Flavor evolution of Pu-erh tea (ripe tea): Quantitative characterization of volatile dynamics during natural aging

This study investigated the flavor evolution of RPT during natural aging using GC-MS and metabolomics approaches. We identified 114 volatile compounds and performed quantitative analysis. Metabolic pathway analysis implicated three pathways caffeine metabolism, toluene degradation, naphthalene degradation as potential sources of methyl group precursors for the formation of methylated aroma compounds, particularly methoxybenzenes. These findings indicate that methylphenols serve as essential intermediates in the biochemical transformations that produce methylated compounds during aging. Additionally, three compounds are suggested as precursors for methylphenols compounds: 2,4,6-tritert-butylphenol, 2,5-ditert-butylphenol, and butylated hydroxytoluene. This study advances our understanding of aroma evolution in RPT during natural aging, highlighting the critical role of methylphenols as key intermediates in these chemical transformations. The identification of these phenolic compounds provides a foundation for targeted strategies to enhance flavor development in Pu-erh tea.