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Bactericidal activity of neutral electrolyzed water (NEW) was investigated against endospore forming Bacillus cereus and Clostridium perfringens in cell suspensions and artificially inoculated onto the surface of selected fresh produce items (cherry tomato, miniature cucumber, carrot and parsley) and polypropylene cutting boards at ambient temperature (22 °C). Viable counts of survivors were determined within 0 (untreated control), 1, 3 and 5 min of treatment at ambient temperature using NEW solutions of 60 and 120 mg/L free available chlorine FAC. All treatments showed significant differences (P 0.05) after 5 min of treatment, whereas bacterial viability of the inoculated produce was reduced by 2.11–2.30 and 2.41–3.16 log10 CFU/g when NEW used at 120 mg/L FAC for B. cereus and C. perfringens, respectively. When inoculated cutting boards were sprayed with NEW at 120 mg/L FAC and after 5 min of treatment, cell viability was reduced by 2.33 and 3.06 log10 per 100 cm2 for B. cereus and C. perfringens, respectively. This study showed that NEW could be used as an effective bactericidal treatment alternative to commonly used chemical sanitizers against endospore forming bacteria.

This study investigated the effect of electrolyzed water on pathogenic bacteria cell suspensions. Specifically, we evaluated the efficacy of strong and weak acidic electrolyzed waters (SACEW, WACEW) and strong and weak alkaline electrolyzed waters (SALEW, WALEW) on Vibrio parahaemolyticus, Listeria monocytogenes, Aeromonas hydrophila, Campylobacter jejuni, and Escherichia coli O104:H4 in suspensions of (10 7 e10 9 CFU/mL) in 1% NaCl. SACEW and WACEW were applied at available chlorine concentrations (ACC) of 20 and 10 mg/mL, pH 3.1 and 3.55 and oxidation-reduction potentials (ORP) of 1150 and 950 mV, respectively. Results show that no viable cells were recovered for V. parahaemolyticus, L. monocytogenes, A. hydrophila, C. jejuni within 2 min at 20 � C. However, E. coli O104:H4 was significantly more resistant to ALEW compared to ACEW. Results also show that the bactericidal activity of SACEW (20 mg/mL ACC) was more effective than WACEW (10 mg/mL ACC) in terms of inactivating E. coli O104:H4. Alkalineelectrolyzed waters were found to reduce cell numbers by 1e3 log (P < 0.05). However, alkaline electrolyzed water was less effective (P < 0.05) than acidic electrolyzed treatment.