11: EOW

Question 1

How is EOW generated?

Answer 1

• By passing electric current to a dilute salt solution, which causes the electrolysis of salt (NaCl, KCl, MgCl2) solutions.

Question 2

What are the three types of EOW?

Answer 2

• Acidic electrolyzed water
• Alkaline electrolyzed water
• Neutral electrolyzed water

Question 3

Acidic EOW is thought to possess the strongest bactericidal effect. Why is that?

Answer 3

• Low pH increases susceptibility of cells to chlorine and hypochlorous acid (HOCL)
• High redox potential causes cell membrane damage, change normal electron flow and generates free radicals.
• Active chlorine content react with nucleic acid and destroy key metabolic enzymes.

Question 4

What are the factors affecting the antimicrobial activity of EOW?

Answer 4

• pH
• Temperature
• Exposure time
• Active chlorine content
• Type of medium

Question 5

Why isn’t acidic EOW used a lot in the industry despite its strong bactericidal effects?

Answer 5

• Extreme pH and high active chlorine content in acidic EOW compromises the food quality.
• High chlorine concentration is corrosive.
• Reaction between hypochlorous acid and hypochlorite with organic compounds produce toxic compounds.
• Neutral EOW has longer shelf-life, slightly acidic EOW is safer and has less detrimental effects.

Question 6

What are the applications of EOW?

Answer 6

• Used synergistically with antimicrobial processes, e.g., ultrasound, UV, chemical and heat treatment
• Cleaning in place (CIP)
• Post harvesting management to inactivate spoilage microorganisms.