Pathogen reduction and quality of lettuce treated with electrolyzed oxidizing and acidified chlorinated water

The efficacy of electrolyzed oxidizing (EO) and acidified chlorinated water (45 ppm residual chlorine) was evaluated in killing Escherichia coli O157:H7 and Listeria monocytogenes on lettuce. After surface inoculation, each leaf was immersed in 1.5 L of EO or acidified chlorinated water for 1 or 3 min at 22 degreesC. Compared to a water wash only, the EO water washes significantly decreased mean populations of E. coli O157:H7 and L. monocytogenes by 2.41 and 2.65 log(10) CFU per lettuce leaf for 3 min treatments, respectively (p less than or equal to 0.05). However, the difference between the bactericidal activity of EO and acidified chlorinated waters was not significant (p greater than or equal to 0.05). Change in the quality of lettuce subjected to the different wash treatments was not significant at the end of 2 wk of storage.