Submitted to: Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: March 21, 2007
Publication Date: July 28, 2007
Citation: Patel, J.R., Sanglay, G.C., Solomon, M.B. 2007. Hydrodynamic pressure processing and antimicrobials for control of Listeria monocytogenes on frankfurters [abstract]. Institute of Food Technologists. Paper No. 98-29. Technical Abstract: Ready-to-eat (RTE) meat products have been implicated as sources of Listeria monocytogenes in humans. The safety of RTE meats can be enhanced by antimicrobials and post-packaging treatments to control the growth of L. monocytogenes. The objective was to determine the antilisterial activity of sodium lactate (SL), sodium diacetate (SD) and nisin (N) on frankfurters in combination with hydrodynamic pressure processing (HDP). Minimum inhibitory concentration of five L. monocytogenes strains as determined in tryptic soy broth was >6 percent, 0.4 percent, and 300 IU/ml for SL, SD, and N, respectively. Frankfurters were surface inoculated with a five-strain mixture of L. monocytogenes after dipping in (1) control (sterile water), (2) 10 percent SL, (3) 5 percent SD, (4) SL+SD, (5) N (5000 IU/ml), (6) N+SL, (7) N+SD, and (8) N+SL+SD for 5 minutes. The frankfurters were vacuum packed and treated with or without hydrodynamic pressure (HDP). Frankfurters were periodically analyzed for pH, L. monocytogenes (MOX), and aerobic (TSAYE) cell populations during storage of 28 days at 4°C. HDP treatment significantly reduced L. monocytogenes populations in frankfurters. Dipping treatments containing nisin showed greater L. monocytogenes reduction compared to that with sodium lactate and/or sodium diacetate, however, the difference was not significant. The combination of nisin and HDP treatment resulted in more than 2 log reduction in L. monocytogenes populations after storage of 28 days. There was a synergistic effect between nisin and HDP for inhibition of L. monocytogenes. The reduction pattern in aerobic cell populations during storage of antimicrobials and HDP treated frankfurters was similar to that of L. monocytogenes reduction. These results indicate that the use of nisin as a dipping treatment followed by HDP treatment is effective for inhibition of the pathogen during storage at 4°C.