶苦味的主要贡献物质是EGCG和咖啡碱;而涩味的主要贡献物是儿茶素和黄酮苷,其中儿茶素以EGCG为主,包括EGC和ECG,黄酮苷以槲皮素-3-O-芸香糖苷（Que-rut）和槲皮素-3-O-半乳糖苷（Que-gala）为主,包括杨梅素-3-O-半乳糖苷（Myr-gala）、槲皮素-3-O-葡萄糖苷（Que-glu）、牡荆素-2"-O-鼠李糖苷（Vit-rha）、山柰酚-3-O-半乳糖苷（Kae-gala）、山柰酚-3-O-芸香糖苷（Kae-rut）、山柰酚-3-O-葡萄糖苷（Kae-glu）等。Dot值分析表明氨基酸对烘青绿茶鲜爽味没有显著贡献。本研究初步明确了烘青绿茶苦涩味的主要贡献物质,为茶叶品质提升和滋味化学研究提供理论基础。

Analysis of the Bitter and Astringent Taste of Baked Green Tea and Their Chemical Contributors

The paper discussed the quantitative analysis of the bitter and astringent taste of the baked green tea and the main chemical component contributors. Baked green teas made of fresh tea leaves with different tenderness were used as the raw material to analyze the taste attributes (including bitterness, astringency, umami, and mellowness) and contents of quality components by quantitative sensory evaluation and chemical analysis, and synchronously establish the correlation between them. The results showed that, with the decrease of tea leaves tenderness, the bitter, astringent and umami taste of the tea infusions decreased as well as the total taste quality. Through analyzing the quality components and their taste contributions, it was found that the main contributors for the bitterness of the baked green tea were EGCG and caffeine, and for the astringency were catechins and flavonoid glycosides. EGCG
was the main catechin component for astringent taste, and EGC and ECG also had significant contribution. Que-rut and Que-gala were the main flavonoid glycosides, other glycosides including Myr-gala, Que-glu, Vit-rha, Kae-gala, Kae-rut, Kae-glu also had significant contribution for astringent taste. The analysis of the Dot values showed that free amino acids had no significant contribution to the umami tatste. This research preliminarily illuminated the main chemical contributors for the bitter and astringent taste of the baked green tea and provided theory basis for the tea-quality improvement and taste-chemistry study.