Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 28, 2008
Publication Date: February 25, 2009
Citation: Berrang, M.E., Bailey, J.S. 2009. On-line brush and spray washers to lower numbers of Campylobacter and E. coli and presence of Salmonella on broiler carcasses during processing. Journal of Applied Poultry Research. 18(1):74-78. Interpretive Summary: Campylobacter and Salmonella are human pathogens that can be found on poultry and poultry products. Broiler processing plants employ a wide range of physical and chemical techniques to lessen bacterial contamination. It is not known how different types of spray washers and brush washers impact bacterial numbers on broiler carcasses. Broiler carcasses were collected from a commercial processing plant directly before and after five separate on-line wash steps. Each carcass was examined for numbers of Campylobacter and E. coli and the presence of Salmonella. Overall, processing lessened bacterial contamination, carcasses had far fewer bacteria after all the wash steps were completed than before processing was started. Campylobacter numbers were lowered from 380 to 14 cells per mL of rinse; Salmonella prevalence decreased from 80% to 24%. However, when examined individually, no single wash step had a significant effect on the numbers of Campylobacter or the prevalence of Salmonella. Escherichia coli numbers were decreased from about 40,000 to about 500 cells per mL rinse for all washes in series; two of the tested wash steps (the post defeathering spray wash and the post evisceration brush washer) did significantly lower the numbers of E. coli detected on carcasses. When examined separately, the benefit of broiler carcass wash steps may not be evident. However, when combined with overall processing wash steps can be effective to lessen bacterial contamination on carcasses. This information is useful to processors as they plan interventions steps for maximum effectiveness against bacterial contamination of broiler carcasses.
Technical Abstract: It is unclear how effective different types of broiler carcass wash steps are in lowering the presence or numbers of pathogenic bacteria. We tested for individual and combined effectiveness of five separate on-line wash steps applied between bleed out and chilling in a commercial broiler processing plant. Carcasses were sampled directly before and after each wash step: pre-scald brush washer, post feather pick (New York dressed) spray washer, inside/outside spray washer, post-evisceration brush washer and final pre-chill spray washer. Carcasses were examined for numbers of Campylobacter and E. coli and presence of Salmonella using standard cultural methods. Overall, numbers of Campylobacter were lowered from log 2.58 to log 1.15 CFU/mL carcass rinse but no single wash step caused a significant decrease. While overall Salmonella prevalence was reduced from 80% to 24% as observed for Campylobacter, no wash step caused a significant decrease by itself. The five wash steps in series lowered E. coli numbers from log 4.60 to 2.69 CFU/mL; the New York dressed spray wash and the post evisceration brush washer each had a significant effect on E. coli. When examined separately, the benefit of broiler carcass wash steps may not be evident. However, when combined with overall processing wash steps can be effective to lessen bacterial contamination on carcasses and be useful for pathogen control. Additional studies are necessary to maximize the effectiveness of carcass washers.