Spoilage Yeasts in Red Wines

Abstract

Abstract The production of wine depends on the desirable fermentative activity of microorganisms. However, other microorganisms are also responsible for unwanted spoilage. The factors promoting the dissemination of spoilage yeasts from grapes to wines are presented from an ecological perspective, demonstrating that the knowledge of vineyard and winery ecosystems is essential to establish their origin, routes of contamination, critical points of infection, and ultimately their control. In red wines, the most relevant species is Brettanomyces/Dekkera bruxellensis, producing off-flavors in red wines due to volatile phenols. Refermentation in bottled wines is mostly due to Saccharomyces cerevisiae and Zygosaccharomyces bailii. The occurrence of most of these hazards may be prevented by appropriate technological measures, like filtration, thermal treatments and sulfur dioxide addition. Other preservatives (e.g., dimethyldicarbonate, chitosan) may also be used with different degrees of efficiency. Regarding B. bruxellensis, routine microbiological monitoring and volatile phenol quantification during wine aging are essential to detect the presence of active populations that must be inactivated before or during bottling.