Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: April 27, 2005
Publication Date: May 12, 2005
Citation: Patel, J.R., Solomon, M.B. 2005. Effect of hydrodynamic pressure processing on inactivation of pathogenic bacteria attached to beef muscle [abstract]. BARC Poster Day. Paper No. 44. Technical Abstract: The bactericidal effect of hydrodynamic pressure processing (HDP) on Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated on beef cubes was evaluated. The effect of HDP on loosely attached or planktonic cells (analyzed first by running diluent over the beef cubes) and strongly attached (analyzed again rinsed cubes by pummeling for 2 min in diluent) was studied. Irradiated 1” beef cubes (N = 54) were dipped in individual bacterial suspensions, air dried, vacuum packed, and treated with HDP using 100 g binary explosive placed 12” from meat surface in a 54-L stainless steel shockwave container. Total E. coli O157:H7 populations were more sensitive to the HDP treatment (0.44 log10 CFU/g reduction) followed by S. Typhimurium (0.35 log10 CFU/g) and L. monocytogenes (0.26 log10 CFU/g). Further, bacteria strongly attached to beef surface were inactivated by HDP at a greater rate and the reduction was significant for all three bacteria attached strongly to the beef surface (0.53, 0.41, and 0.45 log10 CFU/g for E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively). No clear indications were obtained for sublethal damage of microorganisms surviving the HDP treatment. These findings disclose that HDP treatment is more lethal to pathogenic bacteria strongly attached to beef surface compared to those planktonic or loosely attached cells.