FCC4, BP2000, USP, Food Additives Potassium Sorbate is one of the best preservatives ... : white granular or powder 2) Standard: conform to FCCIV, BP2000, USP, E202 3) Assay (C6H7KO2): 98.0-101.0% 4) Acidity ... .0% max. 5) Alkalinity: 0.28-1.0% max. 6) Loss on drying: 1.0% max. 7) Aldehydes (as formaldehyde): 0.1% max ...