Sodium Metabisulfite, also called Sodium Pyrosulfite or Disodium, is an inorganic compound composed of sodium, sulfur and oxygen. Its chemical formula is Na2S2O5. It typically comes in a white or yellowish-white crystalline powder. It easily dissolves in water. The substance is sometimes referred to as disodium (metabisulfite). It is used as a disinfectant,antioxidant and preservative agent.
Many chemical properties of sodium metabisulfite or sodium pyrosulfite make it a versatile compound useful in many applications. It can eliminate dissolved oxygen in waste water and in pipes. It functions as a bleaching agent, which is useful in making paper pulp, cotton and wool. It is used in water treatment plants to remove excess chlorine. In beer and wine manufacturing, sodium metabisulfite or sodium pyrosulfite checmicals are often used to sterilize the equipment.
Sodium metabisulfite or sodium pyrosulfite is used as a food preservative. It is commonly used as a food preservative for dried foods, like potato chips, raisins and apples, as well as fruit concentrate juices. It acts as an antimicrobial, inhibiting the growth of fungi and bacteria, thereby keeping food fresh and safe.
Sodium metabisulfite is an antioxidant additive in injectable medicines and is also used as a reducing agent in pharmaceuticals.