Metabolomic Characterization of Sun-Dried Green Tea from Different Regions of Xishuangbanna

This study integrated sensory evaluation, volatile profiling (HS-SPME/GC × GC-Q-TOF-MS) and non-volatile profiling (UHPLC-Orbitrap-MS), and multivariate analysis to characterise 13 Sun-Dried Green Tea samples from Xishuangbanna, Yunnan, China. A total of 230 volatile and 226 non-volatile compounds were identified, and metabolite profiles were more similar among geographically adjacent production regions. Based on the intensity of the floral-fruity aroma, the samples were classified into three groups: strong, relatively strong, and pure, with a weak floral-fruity aroma. The strong floral-fruity group, comprising samples from Mengla and vicinity, contained high levels of Nonanal, Decanal, 2-pentylfuran, benzaldehyde, cis-linalool oxide, safranal, and 6-methyl-5-hepten-2-one. The moderately rich floral-fruity group, consisting of high-altitude Menghai samples, exhibited significantly higher levels of limonene, linalool, p-cymene, β-myrcene, γ-terpinene, terpinolene, and α-terpinene, compounds with both floral and woody attributes. Menghai and vicinity samples were characterised by higher levels of proanthocyanidins, hydrolyzable tannins, and amino acids, which account for their pronounced astringency and sweet aftertaste. In contrast, samples from Mengla and the vicinity exhibited higher levels of Myricetin 3-O-glucoside, Isoschaftoside, and Epigallocatechin 3-O-(3-O-methylgallate). Key differential compounds revealed that multiple environmental factors drive distinct metabolite profiles, which may underlie the regional quality difference of Sun-Dried Green Tea. These findings provide a theoretical reference for production improvement and market guidance.