The goal of this research was to evaluate the efficacy of a novel rechargeable non-leaching polycationic N-halamine coating applied to stainless steel (STEEL) food contact surfaces to reduce Listeria monocytogenes contamination on ready-to-eat (RTE) foods. For this purpose, four L. monocytogenes strains were inoculated onto the charged (C; chlorine-activated) or uncharged (NC) N-halamine coated STEEL coupon surfaces (intact vs. scratched). After inoculation, test surfaces were incubated under different temperatures (2, 10, and 25°C) for different exposure times (0, 48, and 72 h). L. monocytogenes transfer from coated adulterated surfaces to ready to eat meat (beef sausages and roast beef) was also tested at 2 °C. Results showed that both intact-C and scratched-C coated surfaces showed significant reductions at any temperature; however, in presence of organic material, they were more effective in reducing L. monocytogenes at 2 °C and 10 °C than at 25 °C (p < 0.05). In contrast, INTACT-NC and SCRATCHED-NC increased their reduction capability at 25 °C (p < 0.05) decreasing the magnitude of difference of L. monocytogenes reduction with INTACT-C and SCRATCHED-C at the same temperature. Overall, higher L. monocytogenes reduction was observed for INTACT-C and SCRATCHED-C (≈ 4.1 ± 0.19 log CFU/cm2) than INTACT-NC and SCRATCHED-NC (≈ 2.3 ± 0.19 log CFU/cm2) at any temperature (p < 0.05). Additionally, the combination of the surface condition and chlorine presence on the N-halamine coating exposed for 2 h at 2 °C in presence of organic load (50 % meat purge) did not significantly affect the coating bactericidal efficacy. Regarding L. monocytogenes transfer to RTE meat, an overall reduction of ≈ 3.7 logs CFU/g was observed in sausages and roast beef. These findings suggest that a novel rechargeable N-halamine coating on STEEL surfaces has considerable potential to inactivate L. monocytogenes.
KSWFoodWorld
FoodWorld 