Evaluation of Hand-Trimming, Various Sanitizing Agents, and Hot Water Spray-Washing as Decontamination Interventions for Beef Brisket Adipose Tissue

Abstract

Various chemical solutions (5% hydrogen peroxide, 0.5% ozone, 12% trisodium phosphate, 2% acetic acid, and 0.3% commercial sanitizer), water (16 to 74°C) spray-washing interventions, and hand-trimming/spray-washing treatments were compared for their ability to remove fecal material and to reduce bacterial contamination on beef brisket fat samples in a model spray-washing cabinet. The samples were inoculated with 2.5 cm2 of a bovine fecal paste inoculated with Escherichia coli (ATCC 11370). Hand-trimming followed by spray-washing with plain water (16 to 74°C when it came in contact with the sample; 20.68 bar pressure; for 36 or 12 s corresponding to chain speeds of 100 or 300 carcasses per h) lowered (P < 0.05) microbiological counts, compared to the inoculated control, by 1.41 to 2.50 log colony-forming units (CFU)/cm2. Additionally, spraying with chemical solutions (16°C; 1.38 bar, 12 or 36 s), before or after spray-washing with plain water (20.68 bar) of 16°C (36 s), 35°C (12 s) or 74°C (12 s) reduced bacterial counts by 1.34 to 2.87, 1.18 to 2.86, or 0.96 to 3.42 log CFU/cm2, respectively. Reduction in counts was influenced by water temperature (16 to 74°C), type of chemical solution, and sequence of spray application. Under the conditions of this study, hydrogen peroxide and ozonated water were more effective (P < 0.05) than trisodium phosphate, acetic acid, and a commercial sanitizer when applied after first washing with plain water. Trisodium phosphate maintained its activity when used before washing with water. In general, water of 74°C caused reductions (P < 0.05) exceeding 3.0 log CFU/cm2, which were higher than those achieved by trimming and spray-washing. No spreading of bacteria in areas immediately adjacent to the inoculation site was detected following spray-washing.