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The food industry has recognized electrolyzed oxidizing water (EOW) as a promising alternative decontamination technique. However, there is not a consensus about the sanitizing mechanism of EOW. In this study, we evaluated the disinfection efficacy of different types of EOW on Escherichia coli. Based on the hypothesis of hydroxyl radicals existing in EOW, in the present study, the hydroxyl radicals existed in slightly acidic electrolyzed water (SAEW) and acidic electrolyzed water (AEW) diluted to different levels were detected quantitatively. An ultraviolet (UV) spectrophotometer was used to scan EOW with different pH values. Accounting for the results of UV scanning to EOW with different pH value and the disinfection efficacy of different types of EOW, it can be concluded that considering the lower chlorine concentration of EOW compared with traditional chlorine disinfectants, the existing form of chlorine compounds rather than the hydroxyl radicals played important role in the disinfection efficacy of EOW., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The disinfection efficacy of acidic electrolyzed water including slightly acidic electrolyzed water (SAEW) and strongly acidic electrolyzed water (AEW) on the fresh-cut lotus roots and their effects on the appearance quality of fresh-cut lotus root were evaluated in the present paper. The results showed that SAEW treatment could reduce the natural microbial flora populations as well as the inoculated populations of fresh-cut lotus roots significantly. Also, our results obtained from the present study suggested that SAEW treatment could maintain the appearance quality and market values more effectively than acidic electrolyzed water (AEW) treatment. Considering that SAEW is environmentally friendly and has dual efficacy of disinfection and browning-prevention, it may be a better choice in the processing of fresh-cut lotus roots. The results implied that SAEW could inhibit the polyphenol oxidase (PPO) activity, thus keep the overall visual quality. However, how SAEW treatments affect PPO activity of the fresh-cut lotus roots is still unknown and further research is needed. Practical applications How to prevent the quality deterioration of fresh-cut lotus root, which limited its safety and processing, had become a serious problem. In the past, the strong disinfection efficacy of acidic electrolyzed water (AEW) and its application in food industry including the disinfection of fruits and vegetables were widely reported. Due to its neutral pH and lower available chlorine concentration (10-30 mg/L), slightly acidic electrolyzed water (SAEW) showed a promising prospect in the agriculture and food industry. In the present study, the disinfection efficacy of SAEW on the fresh-cut lotus roots was investigated. Moreover, the effect of SAEW treatment on the appearance quality of fresh-cut lotus root was evaluated. This study confirmed that SAEW treatment might have a high potential for practical use in the processing fresh-cut lotus roots processing. [ABSTRACT FROM AUTHOR]

Leafy vegetables are the major source of nitrite intake in the human diet, and technological processing to control the nitrite levels is necessary to the harvested vegetables destined for consumption. In this work, the effect of aqueous chlorine dioxide (ClO2) treatment on the nitrite levels in fresh lettuces during storage was studied. The results showed the appropriate aqueous ClO2 solutions treatment (30 and 45 mg L-1, 10 min) could reduce the nitrite levels or retard the peak occurrence in fresh lettuces during storage. The reduction of nitrite levels in fresh lettuces with appropriate ClO2 treatment can be attributed to two aspects including the inactivation of nitrate reductase directly and the reduction of the bacterial populations. This study will provide a useful method to reduce the nitrite levels in fresh lettuces destined for short storage followed by consumption. [ABSTRACT FROM AUTHOR]

The accumulation of γ-aminobutyric acid and the microbial decontamination are concerned increasingly in the production of sprouts. In this work, the effect of the treatment by slightly acidic electrolyzed water on the accumulation of γ-aminobutyric acid in the germinated brown millet was evaluated by high performance liquid chromatography during germination. The results showed that slightly acidic electrolyzed water with appropriate available chlorine (15 or 30 mg/L) could promote the accumulation of γ-aminobutyric acid by up to 21% ( P < 0.05). However, the treatment with slightly acidic electrolyzed water could not enhance the sprouts growth of the germinated brown millet. The catalase and peroxidase activities of the germinated brown millet during germination were in agreement with the sprouts growth. Our results suggested that the accumulation of γ-aminobutyric acid was independent of the length of sprouts in germinated grains. Moreover, the treatment with slightly acidic electrolyzed water significantly reduced the microbial counts in the germinated millet ( P < 0.05) and the treatment with high available chlorine concentration (15 and 30 mg/L) showed stronger anti-infection potential in the germinated brown millet than that of lower available chlorine concentration (5 mg/L). In conclusion, the treatment with slightly acidic electrolyzed water is an available approach to improve the accumulation of γ-aminobutyric acid and anti-infection potential in the germinated brown millet, and it can avoid too long millet sprouts. [ABSTRACT FROM AUTHOR]

In the present study, the disinfection efficacy on fresh-cut cilantro of the combination of strongly acidic electrolyzed water (AcEW) and alkaline electrolyzed water (AlEW) was evaluated, in comparison with single slightly acidic electrolyzed water (SAEW) and single AcEW treatments. The populations of E. Coli O78 on inoculated cilantro treated by AlEW 5 min + AcEW 5 min, was not detected while 3.43 and 3.73 log 10 CFU/g in the AlEW 2.5 min + AcEW 2.5 min and AcEW 2 min + AlEW 2 min + AcEW 2 min treatments respectively. Our results implied that the bactericidal abilities of the combination of AlEW and AcEW treatments were higher than that of single AcEW and SAEW, which also was demonstrated microscopically by scanning electron microscopy (SEM). Moreover, the efficacy of combination of AcEW and AlEW in reducing natural micro flora on fresh-cut cilantro was also evaluated compared with single AcEW and SAEW. The results showed that the combination of AlEW and AcEW had stronger sterilization ability than single AcEW and SAEW. Considering the utilizations of AlEW and disinfection efficacy, we suggest that the combination of AlEW and AcEW may also be a better choice in fresh-cut produce. [ABSTRACT FROM AUTHOR]