Triphosphates E451
sequestrant, stabilizer, moisture retention agent — Primarily synthetic.
Pentasodium triphosphate (E451i), Pentapotassium triphosphate (E451ii)
CAS: 7758-29-4 (i), 13573-18-7 (ii)
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
What Is Triphosphates?
Triphosphates (pentaphosphates: pentasodium triphosphate and pentapotassium triphosphate) function as sequestrants, emulsifying salts, and water-binding agents in processed meats, seafood, poultry, and processed cheeses. They chelate metal ions (preventing oxidative rancidity), improve water retention in injected meat products, and stabilize protein emulsions in processed cheese. JECFA's group ADI of 70 mg/kg body weight (as phosphorus) covers all phosphate additives. EFSA reviewed phosphates in 2019. Triphosphates are globally approved and widely used in the seafood and meat processing industries.
? Did You Know?
Beyond food, Triphosphates is also used in cosmetics, medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.
Regulatory Analysis
Triphosphates (tripolyphosphates, E451) share the phosphate additive group ADI revised by EFSA in 2019, but carry an additional layer of regulatory controversy specific to the seafood industry. Sodium tripolyphosphate (STPP) is widely used to treat frozen shrimp and scallops, where it significantly increases product weight through water retention — a practice that has attracted food fraud enforcement attention in multiple markets, as mislabeled water content inflates apparent product weight and price. This application falls outside the scope of EFSA's food additive assessment (which concerns toxicological acceptability, not commercial transparency) but has resulted in labeling requirements in the EU and some other jurisdictions mandating disclosure of added water in STPP-treated seafood. The toxicological basis for E451 remains the group phosphate ADI of 40 mg/kg body weight per day (EFSA 2019), identical to other phosphate additives.
Detailed Regulatory Assessment
European Union (EFSA)
Quantum satis in many categories; specific limits apply due to concerns about total dietary phosphate intake.
Official EFSA LinkUnited States (FDA)
Widely used in seafood processing
Japan (MHLW)
Compliant with Japanese food sanitation law.
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Natural Occurrence
This additive is not known to occur naturally in significant quantities.
Manufacturing
Produced by heating a mixture of monosodium phosphate and disodium phosphate to approximately 540-560°C, causing condensation to form sodium triphosphate. The process involves controlled dehydration and polymerization of orthophosphates.
Applications Beyond Food
Chelating agent and pH adjuster in personal care products.
Excipient in pharmaceutical formulations.
Heavy-duty detergents, water softening, ceramic production, paper processing, petroleum refining.
Laundry detergents (historically common, now restricted in many regions due to environmental concerns about phosphates in wastewater).