APPLICATION OF CARNATROL(TM) AND TIMSEN(TM) TO DECONTAMINATE BEEF

The spray application of two commercial decontaminating agents for red ucing bacterial populations associated with fecal contamination on bee f was examined in two separate experiments. Individual pieces of preri gor lean beef tissue were inoculated with fresh bovine feces and subje cted to a 15-s spray wash (75 Ib/in(2), 20 degrees C) with water or va rious concentrations of Carnatrol(TM), composed of copper sulfate pent ahydrate, or Timsen(TM), 40% N-alkyldimethylbenzylammonium chloride in 60% stabilized urea, and stored under refrigerated (5 degrees C) cond itions. When Carnatrol(TM) was applied to beef tissue at 20, 40, and 8 0 ppm, bacterial populations were not statistically different (P great er than or equal to 0.05) than water-treated populations at days 0, 1, and 2. When Carnatrol(TM) was applied to tissues at 160 ppm, bacteria l populations were statistically different (P less than or equal to 0. 05) from water-treated tissue on all of the days examined; however, re ductions were not greater than 0.58, 0.42, and 0.35 log CFU/cm(2) at d ays 0, 1, and 2, respectively. Remaining bacterial populations resulti ng from spray applications of Timsen(TM) to tissues at 200, 400, and 8 00 ppm were not statistically different than remaining bacterial popul ations of water-treated tissues at days 0, 1, 2, or 3. Reductions in b acterial populations associated with Timsen(TM) were no greater than 0 .40 log CFU/cm(2) on any of the days examined. This study demonstrates that under conditions used in this study, spray washes with either of the two commercially available decontaminating agents were no more ef fective than water washes for reducing bacterial populations associate d with fecal contamination on beef tissue.