Sodium Metabisulfite

Sodium metabisulfite is an inorganic salt that forms a white, crystalline powder. It is primarily composed of sodium, sulfur, and oxygen. It is typically produced through the reaction of sulfur dioxide with sodium carbonate or sodium hydroxide.

Manufacturers add sodium metabisulfite to foods primarily as a preservative and antioxidant. It helps prevent spoilage by inhibiting the growth of bacteria and molds, and it also prevents discoloration and maintains freshness. It is commonly found in baked goods, dried fruits, wines, and some processed vegetable products.

Sodium metabisulfite is an FDA-approved food additive. At typical intake levels, it is generally recognized as safe for most people. However, it can cause allergic-type reactions, including asthma symptoms, in some sulfite-sensitive individuals. JECFA has evaluated sodium metabisulfite and set an acceptable daily intake.