STPP is a preservative for seafood, meats, poultry, and animal feeds. It is common in food production as E number E451. In foods, STPP is used as an emulsifier and to retain moisture. Many governments regulate the quantities allowed in foods, as it can substantially increase the sale weight of seafood in particular.
Sodium Tripolyphosphate, is used as a preservative for poultry, meat, and seafood. It is also added, along with other sodium polyphosphates, to processed cheeses as an emulsifier. The polyphosphates are negatively charged chains of phosphorus and oxygen that attract water molecules.