Potassium Benzoate Potassium Benzoate, or E212, is a colorless white crystalline powder that is used as a preservative in foods. It prevents bacteria and fungi from contaminating food, beverages, cosmetics, dental care products, and pharmaceuticals. Potassium Benzoate is an alternative to Sodium Benzoate when low sodium content is required. It is the potassium salt of benzoic acid and works best under acidic conditions. In presence of Vitamin C (ascorbic acid) such as in jams, sodium benzoate can form the chemical benzene. Benzene is known to damage DNA, genetic material, which can lead to leukemia and other cancers. Fruit juice, pickles, and soft drinks can be preserved with potassium benzoate. Most countries approve the use of potassium benzoate, but the European Union suggests children not to consume products preserved with it. Since sodium benzoate works best in acidic environments, the consumption of sodium benzoate is a rising issue. â€œPotassium Benzoate.â€� Tech-FAQ. Web. 17 May 2011.