The use of polyphosphates to sequester or chemically lock-up the lime and magnesium in hard water, thus preventing the formation of film on parts or scale in machines.
A sequestrant is a food additive whose role is to improve the quality and stability of the food products. Sequestrants form chelate complexes with polyvalent metal ions. Especially copper, iron and nickel serve as catalysts in oxidation of the fats in the food.
An ingredient that releases itself or other ingredients slowly into a product over a period of time. Usually refers to preservatives, which have a "time-release" action in maintaining the color, consistency, and fragrance of a product.