The Winemakers Research Exchange is a non-profit organization of Virginia winemakers pursuing quality improvement through practical experimentation in vineyards and wineries.
Experimental results are evaluated using appropriate chemical measures. Sensory sessions allow for blind tasting and group discussion of each project.
Sulfur dioxide is a traditional, inexpensive additive used widely at many different stages of modern wine making to combat oxidation and microbial spoilage. It is used pre-fermentation to control microbial populations that come in on grapes and the oxidation of juice and post-fermentation (to protect wine from oxidation and spoilage during aging. SO2 is also used for storage of barrels to prevent microbial spoilage and as a general cleaning agent in the winery (sprays on surfaces, etc…).
Despite its widespread use, many practical questions remain, including when and how much SO2 to add. In this newsletter we review the chemistry, efficacy and practical use of SO2 in the winery and present studies done by Kirsty Harmon of Blenheim Vineyards exploring these very questions.