Efectividad del agua electrolizada oxidadora (EO) en la inactivación de Listeria monocytogenes en lechuga ( Lactuca sativa L.)

The effectiveness of electrolyzed oxidizing water for inactivating L. monocytogenes in suspension and inoculated in lettuce was evaluated. An electrolytic cell for the production of EO water was built and a solution of 5% NaCl was used. The EO water produced had a residual chlorine concentration of 29 parts per million (ppm) and pH 2.83. Ten strains of L. monocytogenes isolated from processed chicken (109 CFU/ml) were inoculated on 9 ml of EO water or 9 ml of deionized water (control) and incubated at 15°C for 5, 10, 15 and 20 min. The surviving population of each strain was determined on Columbia agar. An exposure time of 5 min reduced the populations by approximately 6.6 log CFU/ml. The most resistant strains to hypochlorite (NaOCl) were selected and used in a strain mixture (9.56 log CFU/ml, 109UFC/ml approximately) for the inoculation of 35 lettuces by the dip