Analysis of key compounds and flavor differences across four Liupao tea aroma types via flavoromics and molecular docking

ABSTRACT HS-SPME-GC/MS and UPLC were used to profile volatiles and non-volatiles in four Liupao tea aroma types (betelnut, stale, ginseng, and jujube). Combined flavoromics and molecular docking clarified aroma differentiating metabolites and their sweet taste binding mechanisms. In total 1509 volatiles across 15 classes were detected; terpenes, esters and ketones dominated. 47 key aroma compounds (ROAV≥100) distinguishing the four types were screened via OPLS-DA. Nonvolatile catechin, gallic acid and theobromine also mediated flavor divergence, with Mantel tests revealing synergistic correlations between catechin compounds and key volatiles. The 12 volatile compounds mainly bind to the T1R2 and T1R3 sweet taste receptors by Van der Waals and electrostatic interactions. Terpenoid and amino acid metabolic pathways dominated aroma differentiation. This work identifies type specific key metabolites and their molecular flavor-forming mechanisms to support Liupao tea aroma classification.