A sequestrant is a food additive which improves the quality and stability of foods. A sequestrant forms chelate complexes with polyvalent metal ions, especially copper, iron and nickel. This can prevent the oxidation of the fats in the food. Sequestrants are therefore a type of preservative.
The name comes from Latin and means "to withdraw from use".
Common sequestrants are: Calcium chloride (E509) Calcium acetate (E263) Calcium disodium ethylene diamine tetra-acetate (E385) Glucono delta-lactone (E575) Sodium gluconate (E576) Potassium gluconate (E577) Sodium tripolyphosphate (E451) Sodium hexametaphosphate (E452i)
Sodium and calcium salts of EDTA are also commonly used in many foods and beverages.
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