Antibacterial efficacy of nisin, bacteriophage P100 and sodium lactate against Listeria monocytogenes in ready-to-eat sliced pork ham

The effectiveness of bacteriophage P100, nisin and sodium lactate, individually and in combination, in inhibiting Listeria monocytogenes in ready-to-eat pork ham slices was assessed. The antimicrobials were applied to the surfaces of ready-to-eat pork ham slices, which were inoculated with a mixture of L. monocytogenes. Among the individual antimicrobial treatments, bacteriophage P100 was the most effective, decreasing L. monocytogenes to undetectable levels at zero and 72h post-infection. Sodium lactate was the least effective treatment. Treatment with nisin at zeroh significantly reduced initial cell density (p<0.05). However, this pattern was not observed at 72h of storage. A significant difference (p<0.05) existed between the results of separate bacteriophage and nisin treatments after refrigerated storage, but not immediately upon inoculation of the bacteria. The results showed that the use of bacteriophage P100 is the method of choice for the control of bacteria.