Indagine su tecniche innovative per ridurre la concentrazione di etilfenoli in sistemi modello

Ethylphenols, produced by Brettanomyces/Dekkera sp. yeasts, are associated with a serious taste defect in wine called “brett character”. Low electric current (LEC) and activity of laccase from Trametes versicolor were studied with the aim of degrading 4-ethylguaiacol and 4-ethylphenol and their precursors, the ferulic and p-coumaric acids. Both techniques have produced a significant decrease in all the phenolic substances. In the solution treated with 200 mA electric current for 20 minutes the concentration of 4-ethylguaiacol and 4-ethylphenol were decreased by 32.1 and 32.3% respectively vs. the control. Instead, after an incubation at 25°C for 20 minutes, the laccase has produced a decrease in 4-ethylguaiacol and 4-ethylphenol of 55.3 and 44.1%, respectively. Finally, by applying simultaneously the two techniques (LEC and laccase), a synergistic effect has occurred and the ethylphenols and cinnamic acids were degraded completely in only a few minutes.