Reduction of Escherichia coli O157:H7 on Produce by Use of Electrolyzed Water under Simulated Food Service Operation Conditions

Abstract

Treatment of fresh fruits and vegetables with electrolyzed water (EW) has been shown to kill or reduce foodborne pathogens. We evaluated the efficacy of EW in killing Escherichia coli O157:H7 on iceberg lettuce, cabbage, lemons, and tomatoes by using washing and/or chilling treatments simulating those followed in some food service kitchens. Greatest reduction levels on lettuce were achieved by sequentially washing with 14-A (amperage) acidic EW (AcEW) for 15 or 30 s followed by chilling in 16-A AcEW for 15 min. This procedure reduced the pathogen by 2.8 and 3.0 log CFU per leaf, respectively, whereas washing and chilling with tap water reduced the pathogen by 1.9 and 2.4 log CFU per leaf. Washing cabbage leaves for 15 or 30 s with tap water or 14-A AcEW reduced the pathogen by 2.0 and 3.0 log CFU per leaf and 2.5 to 3.0 log CFU per leaf, respectively. The pathogen was reduced by 4.7 log CFU per lemon by washing with 14-A AcEW and 4.1 and 4.5 log CFU per lemon by washing with tap water for 15 or 30 s. A reduction of 5.3 log CFU per lemon was achieved by washing with 14-A alkaline EW for 15 s prior to washing with 14-A AcEW for 15 s. Washing tomatoes with tap water or 14-A AcEW for 15 s reduced the pathogen by 6.4 and 7.9 log CFU per tomato, respectively. Application of AcEW using procedures mimicking food service operations should help minimize cross-contamination and reduce the risk of E. coli O157:H7 being present on produce at the time of consumption.

Microbiological quality of lettuce (Lactuca sativa) irrigated with wastewater in Addis Ababa, Ethiopia and effect of green salads washing methods

“…Moreover, type of washing (running versus immersion) influences the level of pathogen indicator organisms on fresh produce and therefore influence the final potential risk values. For instance, rinsing under running tap water is considered more effective than immersion, resulting in up to 2.2 log 10 coli reductions (Pangloli et al 2009). In case of helminth eggs, all treatments induced comparable reductions effect, which is mostly based on the physical force of washing and rinsing, not a chemical impact (Amoah et al 2007b;Fallah et al 2012).…”

Efficacy of Neutral Electrolyzed Water for Inactivation of Human Norovirus

“…Electrolyzed water has been evaluated for several food safety industrial applications, including use as a fresh produce wash (12) as well as for cleaning and disinfection in dairy manufacturing clean-in-place systems (13). The antimicrobial efficacy of electrolyzed water is attributed to pH, chlorine content (balance of chlorine gas [Cl 2 ], hypochlorous acid [HOCl], and hypochlorite ion [OCl Ϫ ]), and oxidation-reduction potential (ORP).…”

Potential of Electrolyzed Water as an Alternative Disinfectant Agent in the Fresh-Cut Industry

“…Regarding the fresh-cut industry, since 1999, many reports have demonstrated the potential use of EW as a chlorine substitute for washing fresh fruits and vegetables (Izumi 1999;Koseki and Isobe 2007;Hricova et al 2008;Pangloli et al 2009;Hung et al 2010;Hung 2011, 2013a;Kim and Hung 2012;Olaimat and Holley 2012). Recent studies carried out by our group have evidenced that the use of this technology in the fresh-cut processing line could represent a good alternative to NaOCl Gómez-López et al 2013a.…”