FermFast Whiskey Distillers Yeast is used to ferment mashed grains or malt extract worts up to a maximum of 15% ABV. Cannot be used with sugar solutions without separate nutrient addition. This distillers yeast contains glucoamylase for the conversion of dextrins to fermentable sugars. Makes up to 6.6 gallons. Urea Free. 30 Grams.