Inactivation of Dekkera bruxellensis yeasts in wine storage in brand new oak barrels using low electric current technology

Abstract

Dekkera bruxellensis is one of the species of yeast, which is most damaging to wine quality, and the tools available to control its growth are limited. In previous studies, non-Saccharomyces yeasts and Dekkera bruxellensis have been significantly restricted during wine-making processes using an innovative approach based on low electric current treatment (LEC). In the present study, LEC techniques were assessed for their capacity to inhibit wine spoilage by D. bruxellensis and to prevent formation of undesirable flavours during storage in oak barrels. Although the effect of SO2 treatment on D. bruxellensis viability and ATP content was more immediate, from the 30th day onward no significant variations between LEC and SO2 treatments were observed. At the end of the trial, LEC treatment had had a comparable effect to that of SO2 addition. Acetic acid content was significantly lower after LEC and SO2 treatments than in untreated wines and volatile phenols were also found to be significantly lower in the LEC treated wine. Moreover, the results from the panel test clearly indicate that no significant differences were found between the LEC and the SO2 treated wines. These results clearly indicate that LEC technology could represent a viable tool to limit yeast spoilage caused by D. bruxellensis. The present work represents, to our knowledge, the first attempt to control D. bruxellensis during red wine storage in oak barrels using LEC. The potential industrial applications of LEC technology include the real future possibility of producing a new, marketable range of healthier wines to satisfy the requirements of modern wine consumers.