Submitted to: Poultry Science
Publication Type: Abstract Only
Publication Acceptance Date: March 9, 2004
Publication Date: July 25, 2004
Citation: Berrang, M.E., Meinersmann, R.J., Smith, D.P., Frank, J.F. 2004. Listeria monocytogenes prevalence and distribution within a poultry further processing plant over 12 months [abstract]. Poultry Science. 83(suppl.1):11. Technical Abstract: In light of recent outbreaks and FSIS directives, it is important for poultry further processors to define the potential for cross contamination or cooked product re-contamination with Listeria monocytogenes. The objective of this study was to determine the prevalence of L. monocytogenes in a commercial poultry further processing plant. Furthermore, the effect of production shift activities on the spread of the organism was examined. One line producing fully cooked product was sampled 9 times over the course of a year (approximately every 6 weeks). Environmental sites were sampled by sponge or swab between sanitation and start up of production (pre-op) and again after an entire 8 hour shift was completed (post-op). Sample sites on both the raw and cooked side of the line included drain pipes, drain covers and condensate drip tubes from overhead coolers. Further pre-op and post-op sampling was conducted on cooked product contact surfaces. During the course of the production shift, purge from each bin of raw meat used for product formulation was collected and variable additional samples (16 per sample day) were collected in an effort to 'hunt' for the organism. All samples were cultured using the FSIS L. monocytogenes protocol of preenrichment in Listeria enrichment broth and selective enrichment in Fraser broth. Darkened Fraser broth was plated on modified oxford agar and any presumptive Listeria isolates were confirmed as L. monocytogenes using the FSIS cultural confirmation protocol. In 7 of 9 samplings at least one drain on the raw side was positive before production began. Raw side drains were positive at post-op in 8 of 9 trips. L. monocytogenes was never detected in cooked side drains or on product contact surfaces at pre-op; however, in 5 of 9 samplings one floor drain was positive at post-op. Despite such drain contamination, L. monocytogenes was not detected on any cooked product contact surface. L. monocytogenes was detected in raw meat used for product formulation in 8 of 9 samplings suggesting a possible source of plant contamination.