Food grade glycerin is used to increase mouth-feel of wine and increase smoothness. It should be added just prior to bottling. Use between 1 and 3 tablespoons of Glycerin for each gallon of wine, or between 2 and 8 ounces of Glycerine for each 5 gallons of wine, depending on your taste. When adding to cordials, use 1 to 2 tablespoons per each quart.