Stera-Sheen is one of the most widely used sanitizers in the frozen dessert industy, and for good reason. Not only is it FDA approved and NSF listed as a no-rinse sanitizer, it also delimes, and removes milkstone from your machine and parts.  It is effective to use in areas with hard water, and will keep your machine looking like new given that is it noncorrosive and will not stain or damage metal, plastic, glass, or rubber.