Dual roles of polyphenols in modulating red wine aroma: From yeast-derived aroma accumulation to matrix effects on aroma release.

Polyphenols are well recognized for their roles in wine color and mouthfeel, yet their comprehensive influence on aroma modulation remains poorly understood. Here, a dual-system approach was employed, combining a synthetic grape must fermentation model analyzed by headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME/GC-MS) with a wine matrix system analyzed by static headspace gas chromatography-mass spectrometry (SHS/GC-MS). During synthetic must fermentation, polyphenol supplementation enhanced fermentation kinetics without inhibiting yeast growth, and promoted the accumulation of fatty acid ethyl esters including ethyl hexanoate, ethyl octanoate, and ethyl decanoate. Within the wine matrix, polyphenols exerted structure-dependent effects on ester volatility, suppressing short-chain and acetate esters while enhancing the release of longer-chain ethyl esters. Sensory evaluation across both systems revealed a consistent shift toward a red wine-like aroma profile. These findings demonstrate that polyphenols dually modulate both biosynthetic accumulation and physicochemical release of fruity esters, collectively shaping red wine aroma typicity.