Reducing pathogens by using zinc oxide nanoparticles and acetic acid in sheep meat.

Practical applications of different concentrations (0, 1, 2, 4, 6, and 8 mM) of zinc oxide (ZnO) suspensions containing 1 % acetic acid were investigated against the pathogenic bacteria Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Bacillus cereus. ZnO suspensions (0, 1, 3, 6, and 8 mM) containing acetic acid had a significant inhibitory effect on the growth of L. monocytogenes, E. coli, and S. aureus during 12 h of incubation, and the 8 mM suspensions of ZnO were the most effective against all the strains. These data suggested that the antibacterial activity of ZnO was concentration dependent. Thus, 6 and 8 mM ZnO were selected for further studies in meat. ZnO nanoparticles reduced initial growth of all inoculated strains in meat. To our knowledge, this is the first report describing the antibacterial activity of ZnO nanoparticles in meat and indicates the potential of these nanoparticles as an antibacterial agent in the food industry.