Fate of foodborne pathogens on green onions and tomatoes by electrolysed water

Aims: To investigate the efficacy of electrolysed water (EW) in killing Escherichia coli O157:H7, Salmonella typhimurium and Listeria monocytogenes on the surfaces of spot-inoculated green onions and tomatoes. Methods and Results: Green onions and tomatoes were inoculated with a cocktail of three strains each of E. coli O157:H7, Salm. typhimurium and L. monocytogenes and treated with acidic electrolysed water (AC-EW), alkaline electrolysed water (AK-EW), alkaline electrolysed water followed by acidic electrolysed water (AK-EW + AC-EW), deionized water followed by acidic electrolysed water (DW + AC-EW) and deionized water (control, DW) for 15 s, 30 s, 1 min, 3 min and 5 min at room temperature (22 +/- 2 degrees C). The relative efficacy of reduction was AC-EW > DW + AC-EW approximate to AK-EW + AC-EW > AK-EW > DW. Conclusions: Acidic EW treatment was able to significantly reduce populations of the three tested pathogens from the surfaces of green onions and tomatoes with increasing exposure time. Significance and Impact of the Study: Rinsing in acidic EW reveals an effective method to control the presence of E. coli O157:H7, Salm. typhimurium and L. monocytogenes on the surfaces of fresh green onions and tomatoes, without affecting their organoleptic characteristics. This indicates its potential application for the decontamination of fresh produce surfaces.