In food, sodium metabisulfite is usually used as food preservative

 As a cleaner, the compound is also present in wine and beer because it is used as a bactericide and antioxidant in the brewing or fermentation of beer. If you or someone you know claims to be allergic to red wine, it may be because of the presence of sodium metabisulfite.

 As an antibacterial agent, the chemical is also used for water purification, cleaning water pipe and reverse osmosis membrane in desalination equipment.

 In addition, its acidity and corrosion resistance make it an effective substitute for sodium bisulfite, which is a chemical used in traditional darkroom photography.

In addition, sodium metabisulfite is also used as a bleaching agent in the manufacture of pulp and textiles, and as a reducing agent in medicine. It is also a preservative in cosmetics.