The potassium salt of benzoic acid (E210).

Used as a preservative, both antibacterial and antifungal.

Can be found in margarine, pickled cucumbers, pineapple juice and table olives.

People who suffer from asthma, aspirin sensitivity or the skin disease urticaria may have allergic reactions and/or find their symptoms become worse following consumption of benzoic acid, particularly in combination with tartrazine (E102).

Not recommended for consumption by children.