Application of antimicrobials for the elimination of Escherichia coli and Listeria monocytogenes in brine injected beef

Abstract

The application of antimicrobials to a brine-injected raw beef roast for the elimination/inhibition of heat resistant Escherichia coli and Listeria monocytogenes was investigated. The choice of antimicrobials for use in brine injected beef was based on minimum bactericidal concentration in brine solutions. Charsol® and MicocinX™, were added to the brine solution individually and in combination to evaluate possible synergy between the antimicrobials. In the brine solution, numbers of E. coli were not reduced by either antimicrobial; however, L. monocytogenes was reduced by more than 2 log CFU/mL in the presence of either antimicrobial, and no synergistic effect was detected. For the brine-injected beef, neither antimicrobial had any effect on numbers of E. coli, and the counts remained the same during 7 days of storage at 7°C. L. monocytogenes was unaffected by the Charsol®; however, counts were reduced when MicocinX™ was present and growth was inhibited during 4 days of storage.