Wiktionary
potassium benzoate
n. (context organic compound English) The potassium salt of benzoic acid.
Wikipedia
Potassium benzoate
Potassium benzoate (E212), the potassium salt of benzoic acid, is a food preservative that inhibits the growth of mold, yeast and some bacteria. It works best in low- pH products, below 4.5, where it exists as benzoic acid.
Acidic foods and beverages such as fruit juice ( citric acid), sparkling drinks ( carbonic acid), soft drinks ( phosphoric acid), and pickles ( vinegar) may be preserved with potassium benzoate. It is approved for use in most countries including Canada, the U.S., and the EU, where it is designated by the E number E212.
Potassium benzoate is also used in the whistle in many fireworks.