​Electrolyzed water (EW) is emerging as a popular sanitizer in food industries worldwide. It is produced through the electrolysis of a diluted sodium chloride solution, resulting in two types of water:

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• Acidic Electrolyzed Water (AEW):

  • pH: 2 to 3

  • Redox potential: 1,300 mV

  • Active chlorine concentration: 10 to 90 ppm

• Basic Electrolyzed Water (BEW):

  • pH: 10 to 13

  • Redox potential: 800 to 900 mV

AEW has been shown to reduce bacterial populations by approximately 6.0 log CFU/ml.

 

Importance of Sanitation

Sanitation is crucial in food processing. Common sanitizers include chlorine compounds, organic acids, and quaternary ammonium compounds. While chlorine is effective, it can be more corrosive compared to alternatives like iodine. In the U.S., certain antimicrobial treatments are approved for meat carcasses, but the EU currently restricts these methods due to concerns over chemical residues and effectiveness. EW is gaining traction as a safer alternative for sanitizing food products and surfaces.

 

Historical Context

Originally developed in Russia for medical disinfection, EW has been used in Japan since the 1980s, initially for sterilizing medical instruments. Although its use was limited by a short shelf life, advancements in technology have increased its popularity in the food sector.

 

Production Process

EW is generated by electrolysis of a dilute NaCl or KCl-MgCl2 solution in a cell divided by a membrane. The process involves:

• Voltage: Typically set at 9 to 10 V.

• During electrolysis, NaCl dissociates into negatively charged chlorine ions (Cl-) and positively charged sodium ions (Na+), alongside hydroxide (OH-) and hydrogen ions (H+).

The anode attracts Cl- and OH-, which convert into various gases and acids, while H+ and Na+ move to the cathode, producing hydrogen gas and sodium hydroxide.

In summary, electrolyzed water is becoming a viable and effective sanitizer in the food industry, addressing both hygiene and safety concerns.