Comparison of antimicrobial efficacy of multiple beef hide decontamination strategies to reduce levels of Escherichia coli O157:H7 and Salmonella.

This study involved a comparison of the antimicrobial efficacy of several beef hide decontamination interventions to identify those that more effectively reduced levels of Escherichia coli O157:H7 and Salmonella. Whole beef hides were inoculated with E. coli O157:H7 and Salmonella and decontaminated with sprays of solutions of acetic acid (AA; 10%, 55 degrees C), lactic acid (LA; 10%, 55 degrees C), sodium hydroxide (SH; 3%, 23 degrees C), sodium metasilicate (SM; 4%, 23 degrees C), or sodium hydroxide (1.5%), followed by high-pressure washing with chlorinated (0.02%) water (SHC; both applied at 23 degrees C) or water (W; 23 degrees C) or by deluging with solutions of potassium cyanate (PC; 2.4%, 30 degrees C) or sodium sulfide (SS; 6.2%, 30 degrees C). All spraying treatments (AA, LA, SH, SM, and SHC) resulted in removal of visual organic material, whereas the dehairing treatments (PC and SS) successfully removed hair along with visual organic material. The PC, SS, and SHC treatments resulted in the greatest reductions of E. coli O157:H7 (P < 0.05), by 5.1, 4.8, and 5.0 log CFU/cm2, respectively. The SS and SHC treatments decreased Salmonella by 4.2 and 4.4 log CFU/cm2, respectively, compared with the water treatment, which reduced levels by 1.7 log CFU/cm2 (P < 0.05). The SH, AA, and LA treatments also lowered both E. coli O157:H7 and Salmonella by at least 2.0 log CFU/cm2. The treatments that were effective in this study deserve further consideration for commercial implementation as hide decontamination interventions.