Potassium hydroxide
Completely safe when used as an acidity regulator.
- Category
- Acidity regulators
- Vegan
- Yes
- Vegetarian
- Yes
What it is
An inorganic compound used as an acidity regulator and color stabilizer.
How it is used in food
A strong alkali used in tiny amounts as an acidity regulator, and in processes such as alkalising cocoa, where it neutralises acids and darkens colour and mellows flavour.
Commonly found in- Cocoa products
- Baked goods
- Peeling of fruits and vegetables
Health and safety
A safe, common food processing aid that breaks down into dietary potassium and water.
EFSA's evaluations of food hydroxides found no safety concern: in food, potassium hydroxide is immediately neutralised, dissociating into potassium ions (a normal nutrient) and water. It carries no residual alkalinity by the time the product is eaten.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| Australia & New Zealand FSANZ |
Permitted | Permitted under the FSANZ Food Standards Code. |
| European Union EFSA / European Commission |
Permitted | Authorised for food use under EU regulations (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
- E525
Worth knowing
Also called caustic potash, it was historically made by leaching wood ashes — the origin of the word 'potash' and ultimately of the element name potassium itself.
Conclusion
Completely safe when used as an acidity regulator.
References
Is it in what you are buying?
ScanWise reads the barcode and tells you which additives a product actually contains, and what they do to its score.
Open the appEntry last reviewed 2026-07-28.
← All additives