Location: Meat Safety & Quality Research
Project Number: 3040-42000-018-09-T
Project Type: Trust Fund Cooperative Agreement
Start Date: Mar 1, 2019
End Date: Sep 30, 2019
The objective is to determine effectiveness of radiant catalytic ionization (RCI), zinc oxide and their combination with zinc oxide nanoparticle treatment on inactivation of Shiga toxin producing Escherichia coli (STEC) and Salmonella on surfaces of fresh beef trimmings and cheek meat.
Twenty-one strains of seven STEC O-groups (O157:H7 and non-O157) and twelve strains of Salmonella including antimicrobial resistant (AMR) and non-AMR strains will be used in this study. Four cocktail mixtures will be inoculated on surfaces of fresh beef to the final concentration of approximately 10,000 to 100,000 CFU/cm2. There will be four treatments: control, ZnO, RCI, and RCI + ZnO. Each treatment will have 10 trim and 10 cheek samples inoculated as described above. The control fresh beef will be treated with sterile saline water using an electrostatic sprayer for 5 to 10 s. The two ZnO treatments will consist of electrostatic spray treatment for 5 to 10 s with ZnO nanoparticles (0.5 mg/ml). The two RCI treatments will last for 0, 15, 30, 60, and 120 s. Control and treated beef trim will be enumerated to determine treatment effectiveness. For STEC and Salmonella, the USMARC chromogenic agar medium will used for enumeration. Aerobic bacteria and Enterobacteriaceae and E. coli will be enumerated using 3M petrifilm and Chromagar EnterobacteriaTM, respectively. The study will be performed with three independent replications.