Investigating the use of different methods of lettuce washing in Shigella Flexneri microbial load

One of the problems with the consumption of fresh vegetables is the possibility of contamination with pathogenic bacteria. Washing fresh vegetables plays an important role in reducing the microbial population and increasing the safety of these products. Electrolyzed water has been considered as a new disinfectant in recent years. It is antiseptic, inexpensive and safe that affects different species of bacteria, fungi and viruses. In this study, the use of various types of washing water has been studied on the reduction of Shigella Flexneri population in lettuce. Types of water used include drinking water, acidified drinking water, chlorinated deionized water with chlorine concentrations of 50 and 25 mg / L, neutralized electrolyzed water, acidified electrolyzed water with a chlorine concentration of 50 and 25 mg / L were studied at different washing times (60 and 180 seconds) and different washing temperatures (4 and 25 °C). The results of this study showed that electrolysis of water had the most efficiency in reducing the microbial load of lettuce (72%) and the acidification of electrolyzed water increased its disinfection efficiency (75%). In addition, the study of lettuce microbial population during 1 to 4 days showed that the growth rate of microbial growth in lettuce samples was slower than other washing methods.