Dynamic interplay of p-coumaric acid metabolism, microbial succession, and volatile flavor dynamics in strong aroma-type Baijiu fermentation: A multi-omics perspective

p -Coumaric acid ( p -CA), a bioactive phenolic compound pivotal for flavor complexity and health-promoting properties in Baijiu, lacks mechanistic insights into its dynamic formation during fermentation. This study integrates multi-omics approaches to unravel the spatiotemporal interplay of p -CA metabolism with microbial succession and physicochemical shifts in Strong aroma-type Baijiu. Early-stage (0-12 days) p -CA accumulation relied on aerobic hydrolysis of lignocellulosic substrates via ferulic acid esterase, while late-stage (12-85 days) biosynthesis transitioned to anaerobic pathways dominated by Acetilactobacillus -mediated acidification (pH 3.5-4.5), enabling anaerobic bacteria ( Bacteroidales , Bacteroidota ) to synthesize p -CA via phenylalanine ammonia lyase (PAL). Metagenomics highlighted upregulated PAL genes in high- p -CA phases, whereas volatile esters/alcohols negatively correlated with p -CA due to phenylalanine competition. These findings establish microbial community succession as the central driver of p -CA dynamics, offering actionable strategies to optimize phenolic acid and flavor profiles through microenvironmental and microbial regulation. • Early p -CA (0-12 days) comes from microbial cell wall hydrolysis. • Late p -CA biosynthesis is influenced by Acetilactobacillus -produced organic acids. • Unclassified anaerobes ( Bacteroidales, Bacteroidota ) correlate with p -CA. • Enzymes (ferulic acid esterase, PAL ) drive p -CA release. • p -CA is synthesized by microorganisms by metabolizing phenylalanine in Baijiu.