Efficacy of Slightly Acidic Electrolyzed Water and UV-Ozonated Water Combination for InactivatingEscherichia ColiO157:H7 on Romaine and Iceberg Lettuce during Spray Washing Process

2016 ◽  
Vol 81 (7) ◽  
pp. M1743-M1748 ◽  
Author(s):  
Yu-Hsin Pang ◽  
Yen-Con Hung
Keyword(s):  
Electrolyzed Water ◽  
Iceberg Lettuce ◽  
Washing Process ◽  
Ozonated Water

Effect of Ozonated Water Treatment on Microbial Control and on Browning of Iceberg Lettuce (Lactuca sativa L.)

2006 ◽  
Vol 69 (1) ◽  
pp. 154-160 ◽  
Author(s):  
SHIGENOBU KOSEKI ◽  
SEIICHIRO ISOBE
Keyword(s):  
Water Treatment ◽  
Lactuca Sativa ◽  
Combined Treatment ◽  
Microbial Control ◽  
Hot Water ◽  
Pal Activity ◽  
Iceberg Lettuce ◽  
A Value ◽  
Lactuca Sativa L ◽  
Ozonated Water

We examined the effect of ozonated water treatment on microbial control and quality of cut iceberg lettuce (Lactuca sativa L.). Fresh-cut lettuce was washed in ozonated water (3, 5, and 10 ppm) for 5 min at ambient temperature. The native bacterial population on the lettuce declined in response to a rise in ozone concentration. However, there was no further bacterial reduction (1.4 log CFU/g) above 5 ppm ozone. Although ozonated water treatment increased the phenylalanine ammonia lyase (PAL) activity of the lettuce stored at 10°C compared with the water wash treatment after 1 day of storage, the concentration of ozone did not affect PAL activity. The a* value of the residue of the lettuce methanol extracts, which reflects the extent of browning, increased dramatically in lettuce treated with 10 ppm ozonated water compared with other treatments. Treatment with 3 or 5 ppm ozonated water resulted in more rapid changes in the a* value than after the water treatment. The combined treatment of hot water (50°C, 2.5 min) followed by ozonated water (5 ppm, 2.5 min) had the same bactericidal effect as treatment with ozonated water (5 ppm, 5 min) or sodium hypochlorite (NaOCl, 200 ppm, 5 min), giving a reduction in bacteria numbers of 1.2 to 1.4 log CFU/g. The ascorbic acid content of the lettuce was not affected by these treatments. The combined treatment of hot water followed by ozonated water greatly inhibited PAL activity for up to 3 days of storage at 10°C. Treatment with this combination greatly suppressed increases in the a* value, thus retarding the progress of browning compared with other treatments throughout the 6-day storage. NaOCl treatment also inhibited browning for up to 3 days of storage. Bacterial populations on the lettuce treated with sanitizers were initially reduced but then showed rapid growth compared with that of the water wash treatment, which did not reduce bacterial counts initially.

scholarly journals The Chlorine Reduction in Edamame by Water-Ozonated Minimally Process

2021 ◽  
Vol 1 (3) ◽  
Author(s):  
Silvia Oktavia Nur Yudiastuti ◽  
Rizza Wijaya
Keyword(s):  
Contact Time ◽  
Research Method ◽  
Residual Chlorine ◽  
Titration Method ◽  
Research Results ◽  
Washing Process ◽  
Ozonation Time ◽  
Water Based ◽  
Washing Water ◽  
Ozonated Water

The objective of this article was to study the effect of washing edamame using ozonated water to reduce residual chlorine contained in edamame through a continuous washing process. Chlorine residue in edamame was caused by the use of fertilizers and pesticides that contain chlorine compounds. The research method used was descriptive explanatory research consist of two treatment levels of ozonation time (0, 10, and 15 minutes) and ozone contact time (0, 12, 18, and 24 minutes) which were repeated twice. The residual chlorine and pesticide concentrations were calculated using the titration method. Based on research results, ozone can reduce chlorine in edamame. The lowest detected chlorine was in edamame which had been washed using ozone water with an ozonation time of 15 minutes with the amount of chlorine reduced by 56%. The longer the contact time, the greater the amount of reduced chlorine and the lower the concentration of ozone remaining in the washing water. Based on the research results, a brief conclusion that can be explained was ozone could reduce chlorine in edamame caused by fertilizer and disinfectant overuse until 50%.

Reduction of Escherichia coli O157:H7 on Produce by Use of Electrolyzed Water under Simulated Food Service Operation Conditions

2009 ◽  
Vol 72 (9) ◽  
pp. 1854-1861 ◽  
Author(s):  
PHILIPUS PANGLOLI ◽  
YEN-CON HUNG ◽  
LARRY R. BEUCHAT ◽  
C. HAROLD KING ◽  
ZHI-HUI ZHAO
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Fruits And Vegetables ◽  
Tap Water ◽  
Food Service ◽  
Escherichia Coli O157 ◽  
Electrolyzed Water ◽  
E Coli ◽  
Operation Conditions ◽  
Iceberg Lettuce

Treatment of fresh fruits and vegetables with electrolyzed water (EW) has been shown to kill or reduce foodborne pathogens. We evaluated the efficacy of EW in killing Escherichia coli O157:H7 on iceberg lettuce, cabbage, lemons, and tomatoes by using washing and/or chilling treatments simulating those followed in some food service kitchens. Greatest reduction levels on lettuce were achieved by sequentially washing with 14-A (amperage) acidic EW (AcEW) for 15 or 30 s followed by chilling in 16-A AcEW for 15 min. This procedure reduced the pathogen by 2.8 and 3.0 log CFU per leaf, respectively, whereas washing and chilling with tap water reduced the pathogen by 1.9 and 2.4 log CFU per leaf. Washing cabbage leaves for 15 or 30 s with tap water or 14-A AcEW reduced the pathogen by 2.0 and 3.0 log CFU per leaf and 2.5 to 3.0 log CFU per leaf, respectively. The pathogen was reduced by 4.7 log CFU per lemon by washing with 14-A AcEW and 4.1 and 4.5 log CFU per lemon by washing with tap water for 15 or 30 s. A reduction of 5.3 log CFU per lemon was achieved by washing with 14-A alkaline EW for 15 s prior to washing with 14-A AcEW for 15 s. Washing tomatoes with tap water or 14-A AcEW for 15 s reduced the pathogen by 6.4 and 7.9 log CFU per tomato, respectively. Application of AcEW using procedures mimicking food service operations should help minimize cross-contamination and reduce the risk of E. coli O157:H7 being present on produce at the time of consumption.

Decontamination of Lettuce Using Acidic Electrolyzed Water

2001 ◽  
Vol 64 (5) ◽  
pp. 652-658 ◽  
Author(s):  
SHIGENOBU KOSEKI ◽  
KYOICHIRO YOSHIDA ◽  
SEIICHIRO ISOBE ◽  
KAZUHIKO ITOH
Keyword(s):  
Reduction Potential ◽  
Effective Means ◽  
Cellular Tissue ◽  
Coliform Bacteria ◽  
Aerobic Bacteria ◽  
Electrolyzed Water ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Alkaline Electrolyzed Water ◽  
Ozonated Water

The disinfectant effect of acidic electrolyzed water (AcEW), ozonated water, and sodium hypochlorite (NaOCl) solution on lettuce was examined. AcEW (pH 2.6; oxidation reduction potential, 1140 mV; 30 ppm of available chlorine) and NaOCl solution (150 ppm of available chlorine) reduced viable aerobes in lettuce by 2 log CFU/g within 10 min. For lettuce washed in alkaline electrolyzed water (AlEW) for 1 min and then disinfected in AcEW for 1 min, viable aerobes were reduced by 2 log CFU/g. On the other hand, ozonated water containing 5 ppm of ozone reduced viable aerobes in lettuce 1.5 log CFU/g within 10 min. It was discovered that AcEW showed a higher disinfectant effect than did ozonated water significantly at P < 0.05. It was confirmed by swabbing test that AcEW, ozonated water, and NaOCl solution removed aerobic bacteria, coliform bacteria, molds, and yeasts on the surface of lettuce. Therefore, residual microorganisms after the decontamination of lettuce were either in the inside of the cellular tissue, such as the stomata, or making biofilm on the surface of lettuce. Biofilms were observed by a scanning electron microscope on the surface of the lettuce treated with AcEW. Moreover, it was shown that the spores of bacteria on the surface were not removed by any treatment in this study. However, it was also observed that the surface structure of lettuce was not damaged by any treatment in this study. Thus, the use of AcEW for decontamination of fresh lettuce was suggested to be an effective means of controlling microorganisms.

Effect of Alfalfa Seed Washing on the Organic Carbon Concentration in Chlorinated and Ozonated Water†

2004 ◽  
Vol 67 (4) ◽  
pp. 813-817 ◽  
Author(s):  
KATHLEEN T. RAJKOWSKI ◽  
EUGENE W. RICE
Keyword(s):  
Organic Carbon ◽  
Tap Water ◽  
Oxygen Demand ◽  
Nutrient Sources ◽  
Assimilable Organic Carbon ◽  
Organic Carbon Concentration ◽  
Generation Times ◽  
Washing Process ◽  
Alfalfa Seed ◽  
Ozonated Water

The bioassays assimilable organic carbon (AOC) and coliform growth response are better indexes than biological oxygen demand to determine water quality and water's ability to support the growth of bacteria. Ozonated (5 mg/liter) and chlorinated tap water were used to wash alfalfa seeds for 30 min. After washing in the ozonated tap water, the AOC concentration increased 25-fold, whereas the dissolved ozone decreased to undetectable levels. The AOC levels for the chlorinated water after washing the seeds also increased. These increases are due to ozone's strong oxidizing ability to break down refractory, large-molecular-weightcompounds, forming smaller ones, which are readily used as nutrient sources for microorganisms. This same phenomenon was observed when using ozone in the treatment of drinking water. The AOC value increased from 1,176 to 1,758 μgC-eq/liter after the reconditioned wastewater was ozonated. When the ozonated wastewater was inoculated with Salmonella serotypes, the cells survived and increased generation times were observed. The increased nutrients would now become more readily available to any pathogenic microorganisms located on alfalfa seed surface as seen with the increase in the inoculated levels of Salmonella in the ozonated wastewater. If the washing process using ozonated water is not followed by the recommended hypochlorite treatment or continually purged with ozone, pathogen growth is still possible.

scholarly journals Inactivation Activities of Ozonated Water, Slightly Acidic Electrolyzed Water and Ethanol against SARS-CoV-2

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5465
Author(s):  
Yohei Takeda ◽  
Dulamjav Jamsransuren ◽  
Yoshimasa Makita ◽  
Akihiro Kaneko ◽  
Sachiko Matsuda ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Viral Genome ◽  
Test Solution ◽  
Spike Protein ◽  
Control Group ◽  
Virucidal Activity ◽  
Electrolyzed Water ◽  
Fetal Bovine ◽  
Pcr Targeting ◽  
Ozonated Water

This study aimed to compare the SARS-CoV-2-inactivation activity and virucidal mechanisms of ozonated water (OW) with those of slightly acidic electrolyzed water (SAEW) and 70% ethanol (EtOH). SARS-CoV-2-inactivation activity was evaluated in a virus solution containing 1%, 20% or 40% fetal bovine serum (FBS) with OW, SAEW or EtOH at a virus-to-test solution ratio of 1:9, 1:19 or 1:99 for a reaction time of 20 s. EtOH showed the strongest virucidal activity, followed by SAEW and OW. Even though EtOH potently inactivated the virus despite the 40% FBS concentration, virus inactivation by OW and SAEW decreased in proportion to the increase in FBS concentration. Nevertheless, OW and SAEW showed potent virucidal activity with 40% FBS at a virus-to-test solution ratio of 1:99. Real-time PCR targeting the viral genome revealed that cycle threshold values in the OW and SAEW groups were significantly higher than those in the control group, suggesting that OW and SAEW disrupted the viral genome. Western blotting analysis targeting the recombinant viral spike protein S1 subunit showed a change in the specific band into a ladder upon treatment with OW and SAEW. OW and SAEW may cause conformational changes in the S1 subunit of the SARS-CoV-2 spike protein.

Control of Brettanomyces bruxellensis on wine grapes by post-harvest treatments with electrolyzed water, ozonated water and gaseous ozone

2018 ◽  
Vol 47 ◽  
pp. 309-316 ◽  
Author(s):  
Francesco Cravero ◽  
Vasileios Englezos ◽  
Kalliopi Rantsiou ◽  
Fabrizio Torchio ◽  
Simone Giacosa ◽  
...  
Keyword(s):  
Wine Grapes ◽  
Brettanomyces Bruxellensis ◽  
Electrolyzed Water ◽  
Post Harvest ◽  
Gaseous Ozone ◽  
Ozonated Water
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