Description
Sodium triphosphate (STP), also sodium tripolyphosphate (STPP) is
an inorganic compound with formula Na5P3O10. It is the sodium salt
of the polyphosphate penta-anion, which is the conjugate base of
triphosphoric acid. It is produced on a large scale as a component
of many domestic and industrial products, especially
detergents.
STPP 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.
Other uses include ceramics (decrease the viscosity of glazes up to
a certain limit), leather tanning (as masking agent and synthetic
tanning agent SYNTAN), anticaking, setting retarders, flame
retardants, paper, anticorrosion pigments, textiles, rubber
manufacture, fermentation, antifreeze.