Purpose: Evaluate the viability and survival of Salmonella spp., and Listeria monocytogenesafter inoculation on four different surfaces, including: two different copper-based alloys 1) C710, Cu 79% - Ni 21%, 2) C706, Cu 88.6% - Fe 1.4% - Ni 10%; and two common processing plant surfaces, 3) stainless steel (SS); and, 4) Teflon (TF).
Methods: Survival tests were conducted under controlled conditions at 8°C and 80% of RH. Surfaces were evaluated under clean and coated conditions (chicken fat). Over 230 coupons of 4 cm2 were inoculated individually with a cocktail of each pathogen with a target concentration of 6.5 log10 (CFU/cm2) separately, and, the survivors were quantified at different time intervals (within 32 h) in order to determine the decimal time (D-value).
Results: No survivors were recovered from the dry and clean C706 surfaces (D-value of 0 h). The C710 eliminated L. monocytogenes instantaneously and had a D-value of 0.5 h for Salmonellaspp. Clean and dry SS and TF had D-values higher than 8 h (P < 0.05). The presence of chicken fat increases the survival of the pathogens by protecting them from the contact with the antimicrobial surfaces and partial desiccation. However, in the presence of chicken fat, copper containing surfaces performed better that the clean SS and TF.
Significance: Copper containing alloy surfaces are effective at inactivating Listeria monocytogenes and Salmonella spp. under simulated commercial conditions and can potentially be used to control the persistence of foodborne pathogens in ready-to-eat environments.