Potassium metabisulfite is a potassium salt of sulphurous acid.
It appears, at room temperature, as a white, unstable powder, which forms potassium sulphate by reacting with oxygen.
In the presence of acids, it forms sulphurous acid.
Potassium metabisulfite is mainly used as a preservative, as well as a bleaching and oxidizing agent.
It can be contained in onion preserves, wine, fruit preserves, seafood etc.
It could reduce the vitamin content in various products.
It does not appear to have any negative side effects.
ADI DOSE: 0.7 mg per kg of body weight
