The Brettanomyces bruxellensis contamination of wines: A case study of Moldovan micro-winery

Abstract

Brettanomyces bruxellensis yeasts cause wine spoilage by producing volatile phenol compounds with specific off-odors. Assessing the propagation of this species is challenging, especially for micro-wineries. In this study, wines produced in a micro-winery from the grapes of different varieties collected from three PGI regions of Moldova over three years were studied for the presence and infection level of Brettanomyces spoilage yeasts, using traditional microbiological and molecular methods. The results of Brettanomyces infection monitoring in mature wines might speak in favor of the hypothesis that grape berries can be a potential source of B. bruxellensis in wine. The contamination levels of mature wines with respective species fluctuated in accordance with the year of grape cultivation, being the highest during the 2023 vintage. This study shows the potential of applying sequencing analysis for tracking the source of Brettanomyces contamination in wineries.