Tracking the evolution of volatile aroma compounds in Baijiu during storage: quantitative insights into temperature, oxygen, and pottery influences.

This study elucidated microenvironmental regulation of aroma compound evolution in Baijiu through a multifactorial aging study. Quantitative analysis of 139 volatile compounds employed multimodal extraction coupled with GC-MS/GC × GC-TOFMS. PLS-DA indicated significant sample divergence across factors. Spearman correlation/network visualization revealed pottery-associated modulation of 54 compounds, temperature-driven dynamics in 47 compounds, and oxygen-dependent regulation of 18 compounds. Elevated storage temperature significantly reduced esters, terpenes, aldehydes, and ketones, while elevated dissolved oxygen accelerated ester degradation and sulfur compound interconversions. High temperature (>35 °C) promoted ester hydrolysis and the reduction of aldehydes and ketones; oxygen selectively oxidized methanethiol to dimethyl disulfide and dimethyl trisulfide. Storage with pottery chips enhanced accumulation of furans, pyrazines, and sulfur compounds, likely catalyzed by clay-derived metal ions. Variance partitioning analysis identified storage duration (10 %), followed by temperature (9 %), pottery (4 %), and oxygen (1 %). The hierarchical framework clarifies multifactorial modulation of aroma evolution, offering technical insights for optimizing artisanal spirit aging.