Purpose: The purpose of this study was to evaluate the reductions in Salmonella and Campylobacterpopulations on raw poultry parts and trim due to USDA approved antimicrobial treatments.
Methods: Raw, boneless, skinless chicken leg meat was portioned (50 g), and inoculated with Salmonella (five-strains; 5.0-5.8 log/g) or tested for Campylobacter (contamination from the slaughter process). Samples (n = 10) were immersed in acidified sodium chlorite (ASC; acidifiers sodium acid sulfate or citric acid, 900-1000 ppm, pH 2.7-2.8), peroxyoctanoic/peroxyacetic acid mixture (POA; 90-100 ppm and 180-200 ppm), and peroxyacetic acid (PAA; 90-100 ppm) for 15 s, 30 s, or 60 s. After treatment, samples were neutralized in 50 ml of Dey Engley broth (Salmonella) or rinsed with phosphate buffered diluent water (Campylobacter). Appropriate serial dilutions were plated onto Salmonella-Shigella agar and Campy-CEFEX agar for Salmonella and Campylobacterenumeration, respectively. Data were analyzed using the general linear model (counts) or a chi-square test (incidence) and means were separated using Tukey’s method (α = 0.05).
Results: Antimicrobial selection and exposure time are key influences to achieving Salmonella and Campylobacter reductions on poultry parts and trim. All antimicrobial applications tests reduced (P < 0.05) Salmonella populations from inoculated levels of 5.8 ± 0.1 log CFU/g. Specifically for ASC, the fewest Salmonella (4.1 ± 0.5 log CFU/g) were recovered from samples treated for 15 s when CA was the acidifier; however, a comparable result (4.2 ± 0.2 log CFU/g) was achieved when SAS was the acidifier and samples were treated for 30 and 60 s. The lowest concentration of POA (90-100 ppm) at shortest immersion time (15 s) tested reduced (P < 0.05) Salmonella inoculated onto parts to 4.5 ± 0.5 log CFU/g. Increasing the POA concentration to 190-200 ppm, however, did not increase its efficacy. Treatment of uninoculated parts with POA (90-100 ppm) reduced (P < 0.05) Campylobacterincidence from 80.0% to 20.0% and populations from 0.7 ± 0.8 to 0.1 ± 0.1 log CFU/g.
Significance: These data and application parameters can be used to support and validate antimicrobial treatments for poultry parts and trim in secondary processing prior to packaging or grind process to meet current and future USDA regulatory standards.