ARS | Publication request: Low Levels of Bacteria Found on Rubber Picker Fingers During Processing

Submitted to: Poultry Science
Publication Acceptance Date: December 5, 2003
Publication Date: July 31, 2004
Citation: Arnold, J.W., Boothe, D.D. 2004. Low Levels Of Bacteria Found On Rubber Picker Fingers During Processing. [abstract] Poultry Science. 82(SUPPL.1).

Technical Abstract: For many years, the use of rubber fingers on mechanical pickers to remove feathers from broilers after scalding was considered a major contributor to bacterial cross-contamination. In previous work, bacterial attachment to picker-finger rubber was significantly less than attachment to stainless steel and other surface materials. In fact, new picker-finger rubber inhibited bacterial contamination. In this study, rubber picker fingers that had been in use in commercial processing equipment were tested with natural bacterial populations. Picker fingers were removed from various locations within an inline picker, bagged, and stored on ice for transport to the laboratory. The locations included front, center, and back to the right and left of the processing line. Three-rib sections cut from the middle of each finger were individually placed into 10 mL of tryptic soy broth. Serial dilutions for plate counts of colony forming units were performed after incubation at 37 C for one hour and vortexing. Three trials from each of three processing plants indicated that bacterial counts were much lower than expected, 30 to 104 per finger. Scanning electron microscopy confirmed the levels of surface bacteria. Fingers incubated for 72 to 96 hours and those exposed to bacterial cultures significantly increased and harbored bacterial levels to 105 and above. In one trial bacteria from the picker fingers were isolated and identified, but no pathogens were found. This indicates that picker fingers may not be a major source for pathogen cross contamination of carcasses. The minimal chemical control to completely eliminate bacterial contamination can now be determined. The results will impact the recommended schedule for replacing picker fingers.