Integrated sensory, volatilomic and metabolomic profiling reveals storage-stage-associated quality evolution of raw...

During long-term storage, raw Pu-erh tea (RAPT) undergoes substantial sensory and chemical changes. However, the integrated contributions of sensory attributes and metabolites to this process are not well understood. This study applied an integrated multi-omics approach to examine its quality evolution across storage stages. Sensory evaluation indicated a notable shift in aroma profile, from initial floral and fruity notes to matured characteristics dominated by woody, stale, and herbal scents. Metabolomic analysis showed that during storage, total polyphenols (TPs), catechins, theanine, and free amino acids (FAA) decomposed, while total flavonoids accumulated. Additionally, 332 metabolites were identified as potential markers for distinguishing aging/aged RAPT. Eight key aroma markers of the aging process were identified using volatilomics, including 1,2-dimethoxybenzene, 1,2,3-trimethoxybenzene, linalool oxide-related isomers and cedrol. Collectively, this study advances our understanding of the chemical and sensory evolution of RAPT during storage and provides a foundation for optimizing storage strategies to control product quality.