Frostline Vanilla Lactose Free Soft Serve is a dry mix that is reconstituted with tap water and frozen down in a soft serve machine. Pour the mixture directly into a soft serve machine or cover and place in refrigerator for later use. When mixed with 2 gallons of water, yield is 2.5 gallons per bag (15 gallons per case). Number of 4 oz servings per bag. Number of 4 oz servings per case when mized with 2 gallons of water: 540.