Potassium fumarate
Not authorised in EU, but permitted in AU-NZ and US. No evidence of harm at dietary intake.
- Category
- Acidity regulators
- Vegan
- Yes
- Vegetarian
- Yes
What it is
A potassium salt of fumaric acid, used as a buffer and acidity regulator.
How it is used in food
Potassium fumarate delivers fumaric acid's strong, persistent sourness in a freely soluble, sodium-free form, which makes it particularly useful in reduced-sodium formulations. It buffers pH in beverages, gelatine desserts and bakery fillings and contributes potassium, a mineral most diets under-supply relative to sodium.
Commonly found in- Historically in food processing
Health and safety
Not explicitly authorised in the EU.
JECFA's ADI of 6 mg/kg body weight per day for fumaric acid and its salts, expressed as fumaric acid, covers this compound. Only fumaric acid (E 297) is authorised in the EU; the potassium salt is permitted in the United States and Australia–New Zealand. Potassium load is worth noting for people with advanced kidney disease, though additive-level intakes are small.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| Australia & New Zealand FSANZ |
Permitted | Permitted under the FSANZ Food Standards Code. |
| European Union EFSA / European Commission |
Not approved | Not on the EU authorised list of food additives (Annex II). |
| United States FDA (Food and Drug Administration) |
Permitted | Authorised for food use by the FDA (often GRAS for standard additives). |
Identification on labels
- E-number
- E366
Worth knowing
Substituting the potassium salt for the sodium one is a quiet reformulation trick: it shifts a product's sodium-to-potassium ratio in the direction dietary guidelines recommend without changing the taste profile at all.
Conclusion
An unauthorized synthetic buffering agent.
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Open the appEntry last reviewed 2026-07-28.
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