Antioxidant: Potassium Metabisulfite

Potassium metabisulfite is a white or slightly yellowish crystalline powder. It is a salt of sulfurous acid, made from potassium hydroxide and sulfur dioxide. It is used as a preservative and antioxidant.

Manufacturers add potassium metabisulfite to foods to prevent spoilage by inhibiting the growth of bacteria and molds. It also acts as an antioxidant, preventing browning and preserving color in foods like dried fruits, wine, and processed potatoes. It is commonly found in pickles, olives, and relishes.

Potassium 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. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has evaluated potassium metabisulfite and established acceptable daily intake levels. Evidence on its long-term health effects at typical consumption levels is mixed, with some studies suggesting potential impacts on gut health, while others find no significant adverse effects.