Reciprocal Meat Conference Abstracts

Efficiency of Phage Intervention on Salmonella Kill on Lean Pork, Pork Trim and Bacon

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Abstract

ObjectivesRaw Pork Products Exploratory Sampling Program (2015) by FSIS, USDA aims to estimate the prevalence and levels of Salmonella in various fresh pork cuts and products. The results of this ongoing baseline sampling program will provide direction to FSIS and the Agency to develop a better risk profile and refine the present food safety guidelines for pork products. New impending regulatory standards will likely prompt establishments to seek interventions that can help in reducing the prevalence and most probable number of Salmonella in their products.Bacteriophages are ubiquitous antibacterial agents that can invade and kill specific target pathogenic bacteria in foods. PhageGuard S, is a commercial salmonella based phage cocktail consisting of 2 phages, FO1a and S16. Having been found in nature, these phages are a natural and organic way to kill salmonella and reduce risk in various types of food products. Phage have a number of other added benefits over traditional chemical processing aids as well. There is no impact to the sensorial properties of foods and no impact on worker safety, wastewater or processing equipment. As such, the use of Salmonella-phages as a biocontrol agent for Salmonella can be an interesting avenue to explore for the meat industry.This study determines the efficacy of a commercially available phage product, PhageGuard S, for Salmonella kill on several types of pork including– lean meat, bacon and pork trim.Materials and MethodsOvernight culture of Salmonella Se13 streptomycin resistant strain was diluted and inoculated at a concentration of 2 × 104 CFU/cm2 or CFU/g on lean pork, bacon or pork trims (duplicate samples per treatment). Subsequently, contaminated samples were treated with either of the following phage concentrations (5 × 106, 1 × 107, 2 × 107 or 5 × 107 PFU/cm2 or PFU/g) or water (control). After treatment, samples were stored at 40°F (4°C) for 18 h before retrieval and enumeration of bacteria on selective agar plates.ResultsThe application of phages 107 and 5 × 107 PFU (Plaque Forming Unit)/cm2 on lean pork resulted in 1.1 log10 CFU/cm2 and 1.6 log10 CFU/cm2 reduction of Salmonella respectively (mean value of 2 individual experiments). On Bacon, the highest phage concentration showed Salmonella reduction of 1.3 log10 CFU/cm2 and the lowest phage concentration resulted in 0.8 log10 CFU/cm2 reduction (mean value of 2 individual experiments). When applied on pork trim, phage concentration 2 × 107 and 5 × 107 PFU/g showed Salmonella kill of 1.3 log10 CFU/g and 1.7 log10 CFU/g, respectively. Overall, a dose response was observed where increasing phage concentration resulted in an increasing Salmonella kill on different pork meat.ConclusionPhage technology is an easy, safe intervention and an alternative to chemicals and antibiotics in controlling of Salmonella in slaughter and processing environments. The above results indicate that the commercially available phage solution, PhageGuard S, can reduce Salmonella contamination on pork by 1.3 to 1.7 log10. Therefore, making it an effective Salmonella intervention for processors to reduce risks and allow for increase in consumer safety.

Keywords: salmonella, Trim, pork, Bacteriophage, bacon

How to Cite:

Sirdesai, S., Eraclio, G., Peterson, R., van Mierlo, J. & De Vegt, B., (2018) “Efficiency of Phage Intervention on Salmonella Kill on Lean Pork, Pork Trim and Bacon”, Meat and Muscle Biology 2(2). doi: https://doi.org/10.221751/rmc2018.137