Sodium Metbisulfite

Sodium metabisulfite is a white or yellowish crystalline powder. It is a salt of sulfurous acid, made by reacting sulfur dioxide with a solution of sodium carbonate or sodium hydroxide. It is commonly used as a disinfectant, antioxidant, and preservative.

Manufacturers add sodium metabisulfite to foods to prevent browning and spoilage, acting as a preservative and antioxidant. It is often found in dried fruits, wines, processed potatoes, and some baked goods to maintain color and freshness.

Sodium metabisulfite is generally recognized as safe (GRAS) by the FDA when used as a preservative. It can cause allergic reactions in some individuals, particularly those with asthma or sulfite sensitivity, leading to symptoms like hives or breathing difficulties. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has evaluated sulfites, including sodium metabisulfite, and established acceptable daily intakes. Evidence for other health concerns is mixed and not conclusive.