影响工夫红茶茶汤亮度的关键成分分析

为探索影响工夫红茶茶汤亮度的关键成分，以专家人工感官评审为依据，根据亮度对26?个工夫红茶茶汤进行分组（高亮、中亮、暗），随后对茶汤中24?个组分进行定量分析，并通过统计分析手段筛选出与茶汤亮度显著相关的小分子化合物。然后对不同分子质量范围的茶汤馏分进行超滤分离，初步确定影响茶汤亮度的大分子馏分，并通过复原与添加实验进一步加以验证。结果表明：通过多变量分析和单因素方差分析，筛选出茶黄素-3-没食子酸酯、没食子儿茶素没食子酸酯、咖啡碱在高亮茶汤中显著增高，没食子儿茶素在高亮茶汤中显著降低。对不同截留分子质量（molecular mass cut-off，MMCO）茶汤馏分的超滤分离和添加验证实验，发现MMCO高于100?kDa的茶汤大分子馏分不利于高亮茶汤的形成。本研究发掘了影响工夫红茶茶汤亮度的关键成分，对后续高亮工夫红茶的品质调控和定向加工具有重要的理论指导意义。

Key Chemical Components Influencing the Brightness of Congou Black Tea Infusions

This study aimed to explore the key chemical components that can affect the brightness of Congou black tea infusions. Firstly, 26 Congou black tea infusions were classified into three groups (high-brightness, mid-brightness and dark) based on the brightness evaluated by a professional sensory panel. Then, 24 components in tea infusions were quantitatively analyzed, and the small molecular compounds significantly related to the brightness of tea infusions were selected by means of statistical analysis. Finally, the tea infusions were fractionated by ultrafiltration and the macromolecular fractions affecting the brightness of tea infusions were determined and further validated by reconstitution and addition experiments. The results of multivariate analysis and one-way analysis of variance (ANOVA) showed that theaflavin-3-gallate (TF-3-G), gallocatechingallate (GCG) and caffeine (CAF) were significantly increased in tea infusions with high brightness, while gallocatechin (GC) was significantly decreased. Moreover, it was found that the macromolecular fraction greater than molecular mass cut-off (MMCO) of 100 kDa negatively affected the formation of bright tea infusions. The results of this study will be of theoretical significance for guiding the quality control and directional processing of Congou black tea in the future.