E340 - Potassium phosphates

At a glance

• What it is: A group of salts of phosphoric acid with potassium. E340 covers three forms: E340(i) monopotassium phosphate, E340(ii) dipotassium phosphate, and E340(iii) tripotassium phosphate.
• What it does: Regulates acidity (buffer), stabilizes proteins, helps emulsify fat and water, binds metal ions (sequestrant), and can thicken.
• Where it’s used: Soft drinks and sports drinks, plant-based milks and creamers, processed cheeses, cured or injected meats, bakery mixes, and instant beverages.
• Label names: “Potassium phosphates,” “monopotassium phosphate,” “dipotassium phosphate,” “tripotassium phosphate,” or “E340.”
• Dietary notes: Vegan-friendly and gluten-free. Adds potassium and phosphorus to the diet.

Why is Potassium phosphates added to food?

Potassium phosphates keep foods stable and consistent. As acidity regulators and buffers, they hold pH in the right range so flavors stay balanced and proteins don’t curdle. As stabilizers and emulsifiers, they help oil and water stay mixed, which is useful in products like creamers and processed cheese. They also bind trace metals (as sequestrants), helping protect color and flavor during shelf life. Because they contribute potassium instead of sodium, manufacturers sometimes choose them over sodium versions to help reduce sodium in recipes.

What foods contain Potassium phosphates?

You’ll commonly find E340 in:

• Drinks: powdered and ready-to-drink sports beverages, flavored waters, energy drinks, and some sodas
• Dairy and alternatives: nondairy creamers, plant-based milks, processed cheeses, and cheese spreads
• Meat and seafood: brines, injected or tumbled meats, and some seafood treatments
• Bakery and mixes: cake, pancake, and dessert mixes, cocoa mixes, and instant beverages
• Other: powdered soups and sauces, instant noodles, and meal replacements

In the European Union, E340 is permitted in many food categories with specific maximum levels set in Annex II of the food additives regulation.¹

What can replace Potassium phosphates?

Alternatives depend on the job you need done:

• For acidity control and buffering: sodium phosphates, calcium phosphates, sodium citrates, or citric acid
• For emulsifying and stabilizing proteins: polyphosphates, diphosphates, or phosphoric acid in combination with other salts
• For leavening systems or pH adjustments in baking: potassium carbonates

How is Potassium phosphates made?

Food-grade potassium phosphates are produced by neutralizing purified phosphoric acid with potassium bases such as potassium hydroxide or potassium carbonate. Adjusting the ratio during neutralization yields the three common salts: monopotassium phosphate (KH2PO4), dipotassium phosphate (K2HPO4), or tripotassium phosphate (K3PO4). After reaction, the product is filtered and crystallized to meet food specifications.²

Is Potassium phosphates safe to eat?

Yes—when used as intended. In 2019, the European Food Safety Authority (EFSA) set a group acceptable daily intake (ADI) for phosphates of 40 mg per kilogram of body weight per day, expressed as phosphorus (P), covering E338–E341, E343, and E450–E452, which includes potassium phosphates.³ In the United States, monopotassium phosphate and dipotassium phosphate are listed by the Food and Drug Administration (FDA) as generally recognized as safe (GRAS) when used in line with good manufacturing practice.⁴⁵ In the EU, use is limited by food-by-food maximum levels to help control total exposure.¹

Does Potassium phosphates have any benefits?

From a food-making point of view, potassium phosphates bring several advantages:

• Keep proteins stable in heat-treated or acidic products, improving texture and preventing curdling
• Support smooth mixing of fat and water in creamers and processed cheese
• Maintain flavor by holding pH steady and binding trace metals that can cause off-notes
• Provide potassium while helping reduce sodium when used instead of sodium salts

Who should avoid Potassium phosphates?

People who are advised to limit phosphorus—especially those with chronic kidney disease (CKD)—should watch for phosphate additives, including E340, because they add readily absorbed phosphorus to the diet.⁶ If you’re on a potassium-restricted diet or taking medicines that affect potassium levels, ask your healthcare provider about whether potassium-containing additives fit your plan.

Myths & facts

• Myth: “All phosphates are the same.” Fact: E340 covers three different potassium salts with slightly different strengths and uses in food.
• Myth: “Phosphate additives are only preservatives.” Fact: Their main roles are buffering, stabilizing proteins, and helping emulsify ingredients.
• Myth: “If a product is ‘dairy-free,’ it won’t have phosphates.” Fact: Many dairy alternatives and creamers use dipotassium phosphate to keep proteins stable and prevent separation.
• Myth: “Phosphates are unsafe.” Fact: Regulators permit them with limits, and EFSA has set an ADI to manage overall exposure.³

Potassium phosphates in branded foods

You may see potassium phosphates on ingredient lists for:

• Nondairy creamers and shelf-stable coffee drinks (often “dipotassium phosphate”)
• Processed cheese slices and spreads
• Sports drinks and electrolyte powders (often “monopotassium phosphate”)
• Injected or marinated meats and some seafood
• Instant cocoa, soups, and gravy or sauce mixes

On labels, look for “E340,” “monopotassium phosphate,” “dipotassium phosphate,” or “tripotassium phosphate.”

References

Footnotes

1. Regulation (EC) No 1333/2008 on food additives (Annex II) — EUR-Lex. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32008R1333 ↩ ↩²

2. Monopotassium phosphate — PubChem (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/516951 ↩

3. EFSA sets limit for phosphates added to food — European Food Safety Authority. https://www.efsa.europa.eu/en/news/food-additives-phosphates ↩ ↩²

4. 21 CFR 182.6285 Monopotassium phosphate — U.S. FDA eCFR. https://www.ecfr.gov/current/title-21/section-182.6285 ↩

5. 21 CFR 182.6287 Dipotassium phosphate — U.S. FDA eCFR. https://www.ecfr.gov/current/title-21/section-182.6287 ↩

6. Phosphorus in diet — MedlinePlus (NIH). https://medlineplus.gov/ency/article/002424.htm ↩