E339: Trisodium phosphate

What is E339?

E339iii is trisodium phosphate, a fully neutralised sodium salt of phosphoric acid. It is a white, strongly alkaline powder that dissolves readily in water.

Origin and production

Trisodium phosphate is made by neutralising purified phosphoric acid, derived from phosphate rock, with sodium hydroxide or sodium carbonate. It is mineral in origin.

Why is it used?

Thanks to its alkalinity, it is used as an acidity regulator, emulsifying salt and sequestrant; in breakfast cereals it helps adjust pH, improving colour and flow during extrusion. It appears in breakfast and extruded cereals, snacks, some pizzas and certain beverages.

Vegan, vegetarian and halal

E339iii is a mineral salt, suitable for vegans and vegetarians. It raises no particular halal or kosher concerns.

Safety and regulation

Trisodium phosphate is authorised as a food additive in the European Union and was included in EFSA's 2019 re-evaluation of phosphates, which set a group acceptable daily intake for phosphorus from phosphate additives. It is also permitted in many other countries.

Common in