Efficacy of peroxy acetic acid in reducing Salmonella and Campylobacter spp. populations on chicken breast fillets

Authors: KUMAR, S - University Of Georgia; SINGH, M - University Of Georgia; Cosby, Douglas; Cox Jr, Nelson; THIPPAREDDI, H - University Of Georgia

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/19/2019
Publication Date: 12/30/2019
Citation: Kumar, S., Sing, M., Cosby, D.E., Cox Jr, N.A., Thippareddi, H. 2019. Efficacy of peroxy acetic acid in reducing Salmonella and Campylobacter spp. populations on chicken breast fillets. Poultry Science. 99:2655–2661. https://doi.org/10.1016/j.psj.2019.12.045.
DOI: https://doi.org/10.1016/j.psj.2019.12.045

Interpretive Summary: As poultry processors seek to improve the quality of and eliminate human pathogens from poultry products, various chemicals are being evaluated to achieve the performance standards set by USDA, FSIS. Peroxy acetic acid (PAA) is a chemical commonly used for this purpose. In this study, chicken breast fillets were inoculated with Salmonella and Campylobacter, which were allowed time to attach, and washed with various concentrations of PAA either in a dip tank or as a spray solution. The breast fillets were then tested for the number of Salmonella or Campylobacter remaining. Both application methods were capable of reducing both Salmonella and Campylobacter on the breast fillets. Use of this chemical in the processing plant may improve the microbial safety of chicken breast fillets.

Technical Abstract: Poultry processors have incorporated several antimicrobial interventions to reduce Salmonella and Campylobacter prevalence on poultry and poultry parts to meet USDA FSIS performance standards. Efficacy of peroxy acetic acid (PAA) in reducing of Salmonella and Campylobacter populations on chicken breast fillets was evaluated for different exposure times, using either a spray or an immersion application method. Fresh chicken breast fillets were inoculated with a cocktail (ca. 7 log10 CFU/mL) of nalidixic acid resistant Salmonella Typhimurium (STNR) and gentamycin resistant Campylobacter coli (CCGR) strains and held for 30 min to allow bacterial attachment. PAA solution (100, 200, 500 or 1,000 ppm) was applied on the inoculated breast fillets using either as an immersion (4, 10 and 30 s) or spray (5 and 10 s) method. The breast fillets were manually rinsed with 100 mL of buffered peptone water (BPW containing 0.1% sodium thiosulfate) and serial dilutions were prepared in peptone water (PW, 0.1%). Appropriate dilutions were plated on Campy-Cefex agar containing 200 ppm gentamycin and incubated microaerobically (5% O2, 10% CO2 and 85% N2) for 48 h at 42° C to enumerate Campylobacter populations. For Salmonella enumeration, all dilutions were performed in PW containing nalidixic acid (200 ppm; PWNA) and plated on Petrifilm APC plates and incubated at 35° C for 48 h. Both immersion and spray applications reduced (P = 0.05) the Salmonella and Campylobacter populations compared to the control. Increasing the PAA concentration to 250, 500 and 1,000 ppm resulted in greater reductions (P = 0.05) in Salmonella and Campylobacter populations. Immersion of the inoculated breast fillet in 1,000 ppm PAA solution for 30 s resulted in Salmonella and Campylobacter population reductions of 1.92 and 1.87 log CFU/mL, respectively. Method of antimicrobial application (immersion and spray) did not affect the reductions in Salmonella and Campylobacter populations. Either immersion or spray application can be used to improve microbial safety of chicken breast fillets in a poultry processing plant.