Investigation of rose-honey aroma formation during tea infusion fermentation by Z09 through GC-MS and GC-IMS.

Tea aroma critically influences consumer preference. Z09, isolated from Yunnan sun-dried green tea, enhances the rose-honey aroma of fermented tea infusion. This study investigated aroma formation during liquid-state fermentation using GC-MS, GC-IMS, and molecular docking. GC-MS and GC-IMS identified 223 and 74 volatile organic compounds (VOCs), respectively, including alcohols, ketones, and esters. Six key aroma-active compounds were identified via relative odor activity value (ROAV), while orthogonal partial least squares discriminant analysis (OPLS-DA) revealed 49 differential VOCs driving aroma evolution. By integrating ROAV, OPLS-DA, abundance analysis, and molecular docking, 29 major VOCs were linked to the rose-honey profile, with phenylethyl alcohol as the dominant contributor. Their binding to olfactory receptors involved noncovalent interaction. A flavor wheel was constructed to visualize the aroma profile. This study is the first to elucidate how bacteria influence the aroma of tea infusion through liquid-state fermentation, offering insights for the development of specialty tea products.