Dynamic changes in chemical components, volatile profile and antioxidant properties of Xanthoceras sorbifolium leaf tea during manufacturing process

In order to elucidate the dynamic changes of quality characteristics in Xanthoceras sorbifolium leaf tea (XLT), this work investigated the chemical components, volatile profile, and antioxidant properties at key stages of fixation, shaping, and drying. The process of fixation and drying emerged as critical stages that affected the chemical components and taste of XLT. Total polyphenols, reducing sugars and chlorophyll were the differential compounds, which decreased by 29.1 %, 63.3 % and 69.5 % during processing, respectively. Threonine, glycine, arginine, reducing sugar, caffeine, catechin (C), and epicatechin gallate (ECG) were primary taste characteristic compounds. A total of 95 volatile organic components (VOCs) and 24 key odorants with relative odor activity value (ROAV) > 1.0 were identified in XLT, ethyl 2-methylbutanoate-D, dimethyl disulfide, and ethyl isobutyrate (ROAV = 100) were the central contributors to volatiles profile. Moreover, tea manufacturing enhanced the antioxidant potency composite (APC) by 1.1 %, primarily due to its high water extract content.