# Non-Thermal Methods for Ensuring the Microbiological Quality and Safety of Seafood
## 6 Electrolyzed Water--EW  
### General Description of EW Technology  
Cross-contamination of food and seafood products remains a major problem for the food industry that needs to be solved. Although numerous effective techniques have been developed or improved in recent years, effective sanitizers are widely used for the inactivation of foodborne pathogens that commonly contaminate the food during the different processing stages or preparation of final products [189; 190]. However, it is commonly accepted that common sanitizers used are becoming less effective against resistant microorganisms, may have high cost, and can produce chemical residues. Therefore, the food processors and food safety experts must use innovative, safer, and more effective sanitizers to surpass the problems mentioned above. Electrolyzed water (EW) is considered a new non-thermal and environmentally friendly food sanitizer [6; 191]. Electrolyzed Water (EW) is produced by a process where electricity is used to make a chemical change called electrolysis. The electrolysis occurs in a specially designed chamber containing water with dissolved sodium chloride (NaCl). However, this process is not spontaneous, and electrical power from a generator passes through the submerged electrodes (separated by a membrane) in the solution [192]. In the EW generator, the voltage and current values are normally set at 9-10 V and 8-10 A, respectively [193]. During the process of electrolysis, NaCl is breaking apart into sodium metal (Na) and chlorine gas (Cl\({}_{2}\)), while water (H\({}_{2}\)O) is breaking apart using electrolysis into hydrogen (H\({}_{2}\)) and oxygen (O\({}_{2}\)) gasses. Analytically, the negatively charged ions of chloride (Cl\({}^{-}\)) and hydroxide (OH\({}^{-}\)) are losing their electrons (e\({}^{-}\)) through the anode of the EW generator. During this oxidation process, hypochlorous acid (HOCI), hypochlorite ion (-OCI), hydrochloric acid (HCl), oxygen gas (O\({}_{2}\)), and chlorine gas (Cl\({}_{2}\)) are generated. On the opposite, positively charged ions (Na\({}^{+}\) and H\({}^{+}\)) gain electrons (e\({}^{-}\)) pushed out the cathode, and reduction takes place, resulting in the generation of sodium hydroxide (NaOH) and hydrogen gas (H\({}_{2}\)). Inside the chamber, two types of EW are produced: (1) at the anode, acidic electrolyzed water (AEW) or electrolyzed oxidizing water (EOW) with pH value 2-3, oxidation-reduction potential (ORP) >1100 mV, and available chlorine concentration (ACC) of 10 to 90 ppm, and (2) at the cathode, basic electrolyzed oxidizing water (BEW) with pH value ranging from 10 to 13 and ORP of \(-\)800 to \(-\)900 mV is generated [15]. Meanwhile, other solutions of EW have been reported and used, such as neutral electrolyzed water (NEW) with a pH value of 7-8, and ORP equal to 750 to 900 mV, produced in a single cell chamber and the anodic solution is mixed with OH\({}^{-}\)[193]. Slightly acidified electrolyzed water (SAEW) with a pH value of 5-6.5 and ORP of nearly 850 mV [194] is also produced in a single cell chamber by the electrolysis of HCl alone or in combination with NaCl. The most common types of EW currently used for their desirable effects are summarized in Table 4. The physicochemical effects of the generated EW may vary depending on the type and concentration of the solution, voltage and current value, water flow, and time of electrolysis [192]. EW shows high antimicrobial activity against the most common bacteria, spores, fungi, and viruses found on food and the general environment of food processing plants and has a minimal effect on the physicochemical and sensory quality of the food [204, 205, 206, 207, 208, 209]. The antimicrobial activity and the mode of action of EW against bacteria are still not fully described. However, it is known that chlorine and reactive oxygen can disrupt the microbial cell membrane and cause oxidative damage to DNA [210].