100% Pure Food Grade Calcium Chloride (e509) for use in spherification and molecular gastronomy. Calcium Chloride (E509) is a salt of calcium and chlorine. It is used as a sequestrant and firming agent. Calcium chloride is one of the primary ingredients in direct spherification. It is used in the setting bath to activate the sodium alginate. Due to it's extremely salty taste, it should not be used in reverse spherification. Add a small amount of calcium chloride to each jar of pickles or sauerkraut. Calcium chloride is designated generally recognized as safe (GRAS) by the U.S. Food and Drug Administration. Because of its hygroscopic nature, anhydrous calcium chloride must be kept in tightly-sealed air-tight containers.