Sodium Fumarate Enhances the Antimicrobial Efficacy of a Commercial Acidic Disinfectant Against Listeria monocytogenes, Escherichia coli and Salmonella Typhimurium Inoculated on Fresh Produce

This study investigated the efficacy of sodium fumarate combined with the commercial organic acid disinfectant NatureSeal FS (FS) against the prominent foodborne pathogens Listeria monocytogenes, Escherichia coli and Salmonella Typhimurium. Sodium fumarate at 10 mM enhanced the antimicrobial activity of FS against overnight cultures of all three pathogens in growth media within 1–5 min. Subsequently, FS supplemented with 25 mM sodium fumarate (pH 2.4) showed enhanced antimicrobial activity by 1–2 log cycles, reaching a total of 2.14–3.22 log cycles within 5 min against the three pathogens inoculated each one individually, on the surface of strawberries, pears and apples compared to a <1.1 log reduction for all control treatments (no treatment, water, 100 ppm chlorine and FS) at pH 2.4. Then, six different organic acid mixes containing key components of FS, two of which were supplemented with 50 and 25 mM sodium fumarate, were tested against the three pathogens, which also performed significantly better than the rest. Sodium fumarate enhanced the efficacy of a commercial acidic disinfectant on fresh produce significantly. The results of this study are highly important for the food industry and consumer protection, as the use of sodium fumarate could significantly enhance the food safety of fresh produce, which is the main contributor to foodborne illness nowadays.