# Application of Electrolyzed Water in the Food Industry: A Review
## 2 Application of Electrolyzed Water in the Food Industry
### Antimicrobial Properties of Electrolyzed Water  
The antimicrobial efficacy of EW is affected by the water's temperature and hardness level. In this regard, the microbial efficacy of SAEW improved with the increased temperature of the water [67, 81]. The antimicrobial efficacy of AEW was evaluated against _Listeria monocytogenes_ and _Salmonella typhimurium_ at 4 \({}^{\circ}\)C and 25 \({}^{\circ}\)C. The results showed the maximum log reduction of more than 8 CFU/mL at 25 \({}^{\circ}\)C [82]. On the contrary, other results showed that preheated SAEW presented a greater log reduction against _Listeria monocytogenes_ and _E. coli_ O157:H7 compared to heated SAEW. The phenomenon has been attributed to the partial loss of ACC while heating [75]. Further research is required to determine the effect of hardness on the properties of EW as limited studies are available. It has been shown that by increasing the hardness level of water, both the free chlorine and the ORP increase, and the decrease in the pH results in the destruction of pathogenic microbes [83]. The increase in water hardness may increase the electrolyte concentration and the electric current or conductivity of the solution and resultantly increase the chlorine production. The factors that affect the properties of EW include voltage, salt concentration, and electrolyte flow rate [83]. It has been concluded that these factors influence the overall attributes of EW, including the sanitizing efficacy. There is a need to develop proper standard operating procedures for the manipulation of EW, and they must be implemented to obtain more benefits from the sanitizing properties of EW. Compared to other toxic chemical sanitizers, EW has shown significant benefits in the food, agriculture, and pharmaceutical industries, as it is produced in an environmentally friendly manner from distilled water and common salt (NaCl). After usage, it returns to its original form without posing any threat to the environment or consumer [71]. EW is advantageous due to its onsite production. Therefore, it can be produced and used without storage. EW has significant antimicrobial properties against a broad range of bacteria and shows non-selective sanitizing properties. Electrolysis units that are sold for industrial and institutional disinfectant use and for municipal water-treatment are known as chlorine generators. It is also hypothesized that EW does not generate antimicrobial resistance in bacteria. As far as the sensory or organoleptic parameters of food are concerned, these remain unaffected while utilizing acidic electrolyzed water (AEW), neutral electrolyzed water (NEW), slightly acidic electrolyzed water (SAEW), and strongly acidic electrolyzed water (StaEW) [66; 71; 73; 77; 78]. Moreover, the cost of EW is negligible compared to its counterparts. The operating cost involves the initial investment of purchasing a generator, along with the water, chemical salts, and electricity expenses [71]. There are a few disadvantages associated with EW, which limit its utilization and applications; hence, attention is required to its possible downsides as well. These downsides include: (i) The chlorine concentration in EW is reduced with time, reducing its bactericidal activity. The reason may be the increased storage time and temperature; therefore, it is suggested that the storage temperature must be low and in closed containers [73]. (ii) The initial investment of the equipment installation and the exhaust system is high, thus limiting the individual applications of EW [71]. (iii) Some generators, when operated below pH 5, release a pungent chlorine odour, which makes it uncomfortable for the operator; therefore, appropriate on-site ventilation is required during operation. (iv) If EW is not supplied continuously with the oxidants Cl2, HOCI, and H\({}^{+}\) through electrolysis, the EW may start to lose its bactericidal potential at a much faster rate [74].