Spray-washing/rinsing treatments utilizing warm/hot water and/or acetic acid solution were evaluated separately and in sequence for their efficacy in reducing microbial contamination on beef tissue inoculated with Escherichia coli. Treatments reduced the aerobic plate (APC) and E. coli counts of the samples inoculated to have 5.0-7.4 log CFU/cm 2 (APC) by 1.1 to 4.3 logs. Similarly, most treatments reduced APC and total coliform counts of samples inoculated to have 1.8-3.7 log CFU/cm 2 (APC) by 0.1 to 1.7 logs. Combinations involving 3 or 4 treatments were more effective in reducing bacterial contamination than single-or 2-treatment combinations.

A field study was conducted to compare trimming/washing procedures with hot-water rinsing as interventions for beef carcass decontamination. Treatments included no trimming/no washing; knife-trimming followed by spray-washing (26ЊC, 276 kPa followed by 1000 kPa); and hot-water rinsing (Ͼ77ЊC, 138-152 kPa, 2.5 or 8 sec) following either knife-trimming or no knife-trimming of the contaminated site and spray-washing. Samples were analyzed for counts of total aerobic bacteria, total coliforms and Escherichia coli, as well as for the presence of Salmonella spp. and E. coli O157:H7. Results indicated decontamination of beef carcasses could be achieved by knife-trimming followed by spray-washing or by spray-washing followed by hot-water rinsing.