Comparative Study on the Broken Black Tea Processing Suitability of Different Tea Varieties in Spring and Summer

In this study, 39 tea tree varieties from the same plantation were employed, and their fresh spring and summer leaves were harvested and processed into broken black tea (BBT) using a standardized manufacturing process. The sensory quality and major physicochemical indicators were examined, and their correlations were analyzed. The quality differences between BBT produced from spring and summer raw materials from different varieties were clarified using multivariate statistical analysis. The results indicated that different varieties and seasons significantly impacted the quality of BBT. The sensory evaluation scores of BBT in spring (82.2-92.7 points, averaging 88 points) were generally higher than those in summer (81.1-91.2 points, averaging 87 points). The coefficients of variation for color, aroma, taste, and overall scores were higher in spring tea than in summer tea, indicating that the inter-varietal variation in BBT quality was greater in spring than in summer. Spring BBT exhibited higher average contents of tea polyphenols, theaflavins, thearubigins, and amino acids compared with summer BBT, while the opposite was observed for theabrownins and soluble sugars. Correlation analysis revealed that a significant positive correlation between tea polyphenol content and sensory quality was observed for both spring and summer tea. In contrast, the sensory quality of spring and summer BBT exhibited a negative correlation with the contents of soluble sugars and amino acids, respectively. A comprehensive evaluation system was developed using principal component analysis (PCA) and multiple regression analysis (MRA) to classify the tea varieties into three categories based on their BBT processing suitability: suitable for both spring and summer (e.g., Enchahong and Jiukengzao), season-dependent (e.g., Meizhan and Huangdan), and poorly suitable (e.g., Longjing 43, Baiye 1, and Fuyun 6). These findings provide a theoretical basis and practical guidance for variety selection and seasonal matching in BBT production.