Potassium benzoate is the potassium salt of benzoic acid, is a food preservative that inhibits the growth of mold, yeast and some bacteria. Acidic foods and beverages such as fruit juice, sparkling drinks, soft drinks and pickles may be preserved with potassium benzoate. It is approved for use in most countries including Canada, the USA., and the EU, where it is designated by the E number E212.
C7H5KO2 160.21
Benzoic acid, potassium salt.
Potassium benzoate [582-25-2].
Potassium Benzoate contains not less than 99.0 percent and not more than 100.5 percent of C7H5KO2, calculated on the anhydrous basis.
Identification: It responds to the flame test for Potassium and to the tests for Benzoate.
Alkalinity: Dissolve 2 g in 20 mL of hot water, and add 2 drops of PhPh: the pink color produced, if any, is discharged by the addition of 0.20 mL of 0.10 N sulfuric acid.
Water: not more than 1.5%.
Heavy metals: the limit is 0.001%.
Assay: Transfer about 600 mg of Potassium Benzoate, accurately weighed, to a 250-mL beaker. Add 100 mL of glacial acetic acid, stir until the assay specimen is completely dissolved, add 2 drops of crystal violet and titrate with 0.1 N perchloric acid. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 16.02 mg of C7H5KO2.
C7H5KO2 Formula wt 160.22
INS: 212 CAS: [582-25-2]
DESCRIPTION
Potassium Benzoate occurs as white granules, crystalline powder, or flakes. One gram dissolves in 2 mL of water, in 75 mL of alcohol, and in 50 mL of 90% alcohol.
Function: Preservative; antimicrobial agent.
REQUIREMENTS
Identification: A 1:5 aqueous solution responds to the flame test for Potassium and gives positive tests for Benzoate.
Assay: Not less than 99.0% and not more than 100.5% of C7H5KO2, calculated on the anhydrous basis.
Alkalinity: (as KOH) Not more than 0.06%.
Lead: Not more than 2 mg/kg.
Water: Not more than 1.5%.
