The effect of sulfur dioxide addition at crush on the fungal and bacterial communities and the sensory attributes of Pinot gris wines.

Modern day winemaking often involves the addition of sulfur dioxide (SO) at crush to act as both an antioxidant and an antimicrobial agent. While the effects of SO on microbial communities and particularly on spoilage microorganisms has been well-studied, the advent of culture-independent molecular technologies, such as Illumina sequencing, allows the subject to be re-visited in a new context. High-throughput amplicon sequencing allows for a more thorough evaluation of microbial communities, as thousands of microbial sequences per sample can be identified and even rare microorganisms can be studied.

Sulfur dioxide addition at crush alters Saccharomyces cerevisiae strain composition in spontaneous fermentations at two Canadian wineries.

During winemaking, sulfur dioxide (SO) is often added prior to the onset of alcoholic fermentation to prevent the growth of spoilage microorganisms and to create an environment that promotes the rapid colonization of the grape must by Saccharomyces cerevisiae. Most recent research has focused on the impacts of SO additions on spoilage microorganisms or on the yeast community at a species level, but less is known about the impacts that SO additions have on S. cerevisiae populations.