Effect of different drying temperature settings on the color characteristics of Tencha

Color is critical factor in the commercialization of Matcha. In this study, sensory evaluation, color difference analysis, as well as targeted and non-targeted analyses were employed to investigate the impact of different drying temperature settings on the color characteristics of Tencha. The findings revealed that compared to a single drying temperature setting, a two-stage or multi-stage drying process more effectively preserved the color quality of Tencha. Specifically, a setting involving an initial period of high-temperature drying followed by low-temperature drying (samples T_6, T_7, T_10, and T_13) resulted in superior tea color quality, characterized by higher chlorophyll content and lower levels of lutein and <i>β</i>-carotene. Chemometric analysis identified chlorophylls and their derivatives (chlorophyll <i>a</i>/b, pheophytin a/b, pyropheophytin a/b) as the key factors influencing Tencha's color. These results can provide valuable insights for optimizing tea processing methods to enhance quality.