Antifoam Liquid, AF-72Antifoam, liquid, AF 72. A food grade silicone oil emulsion that reduces surface tension and therefore reduces frothing in your fermenting wine. Use about 3 to 5 drops in a carboy before fermentation becomes violent, then 2 to 3 drops if foaming occurs later. The smaller the surface area the more effective it is. For use in home and commercial wine making. Multiple sizes available. Select your desired size. See Commercial Supplies for larger sizes.