Evaluation of commercial antimicrobials against stress-adapted Campylobacter jejuni on broiler wings by using immersion and electrostatic spray and an economic feasibility analysis

This study compares the efficacy of commercial antimicrobials to inactivate unstressed and stress-adapted Campylobacter jejuni on broiler wings using immersion and electrostatic spray and evaluates the economic feasibility of the two methods. Overnight cultures (18 h) were prepared from three strains of C. jejuni that were either unstressed, acid stressed (AS, 2 h in pH 5 Bolton broth), starvation stressed (SS, 2 h in 0.9% saline solution), or cold stressed (CS, 5 days in Bolton broth at 4 °C). Unstressed or stress-adapted C. jejuni cells were inoculated onto fresh chicken wings, which were kept untreated (control), immersed in or electrostatically sprayed with peroxyacetic acid (PAA-0.1%), lactic acid (LA-5%), lactic and citric acid blend (LCA-2.5%), sodium hypochlorite (SH-70 ppm), or a mixture of PAA-H2O2 (SaniDate®-5.0, SD-0.25%) for 30 s. Surviving bacteria were recovered onto Brucella agar under microaerophilic conditions. Economic feasibility analysis was performed based on the assumption of ∼1500 wings annually from very small poultry plants. There was no difference in the inactivation of C. jejuni cells between immersion and electrostatic spray (P > 0.05). Cross-protection was developed in AS (0.1–0.6 log CFU/g) and SS (0.8–1.8 log CFU/g) samples that affected pathogen recovery during subsequent exposure to antimicrobials by immersion or electrostatic spray. Among all stressed cultures, different degrees of inactivation (P < 0.05) were shown in the samples treated with PAA (0.3–2.5 log CFU/g), LA (0.8–2.3 log CFU/g), LCA (0.6–2.4 log CFU/g), SH (0.3–2.2 log CFU/g), and SD (0.1–2.3 log CFU/g) compared with the control. The economic benefits of the electrostatic spraying become more evident as the scale of production increases. For small producers, immersion is the suggested method since it is more economic than electrostatic spraying.