Citation: Prepared by Maureen Moroney, research scientist, and Jennie Savits, enology program specialist, Midwest Grape and Wine Industry Institute at Iowa State University. Reviewed by Aude Watrelot, assistant professor of enology, Iowa State University Department of Food
Science and Human Nutrition.
Abstract: Wines bottled with residual sugar concentration at or above 1 gram per liter have the potential to be at risk for yeast refermentation. Stringent cleaning and sanitation practices, appropriate sulfur dioxide (SO2) use, and sterile filtration prior to bottling help to prevent refermentation issues. For more information on refermentation, see Iowa State University Extension and Outreach publication FS40–Wine Fault Series: Refermentation, store.extension.iastate.edu/product/15980. Additionally, the use of sorbic acid or its potassium salt (potassium sorbate) is permitted as a preservative by the Alcohol and Tobacco Tax and Trade Bureau (TTB). The additive inhibits yeast (primarily Saccharomyces cerevisiae) and molds. Its effectiveness
depends on factors such as pH and alcohol content; and should be used in conjunction with appropriate SO2 additions and wine clarification methods.