Pro-Cure Metabisulfite for curing salmon eggs is 99% pure and a tremendous preservative that works well on eggs! While extensively used as a food preservative in other industries, Pro-Cure advises using sodium metabisulfite sparingly as it is very 'hot' - too much will melt your eggs or turn them into cement. Used correctly, Pro-Cure Sodium Metabisulfite sustains flavor and maintains color, extending the shelf-life of your salmon eggs. Sodium metabisulfite is a salt of sulfurous acid Preservative for eggs, but use caution - too much ruins your batch Salmon love the flavor of metabisulfite 32 oz. bottle Made in the USA