Effectiveness of dimethlydicarbonate to prevent Brettanomyces bruxellensis growth in wine

The aim of this study was to investigate the anti-microbial properties of the dimethyldicarbonate (DMDC) towards the wine spoilage yeast Brettanomyces bruxellensis at different winemaking stages. DMDC anti-microbial activity was estimated in red must for diverse wine microorganisms including different strains of B. bruxellensis. DMDC effect before alcoholic fermentation, before malolactic fermentation, and in finished wine were investigated. DMDC was also tested on lees. Microbial monitoring was done by epifluorescence observation and plate numeration. The identification of yeast species and the specific detection of B. bruxellensis were performed with molecular tools. DMDC stopped B. bruxellensis growth at different winemaking stages. But it could also act on fermenting species like Saccharomyces cerevisiae and Oenococcus oeni. Therefore, its use before the end of fermentations should be avoided. On the other hand, the DMDC action was shown to be transitory. Therefore, single addition during ageing could be insufficient. Finally, DMDC could be used just before bottling as an ultimate anti-microbial tool.