Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan
Seawater in a fishing port was electrolyzed to induce hypochlorite up to approximately 1 mg/L for the reduction of viable bacterial count because disinfection of seawater is important for the prevention and control of hazards in seafoods. The number of viable bacteria in a fish holding tank was lowered from 104-105 mg/L to 100-101 mg/L after electrolization of seawater and the low level of viable bacterial count was kept for at least 3 hours. The reduction rate of chlorine concentration of the electrolyzed seawater in the fish holding tank was reduced by the addition of ice and by covering with a thermal insulating sheet. However, the chlorine concentration decreased when fish were put into the fish holding tank. In a fisher-boat tank, viable bacterial count remained less than 100 CFU/mL for at least 60 minutes when ice was present. It was also shown that electrolyzed seawater was useful for disinfection of deck or fishing equipment.