2.5 Gram Sulfur Discs - 1 lb. Bag for Wine Barrel SanitationProtect your barrels from spoilage with 2. 5 Gram Sulfur Discs. These specialized discs are a essential tool for winemakers looking to maintain the sanitation of empty wooden barrels. When burned inside the barrel, they release sulfur dioxide (SO2) gas, which effectively kills wild yeast, mold, and spoilage bacteria. This "burning" process is the traditional and most effective way to prevents the growth of Acetobacter and Brettanomyces in barrels that