Preservative: Potassium Metabisulfite

Potassium metabisulfite is a white or slightly yellowish crystalline powder. It is a salt of sulfurous acid, produced industrially by treating potassium carbonate or potassium hydroxide with sulfur dioxide. It is often used as a preservative and antioxidant.

Potassium metabisulfite is added to foods and beverages to prevent spoilage by inhibiting the growth of bacteria and molds. It also acts as an antioxidant, preventing browning in fruits and vegetables and preserving the color and flavor of processed foods. It is commonly found in dried fruits, wine, fruit juices, and processed potatoes.

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, leading to symptoms like hives, wheezing, or digestive upset. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has evaluated potassium metabisulfite and established an acceptable daily intake. Evidence regarding its long-term health effects at typical consumption levels is mixed, with some studies suggesting potential benefits and others raising concerns.