Efficacy of bacteriophage treatment in reduction of Salmonella populations on poultry parts

Abstract

In 2011, the Centers for Disease Control and Prevention (CDC) released updated statistics detailing foodborne illness occurrence and attribution in the United States. From this compilation of data, the CDC concluded that approximately 1 out of 6 Americans has succumbed to illness which has been the direct result of consumption of various foodborne pathogens. These numbers translate into approximately 48 million people per year putting tremendous burden on this country’s health care system. Consequently, non-typhoidal Salmonella was responsible for 35% of the hospitalizations due to foodborne illness (Scallan et. al., 2011). Due to the increased prevalence of Salmonella in poultry parts as determined by the base-line parts study conducted by USDA-FSIS, many processors are looking at new multi-hurdle approaches at controlling Salmonella prevalence on poultry products. Bacteriophages are an older technology which has recently made waves in pathogen control due to the presence of many antibiotic-resistant strains of various foodborne pathogens. Recently, USDA-FSIS has given the use of bacteriophages in poultry processing GRAS status (USDA-FSIS, 2014). A new product produced by Intralytix called SalmoFresh™ has been designed to target the top Salmonella serotypes found on poultry products. The first objective of this project was to determine the ideal concentration of SalmoFresh™ in order to give the optimal reduction of Salmonella. Reduction in

Salmonella populations was measured alongside 100ppm and 700ppm peracetic acid (PAA). Results suggested that that 9.602 log PFU/sample phage concentration would be optimal to use in a plant setting. The second objective of the project was then to combine the optimized SalmoFresh™ concentration with a 8) post-chill intervention. This was designed in order to give the best reduction in Salmonella cell counts in a plant setting. From this, the results suggested that 90ppm PAA in combination with a 9.602 log PFU/sample phage spray treatment gave the most significant reduction in Salmonella populations after a 24 hour period. In conclusion, experimental evidence suggests that using bacteriophage treatment in combination with currently used chemical interventions can provide optimal control of Salmonella on poultry parts. These results opens a new door as to adding a new multi-hurdle approach to foodborne illness control in the plant in various different locations.