Validation of Various Antimicrobial Solutions on the Reductions of Surface Microbial Load of E. Coli O157:H7 on Lean Beef

A study was conducted to examine the effectiveness of several antimicrobial products of differing chemistries in order to determine the most effective solutions that can be applied to varying industry situations. Antimicrobials (n=14) were tested for effectiveness on lean beef surfaces (5.08 cm diameter, 0.4 cm thick) within a Ross TC 700MC tenderizer (Ross Industries, Midland, VA) equipped with a Dosatron (Clearwater, FL) custom-built spray cabinet. Lean beef wafers (n=80) for each antimicrobial, which were fabricated from boneless top butt sirloins (IMPS #184), were subjected to spray treatment within this piece of equipment. Prior to treatment, samples were inoculated with 0.1 mL of 2 X 108 CFU/ml of E. coli O157:H7 cocktail (ATCC 43890, ATCC 43894, ATCC 43895, ATCC 35150). After processing samples were plated in order to achieve surface reduction effectiveness of each antimicrobial at 1 h, 1 d, 7 d, and 14 d post treatment. BeefXide was the most effective (P < 0.05) antimicrobial at 1 hr post processing. AvGard-Xp, AFTEC 3000, and Cytoguard Plus were the most effective (P < 0.05) antimicrobials at surface reduction after 1 day of vacuum-sealed, refrigerated storage (2o C). After 7 days of storage (2o C) under the same conditions AvGard-XP was the most effective (P < 0.05) at reduction of E. coli O157:H7, AvGard-XP remained the most effective (P < 0.05) antimicrobial tested after 14 days of storage.Department of Animal Scienc