The influence of polyphenol supplementation on ester formation during red wine alcoholic fermentation

Pre-fermentative polyphenol supplementation in industrial scales (100-hL) and simulated fermentation (350 mL clarified juice) were conducted. Results showed that in practical winemaking, adding QCE (quercetin, caffeic acid and ellagic acid) increased acetate concentrations in wines and extra grape seed tannins (T) enhanced the effect of QCE supplementation. In simulated fermentation with clarified juice, the synergy effect of QCE and T was evidenced that ester formation was only promoted through mixed QCET supplementation. Besides, QCE supplementation benefited the formation of 4-vinylcatechol adducted malvidin-3-O-(acetyl/coumaroyl)-glucoside and decreased other anthocyanin derivatives derived from pyruvic acid and acetaldehyde, leading more pyruvic acid and acetaldehyde left in yeast to enhance the metabolic fluxes of esters. Findings manifested the connection between the formation of esters and anthocyanin derivatives during red wine alcoholic fermentation, which would be influenced by the phenolic matrix. This work could provide a perspective in winemaking industry for modulating aroma profile via polyphenol supplementation.