Phage-mediated Biocontrol of Salmonella enterica ser. Typhimurium in Bacon

Foodborne illnesses caused by Salmonella have long been a global public health concern. Whether through contaminated meat or water, or undercooked food, this poses a problem to countries like the Philippines that consume pork and chicken frequently. This study isolated three Salmonella enterica ser. Typhimurium phages (svBEATS-5, -6, and -9) from sewage samples to assess their potential biocontrol use against Salmonella Typhimurium in commercially bought bacon. The phages were characterized based on pH and thermal stability, and host range. Ideal conditions for the phages were identified at pH 7 and 37°C, with the most stable phages, svBEATS-5 and svBEATS-6, exhibiting similar lytic activity at all pH levels and temperatures. To evaluate their efficacy as biocontrol agents, a phage cocktail comprising the three phages was applied over bacon spiked with S. enterica Typhimurium at 4°C and 30°C. Results showed that at both temperatures, the concentration of Salmonella Typhimurium decreased in vitro and meat samples, with a more significant reduction under refrigerated conditions. In addition, the phages could maintain viable concentrations at temperatures, 4°C and 30°C. The results suggest that the phages can be employed to control Salmonella Typhimurium in bacon and can be a viable alternative to using antimicrobials in bacon and other meat products.