Physicochemical and antibacterial effects of sodium bicarbonate and brine water on the electrolysed water generated by a portable sanitising unit

A novel method was used to produce near neutral pH electrolysed water (NEW) by developing a portable electrochemical sanitising unit that uses diluted sodium chloride and sodium bicarbonate solution (6 mM) as electrolytes. The unit produced NEW at pH 5.70 to 7.1, an oxidation-reduction potential of 802.2-933.8 mV, and free available chlorine (FAC) of 3.3-70 mg/L. NEW produced by the unit with NaCl 10 g/L showed stronger bactericidal effects than NEW produced by mixing the anode and cathode product from commercial unit's (P < 0.05): 2.03 log colony forming units (CFU)/mL reductions compared with 1.66 log CFU/mL reductions. To further understand the sanitising result, electron spin resonance and flow cytometry were performed. The results showed NEW produced by the developed unit induced 82.2% injured cells compared with 54.4% by NEW without detected free radicals. Overall, the current efficiency and power consumption were increased during NEW generation for NEW using sodium bicarbonate compared with sole NEW. The developed NEW generator is a promising sanitising unit for consumers and food industry to control foodborne pathogens.