Saccharomyces cerevisiae: A key yeast for the wine-making process

Abstract

Saccharomyces cerevisiae is the most important yeast species involved in wine fermentation. Traditionally, this species has been used as a starter culture to conduct the alcoholic fermentation due to its optimal fermentative properties. For this reason, nowadays S. cerevisiae is commercialized as an active dry yeast and used in wineries worldwide to improve the fermentative processes and wine quality. However, over the last years it has been reported that wines fermented by commercial strains lack sensory attributes of typical regions of a country. Thus, the selection of S. cerevisiae indigenous strains is being promoted to preserve typical quality and flavor of regional wines.Moreover, S. cerevisiae could act as a biocontrol agent producing killer toxins during wine-making process. Killer strains are able to inhibit the growth of spoilage microorganisms that affect wine quality. The addition of sulfur dioxide as an antioxidant and antimicrobial additive is a common practice during wine production. However, due to current trends to reduce the use of chemical additives, the utilization of starter cultures producers of killer toxins is an interesting alternative to avoid the contamination by spoilage yeasts. Therefore, the inclusion of S. cerevisiae killer yeasts with appropriate fermentation properties is essential to accomplish controlled fermentations, pointing out the importance of a clever selection of strains.