Comparison of flavor profiles, antioxidant capacities, and metabolite profiles among three Golden Flower Loose Teas: a multi-technique study

Golden flower loose tea (GFLT), produced by inoculating E. cristatum , is a distinctive category of fermented tea. This study is the first to systematically compare GFLTs derived from black, green, and white tea substrates (GFLBT, GFLGT, GFLWT) under identical solid-state fermentation conditions. A multi-technique approach integrating E-tongue, GC-MS, GC-IMS, UHPLC-HRMS/MS, molecular docking, and multivariate statistics was employed. Marked differences were observed: GFLBT was characterized by pronounced sweet and bitter tastes accompanied by a honey aroma, whereas GFLGT and GFLWT exhibited stronger astringent and umami tastes, floral aroma, and higher antioxidant capacity. ROAV analysis and PLS-DA models identified 7 key differential volatile metabolites, including trans - β -ionone and 2,3-diethyl-5-methylpyrazine. Molecular docking elucidated their interactions with 6 human broad-spectrum olfactory receptors, providing mechanistic insights into aroma perception. UHPLC-HRMS/MS further revealed that the differential non-volatile metabolites among the three GFLTs were mainly enriched in flavonoid and amino acid metabolic pathways. Collectively, these findings characterize substrate-dependent variations in the quality formation of GFLTs and provide a scientific basis for the value-added utilization of summer-autumn tea resources. • GFLBT featured β -damascenone-driven honey aroma and pronounced sweetness. • GFLGT and GFLWT showed strong floral aroma, umami taste with antioxidant activity. • trans - β -Ionone exhibited strongest binding (-7.56 kcal/mol) to OR1A1. • E. cristatum fermentation regulated flavonoid and amino acid metabolic pathways.