Abstract:The black tea produced from three tea tree cultivars, namely Foxiang, Yunkang No.10, and Yunchahong, were used as research objects. Storage quality differences were evaluated under two drying methods (oven-drying and sundrying) and three storage durations (0, 6, and 12 months). Key internal components were analyzed, and sensory evaluation was conducted to explore the quality differences between Congou black tea produced from different tea tree cultivars and under different drying methods and storage durations. The results showed that the moisture content and water extract content of black tea decreased during 0~6 months and increased from 6 to 12 months of storage. The content of phenol ammonia ratio, theaflavins, and tea polyphenols increased during 0~6 months of storage but decreased thereafter. Oven-dried black tea demonstrated better quality than sun-dried black tea during storage, and the sensory quality of dried black tea made from fresh leaves of Yunchahong stored for 12 months was the best. The regulatory effects of moisture, water extracts, tea polyphenols, and theaflavins on the formation of flavor substances in black tea during storage are greatly influenced by cultivars and drying methods. Principal component analysis showed that the dried black tea from the fresh leaves of the Yunkang No.10 cultivar stored for 12 months ranked first in terms of overall internal quality. Multiple regression analysis showed that water content, water extracts, soluble sugars, and flavins could significantly predict the quality changes of black tea during one year of storage. These findings highlight significant differences in storage quality attributable to the tea cultivar and drying method, providing a theoretical basis for the processing and storage of Dianhong Congou tea.
