ARS | Publication request: REDUCING MICROBIAL CONTAMINATION DURING SHELL EGG PROCESSING

Submitted to: Midwest Poultry Federation Proceedings
Publication Type: Proceedings
Publication Acceptance Date: March 1, 2006
Publication Date: March 15, 2006
Citation: Musgrove, M.T., Jones, D.R., Northcutt, J.K., Cox Jr, N.A., Harrison, M.A. Reducing microbial contamination during shell egg processing. Midwest Poultry Federation Proceedings, March 21-23, 2006, St. Paul, Minnesota. CDROM

Technical Abstract: Over the years, egg shell microbiology has been studied extensively but little of it describes how modern US processing conditions impact bacterial populations. As safety-based regulations are being drafted for the industry, this information can be important in determining processing steps that are critical to product safety. Five different shell egg surface populations (aerobic, yeasts/molds, Enterobacteriaceae, E. coli, and Salmonella spp.) were monitored at twelve points along the processing line (accumulator, pre-wash rinse, washer one, washer two, sanitizer, dryer, oiler, scales, two packer head lanes). Three commercial facilities were visited three times resulting in 990 eggs and 5,220 microbiological analyses. Though variations existed in levels recovered from plant to plant the patterns of fluctuations for each population were similar at each plant. On average, aerobes, yeasts/molds, Enterobacteriaceae, and E. coli populations were reduced by 30%, 20%, 50% and 30%, respectively by processing. Log10 CFU / ml rinse on eggs collected from packer head lanes were decreased by 3.3, 1.3, 1.3, and 0.5, respectively, when compared to rinses from eggs collected at the accumulator. Salmonella were recovered from 0 – 48 % of pooled samples in the six repetitions. More Salmonella were recovered from pre-processed than in-process or ready to pack eggs. These data demonstrate that current commercial practices decrease microbial contamination of egg shell surfaces.