Inactivation of Salmonella enteritidis on shell eggs by novel N-halamine biocidal compounds

Abstract

Several new N-halamine compounds have been evaluated as potential replacements for free chlorine as disinfectants for the egg-processing industry. The compounds were tested against Salmonella enteritidis on the surfaces of egg shells. Test procedure included spraying inoculated egg shells with solutions of several of the N-halamine compounds and free chlorine for comparison, suspending the most stable N-halamine compound in a thin coating of mineral oil on the egg shell and subsequent inoculation, and measuring the rates of diffusion of the compounds and free chlorine through the egg shells. Compounds DBC (1-bromo-3-chloro-2,2,5,5-tetramethylimidazolidin-4-one) and DC (1,3-dichloro-2,2,5,5,-tetramethylimidazolidin-4-one) were significantly more efficacious than free chlorine in inactivating Salmonella in the spray experiments, while compound MC (1-chloro-2,2,5,5-tetramethylmidazolidin-4-one), in a mineral oil suspension, provided disinfection of the egg shells within 72 h of contact. None of the disinfectant compounds penetrated egg shells at a rate greater than 1 mg/l over a period of 6 h. Compound MC is recommended as a possible replacement for unstable, corrosive-free chlorine as a bactericide for the egg-processing industry. © 1992 Society for Industrial Microbiology.