Sodium Tripolyphosphate’s Application

Sodium tripolyphosphate (STPP), also known as sodium triphosphate, is the sodium salt of triphosphoric acid.  STPP is a colorless salt that exists both in anhydrous form Na5P3O10 and in hexahydrate form H12Na5O16P3.  It is frequently used as a food preservative and as a water softener in commercial detergents.

As a food additive STPP helps with moisture retention and is used to preserve the natural color of meat and fish products while improving their texture.  It acts as an emulsifier and helps to prevent meat, poultry, or fish from becoming greasy and falling apart during heating.  STPP is commonly used in meat and dairy processing.

In cleaning products, STPP improves the ability of detergents to penetrate fibers and other materials.  It also aids in foaming, and its pH buffering ability makes it useful as a water softener.  Many household cleaning products such as kitchen and bathroom cleaners contain STPP.

STPP has numerous other industrial uses including:

Sequestrant for alkaline metals

Pulp and paper production: anti-“pitch” agent for raw pulp

Tartar control agent

Corrosion control

Lead control

Leather tanning agent

Whitening agent