The effects of a pickling process on the reduction of escherichia coliO157: H7, listeria monocytogenes, salmonella spp. and staphylococcus aureus inoculated onto hard-cooked eggs

Traditional methods of food preservation, such as pickling, have reemerged as popular approaches for home and commercial food processing. The process of pickling hard-cooked eggs (HCE) can be an effective method of preventing the growth and survival of pathogenic microorganisms. Because of the variety of pickling processes, HCE manufacturers must validate their pickling process for Food and Drug Administration (FDA) approval and demonstrate 5-log reductions of pathogens associated with the product. In this study, a rapid one-step pickling process was evaluated for its ability to reduce Salmonella spp., Listeria monocytogenes, Staphylococcus aureus and Escherichia coliO157:H7 inoculated onto HCE for 14days at room temperature. All pathogens inoculated onto HCE were reduced by (>5.0 logs) within 24h and were undetectable following enrichment. The data obtained in this study may be of interest to regulatory officials and processors of HCE seeking pathogen reduction validation for their products. Practical Applications: Pickling of HCE is an effective preservation method capable of preventing pathogen growth and survival. Although the use of organic acids for food preservation is not a new concept, few published studies have scientifically validated the ability of pickling methods to inhibit pathogen growth and survival on specific foods. Because of the regulatory requirements set forth by the FDA, acidified foods sold commercially must be validated through scientific studies, which demonstrate 5-log reductions of pathogens associated with the product. Previous studies have utilized a two-step pickled egg pickling process and demonstrated complete kill of various pathogens within 96h. In this study, we evaluate a rapid one-step pickling process utilizing a reformulated pickling solution and produce a complete kill of selected pathogens within 24h, drastically reducing the cost and increasing the efficiency of a commercial pickled egg pickling process.