Recent advances to control spoilage microorganisms in washing water of fruits and vegetables: the use of electrolyzed water

Washing water used for processing fruits and vegetables can convey spoilage fungi and bacteria. The common procedure to reduce microbial contamination involves the use of chlorine based compounds. Recently, electrolyzed water (EW) has been evaluated as an alternative measure in controlling microbial spoilage contamination occurring during washing steps. This work reviews results related to the application of EW for controlling microbial viability responsible for decay development during storage period. EW produced with sodium bicarbonate as electrolyte reduced Penicillium spp. population in water and, consequently, green mould decay in citrus fruits; the use of sodium chloride in EW production inactivated spores of Fusarium sp. in water and reduced pineapple decay during storage at 12 degrees C for 20 days as well as controlled yeast and mould population in date fruit up to six months of cold storage. EW was also found effective in controlling spoilage bacteria on ready-to-eat produce. Pseudomonas fluorescens, Pan toea agglomerans, and Rhanella aquatilis were undetectable in electrolyzed process water amended with sodium chloride although similar treatment slightly reduced Erwinia carotovora load inoculated onto lettuce. EW at low free chlorine concentration reduced viability of Pseudomonas spp. and psychrotrophic bacteria in both simulated and industrial washing water. EW treatment of fresh cut lettuce dipped in microbial contaminated water reduced Pseudomonas spp. of about 1 log cfu g(-1) delaying spoilage symptoms that occurred early in untreated vegetables. These results demonstrate that the use of EW can control spoilage microorganisms in washing water, reduce cross contamination phenomena and delay fruit and vegetable decay.