Dynamic variations in flavor profiles of Guizhou high-mountain white tea produced by Eurotium cristatum using solid-state fermentation

To enrich the processing products of Guizhou high-mountain white tea, this study employed sensory evaluation, headspace solid-phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC-MS), and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) techniques to investigate the evolving flavor profiles of Guizhou high-mountain white tea fermented with Eurotium cristatum . The resulting infusions displayed a dark brown color and a significant reduction in bitterness and astringency following fermentation. Furthermore, a total of 104 and 120 volatile organic compounds (VOCs) were identified using the HS-SPME-GC-MS and HS-GC-IMS methods, respectively. Among these, 13 VOCs, including methyl salicylate, linalool oxides, and linalool, exhibited relative odor activity values (ROAVs) exceeding 1. These compounds, linked to floral and peppermint aromas, significantly impacted the aroma profiles of the fermented white tea. Additionally, orthogonal partial least squares-discriminant analysis (OPLS-DA) identified 24 VOCs that were primarily responsible for distinguishing the various fermentation stages, adhering to a more stringent criterion with variable importance projection (VIP) values > 1.30 and p  < 0.05. Therefore, this study confirms that solid-state fermentation utilizing Eurotium cristatum is a promising method for effectively reducing bitterness and astringency while enhancing the floral aroma of white tea.