Calcium Propionate (E282) is produced commercially by neutralizing propionic acid with calcium hydroxide or calcium carbonate. In its natural production variant, the propionic acid precursor is obtained via fermentation using Propionibacterium freudenreichii or Propionibacterium acidipropionici, the same organisms responsible for propionate production in Swiss-type cheese.
This fermentation-derived propionic acid is then neutralized to form calcium propionate that can be labeled as 'natural' in appropriate markets. Propionate functions as an antimicrobial by inhibiting spore germination and vegetative cell growth of molds and rope-forming bacteria, primarily by interfering with CoA-dependent metabolic pathways. JECFA established an ADI of 'not limited' for propionic acid and propionates; it is approved globally including EU, FDA (21 CFR 184.1221), and Codex Alimentarius.