What is E451?

Sodium triphosphate (STP), also sodium tripolyphosphate (STPP), or tripolyphosphate (TPP),) 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. E451 sits in the E400–E499 series, which in the EU classification mainly covers thickeners, stabilisers and emulsifiers.

What is E451 used for?

E451 belongs to the emulsifiers group. Emulsifiers help water and fat mix, found in everything from chocolate to bread. Most are considered safe.

Is E451 safe?

E451 is rated “moderate”. It is approved for use in food, but some people prefer to limit it. “Moderate” means it is approved, but is debated or something some people prefer to limit.

How E451 appears on labels

On food packaging you'll find E451 either as the number “E451” or by the name “Triphosphates” in the ingredient list, often after its function. Ingredients are listed in descending order by weight, so an additive near the end is present only in small amounts.

Is E451 vegan?

Yes, E451 is suitable for vegans.