Potassium Benzoate
The short version
The potassium salt of benzoic acid — a sodium-free alternative to E211 in acidic foods.
It's permitted and generally considered safe, but there are a few reasons to be mindful — like sensitivities in some people, debated studies, or intake limits. The Safety section below explains the specifics.
Where it comes from
Produced by neutralizing benzoic acid (E210) with potassium hydroxide. Adopted as a sodium-restricted alternative in beverages, pickles, and dressings where sodium budgets matter (cardiovascular formulations).
How it's used
Used at 0.05% to 0.1% in acidic foods — soft drinks, fruit-flavored beverages, salad dressings, and pickles. Functionally interchangeable with sodium benzoate (E211): the antimicrobial actor is the undissociated benzoic acid that forms at pH below 4.5.
Safety profile
ADI of 0–5 mg/kg body weight (as benzoic acid, combined with E210/E211/E213). Same concerns and interactions as sodium benzoate: can form benzene with ascorbic acid (E300) under heat and light, especially with copper or iron catalysts. Linked to behavioral effects in the Southampton trial when combined with synthetic dyes.
Physical & chemical properties
White crystalline powder, very soluble in water (more so than sodium benzoate). Best activity at pH < 4.5. Stable in storage; loses preservation efficacy above pH 6.
Regulation worldwide
Permitted globally with the same maximum levels as other benzoates (typically 150–1500 mg/kg depending on food category).
Educational information only. Not medical or dietary advice.