Analysis of regional flavor quality differences in congou black tea using metabolomics.

Congou black tea, a traditional Chinese tea, shows regional variations in flavor and aroma. This study employed metabolomics techniques to compare Congou black tea from Zhejiang, Fujian, Sichuan, and Jiangxi. Using HS-SPME-GC-MS and SPME-GC-IMS, we identified 110 and 60 volatile organic compounds, respectively, with 5 common VOCs. Statistical analysis revealed 45 and 20 differential VOCs (VIP > 1, P < 0.05), essential for distinguishing the regions. The predominant compounds in FJ, SC, ZJ, and JX were esters, hydrocarbons, and ketones, respectively. UPLC-MS/MS analysis identified 180 non-volatile compounds, with SC showing a greater abundance of chemicals. KEGG pathway analysis revealed four common pathways and annotated 11 metabolites. These findings provide insights into the regional flavor differences in Congou black tea and highlight key factors influencing its quality.