ARS | Publication request: Scald tank water and foam as sources of carcass contamination during early poultry processing

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 26, 2009
Publication Date: January 26, 2009
Citation: Liljebjelke, K.A., Ingram, K.D., Hinton Jr, A., Cason Jr, J.A. 2009. Scald tank water and foam as sources of carcass contamination during early poultry processing [abstract]. Meeting Abstract. January 26-27, 2009. p. 28.

Technical Abstract: Salmonella remains a leading cause of bacterial foodborne illness in the United States, with poultry consumption associated with forty percent of outbreaks for which vehicles are identified. Identifying sources of Salmonella contamination and cross-contamination within poultry processing is imperative to developing effective control programs. We enumerated Enterobacteriaceae, coliforms, and Escherichia coli, and isolated Salmonella from scald tank water, scald tank foam, and defeathered carcasses obtained from a commercial poultry processing plant during the second processing shift for nine consecutive weeks. Using Biolog GM metabolic fingerprinting, we identified Enterbacteriaceae from these samples to species. Sixty percent of isolates were identified as E. coli, with Vibrio sp., Escherichia sp., Salmonella sp., Aeromonas sp., Enterobacter sp., and Raoutella sp. making up the majority of other Enterobacteria identified. Salmonella serotypes were isolated from carcass rinsate, water, and foam samples. The total Enterobacteria count from carcass rinsates (N=102) was mean log 3.7 cfu/ml. Total Enterobacteria counts from scald tank water decreased significantly (P<0.05) from the first tank to the third (mean log cfu/ml: 3.4, 2.5, 1.7). Enterobacteria counts from foam samples did not decrease significantly from tank-to-tank (LS mean log cfu/ml: 2.6, 2.2, 2.1), but contained significantly (P<0.05) fewer cfu than equal volumes of water from the same tanks. Despite high temperatures in the scald tanks (mean 50–53 0C), Enterobacteria survive in the water and in lesser amounts in surface foam. The organic foam layer that builds up on the scald tanks during processing may serve as a source of bacterial contamination during the early steps of poultry processing when carcasses pass through the foam.