E340III - Tripotassium phosphate

At a glance

• What it is: the tribasic potassium salt of phosphoric acid, known as E340iii.
• What it does: works as an acidity regulator (buffer), emulsifier, stabiliser, thickener, and sequestrant.
• Where it’s used: processed cheese, dairy and dairy-alternative drinks, powdered mixes, cured meats, and baked goods.
• Nutrition note: contributes small amounts of potassium and phosphorus.
• Safety: approved in the EU within set rules; EFSA set a group acceptable daily intake (ADI) for all phosphate additives. People with kidney problems may need to limit phosphate and potassium additives.

Why is Tripotassium phosphate added to food?

Manufacturers use tripotassium phosphate to keep acidity in balance, help proteins and fats mix smoothly, and prevent minerals from causing off-textures. In processed cheese, for example, it helps the cheese melt evenly and stay creamy. In drinks and powders, it stabilises the mixture and binds metal ions so they don’t cause haze or off-flavours.¹

What foods contain Tripotassium phosphate?

Tripotassium phosphate is authorised in the EU across a wide range of categories. You may see it in processed cheeses, dairy and plant-based beverages, meat and poultry products, bakery items, and powdered drink mixes and creamers.¹

On labels it can appear as “tripotassium phosphate,” “tribasic potassium phosphate,” or “E340iii.”

What can replace Tripotassium phosphate?

Depending on the job it’s doing, formulators might switch to:

• Other potassium phosphates: monopotassium phosphate or dipotassium phosphate.
• Sodium-based buffers and emulsifying salts: sodium phosphates or sodium citrates.
• Acidulants and chelators: citric acid or phosphoric acid.
• Texture agents: xanthan gum, carrageenan, or guar gum.
• For baking systems: sodium carbonates and monocalcium phosphate.

How is Tripotassium phosphate made?

Food-grade tripotassium phosphate is typically produced by fully neutralising purified phosphoric acid with potassium hydroxide or potassium carbonate, then drying and milling the crystals. The reaction converts the acid to the tribasic salt (K3PO4) with water or carbon dioxide as by-products.² Its identity as K3PO4, a strong alkaline salt, is well established in chemical references.³

Is Tripotassium phosphate safe to eat?

In the European Union, phosphate additives (including E340iii) are authorised and must meet purity specifications. The European Food Safety Authority (EFSA) set a group acceptable daily intake (ADI) for phosphates of 40 mg per kg body weight per day, expressed as phosphorus, covering combined exposure from all phosphate additives.⁴ For most people eating a varied diet, typical exposures are below this level, especially when additives are used within legal limits and good manufacturing practice.¹

Does Tripotassium phosphate have any benefits?

• Technical: It keeps foods stable, smooth, and evenly melted or mixed, which improves quality and shelf life.¹
• Nutritional: It supplies potassium and phosphorus ions. While this can contribute to electrolyte balance and mineral intake, the amounts in a single serving are usually modest.

Who should avoid Tripotassium phosphate?

• People with chronic kidney disease or those advised to limit phosphorus: Added phosphates are readily absorbed and can raise blood phosphorus; medical guidelines often recommend limiting phosphate additives.⁵
• People who must restrict potassium (for example, some kidney patients or those at risk of high blood potassium): Potassium salts, including tripotassium phosphate, add dietary potassium.⁶
• High consumers in young age groups: EFSA noted that in some children with high intakes, total exposure to phosphate additives could exceed the group ADI; families can manage this by checking labels and varying foods.⁴

If any of these apply to you, ask a healthcare professional or dietitian for personalised advice.

Myths & facts

• “It’s only a cleaning chemical.” Food-grade tripotassium phosphate is highly purified and must meet strict specifications before use in foods.²
• “All phosphates are the same.” Different phosphate salts (potassium, sodium, calcium) behave differently in recipes; they’re chosen for specific functions.¹
• “It’s unsafe.” Regulators allow it within set uses and limits. EFSA has evaluated phosphate additives as a group and set an ADI to guide safe intake.⁴
• “It always causes high phosphorus.” Most people won’t exceed the ADI with a balanced diet, but those with kidney disease may need to limit added phosphates.⁵

Tripotassium phosphate in branded foods

You’ll most often spot it on ingredient lists for processed cheese, shelf-stable creamers and drink powders, meat and poultry products, breakfast cereals, and ready-to-drink beverages. It may appear as “tripotassium phosphate,” “tribasic potassium phosphate,” or simply “E340iii.” If you prefer to limit phosphate or potassium additives, compare labels across similar products and choose options that use alternatives like sodium citrates or citric acid instead.

References

Footnotes

1. Regulation (EC) No 1333/2008 on food additives — Definitions, authorisations and use conditions. https://eur-lex.europa.eu/eli/reg/2008/1333/oj ↩ ↩² ↩³ ↩⁴ ↩⁵

2. Commission Regulation (EU) No 231/2012 — Specifications for food additives (E340 potassium phosphates). https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩²

3. Tripotassium phosphate — PubChem, NIH. https://pubchem.ncbi.nlm.nih.gov/compound/Tripotassium-phosphate ↩

4. Re-evaluation of phosphoric acid–phosphates–di-, tri- and polyphosphates (E 338–341, E 343, E 450–452) as food additives — EFSA Journal. https://www.efsa.europa.eu/en/efsajournal/pub/5674 ↩ ↩² ↩³

5. Phosphorus — Office of Dietary Supplements, NIH. https://ods.od.nih.gov/factsheets/Phosphorus-Consumer/ ↩ ↩²

6. Potassium — Office of Dietary Supplements, NIH. https://ods.od.nih.gov/factsheets/Potassium-Consumer/ ↩