Diversity in Spoilage Yeast Dekkera/Brettanomyces bruxellensis Isolated from French Red Wine. Assessment During Fermentation of Synthetic Wine Medium

Abstract

Yeast Brettanomyces bruxellensis is a contaminant found worldwide and is responsible for red wine spoilage due to the development of animal and phenolic off-odours. During this study, 24 Brettanomyces bruxellenis isolates were obtained from red wine samples from two French wineries and these were discriminated as 23 strains. Nine strains coming from 2 wineries and 4 vintages were cultivated in synthetic wine medium for 1500 hours and they gave nine different behaviours. Four main growth patterns (with different growth steps and durations) and three main different sugar consumption profiles were obtained. Glucose and fructose were not limiting substrates for all strains. The production level of 4-ethylphenol was found to vary from strain to strain (from 0.350 to 2.773 mg L-1) and was independent of the biomass concentration. Some strains presented a coupled-togrowth production of volatile phenols, others did not. This study showed that different strains of Brettanomyces bruxellensis behaved differently, one from another, under the given conditions taking into consideration several aspects. The results thus demonstrate a large intraspecific diversity.