“Control of Listeria monocytogenes on Contact Surfaces Through the Application of Enterococcus faecium J19 and Lactobacillus sakei L15”

Abstract

This stud conducted at Texas Tech University evaluates the antimicrobial effectiveness of probiotic lactic acid bacteria, Enterococcus Faecium J19 and Lactobacillus sakei L15, in controlling Listeria monocytogenes on food contact surfaces. Stainless steel and drain-type surfaces were inoculated with a cocktail containing approximately 10⁵ CFU/mL of L. monocytogenes and subsequently treated with three dilutions (1:10, 1:100, and 1:1000) of each probiotic strain. Surfaces were sampled at 0, 6, and 24 hours post-treatment, and bacterial populations were quantified and expressed as log₁₀ CFU/cm². Both strains significantly reduced L. monocytogenes counts, with the greatest reductions observed at higher concentrations. L. sakei L15 exhibited sustained antimicrobial activity, particularly on porous drain surfaces, while E. faecium J19 achieved rapid reductions but showed slight rebounds over time. Statistical analysis revealed significant interactions among treatments, surfaces, and sampling times (p < 0.05). These results demonstrate the potential of LAB-based interventions as biocontrol agents, providing an environmentally friendly alternative or complement to conventional chemical sanitizers in food processing environments.