Sodium Tripolyphosphate — STPP

Sodium Tripolyphosphate (STPP) is also known as pentasodium phosphate, sodium pyrophosphate, or sodium triphosphate. The appearance shape of sodium tripolyphosphate is white shiny particulate powder, which is usually packed with polyethylene plastic bags. Food grade sodium tripolyphosphate is widely used in food processing and is one of the food additives.
Sodium Tripolyphosphate


  • IUPAC name:   Pentasodium triphosphate
  • Other names: polygon, STPP
  • Chemical Formula: Na5P3O10
  • CAS Number: 7758-29-4
  • ECHA InfoCard 100.028.944

Technical Grade STPP

Technical grade STPP is mostly consumed as a component of commercial detergents. It serves as a “builder,” also act as a water softener in deterngent fomula. In some place, where water contains high concentrations of Mg2+ and Ca2+), so detergents are deactivated. Being a highly charged chelating agent, TPP5− binds to dications tightly and prevents them from interfering with the sulfonate detergent. 

Food Grade STPP

Food grade STPP can be used in canned or fruit juice drinks, vegetable protein drinks, dairy products, poultry products, meat products, ice cream, instant noodles, canned food, meat products, condensed milk; when sodium tripolyphosphate and sodium pyrophosphate, triphosphate When sodium is used in combination, it can also be used to make ham and smoked meat.
Food gradeSTPP is also used in the production of canned broad beans, which can soften the bean skin. Many fruits and vegetables have a tough outer skin. As the fruits and vegetables mature, the outer skin becomes tougher. Adding polyphosphate to fruit and vegetable processing blanching or soaking water can complex calcium, thereby reducing the toughness of the skin. For example, when pre-boiling broad beans, add appropriate amount of sodium tripolyphosphate and sodium hexametaphosphate, boil for 10 ~ 20min to soften the bean skin.
In general, food-grade STPP has great value in many foods as a water retention agent, quality improver, pH adjuster, and metal chelating agent.
Sodium Tripolyphosphate