• Food Science and Preservation
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• v.11 no.4
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• pp.530-537
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• 2004

This study was conducted to determine the inactivation effect of electrolyzed water and organic acids either alone or in combination on L. monocytogenes or natural microflora on lettuce. Acidic electrolyzed water completely inactivated L. monocytogenes in broth system within 60 sec, but alkalin electrolyzed water caused approximate 1.7 log CFU/g reduction. However, acidic electrolyzed water reduced only 2.5 log CFU/g of L. monocytogenes on lettuce, and similar antimicrobial effect was observed with alkalin electrolyzed water. In the meantime, acidic and alkaline electrolyzed water caused approximately 2 log CFU/g reduction compared to control, whereas both electrolyzed water combined with $1\%$ organic acids ranged from 2.6 to 3.7 log CFU/g reduction. Among the organic acids, both electrolyzed water combined with $1\%$ citric acid showed the strongest synergistic antimicrobial effect to reduce L. monocytogenes on lettuce as well as total counts, yeast and molds. When antimicrobials, alone or in combination were treated into L. monocytogenes inoculated lettuce at $5^{\circ}C\;and\;15^{\circ}C$ for designed periods, the combined alkalin electrolyzed water with $1\%$ citric acid showed the greatest potential to inhibit growth of the bacteria. According to Scanning Electron Microscopy(SEM), the treatment of electrolyzed alkali water in combination with $1\%$ citric acid highly reduced the growth of the L. monocytogenes compared to single treatment and resulted in causing the destruction of cell membrane.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1511-1517
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• 1999

Effects of washing methods using electrolyzed acid water on lettuce(Lactuca sativa) and quality changes during storage were investigated. The multi-stage immersion treated 3 times in 2 min showed more effective than others to remove microorganisms. Total count of lettuce after immersion in electrolyzed acid water was decreased to 1/100-1/300 of $5.8\;{\times}\;l0^5CFU/g$ of non-immersed lettuce and $2.3\;{\times}\;l0^5CFU/g$ of tap water immersed lettuce. Also coliforms was significantly decreased to 1/3,000 of $3.1\;{\times}\;10^3CFU/g$ after electrolyzed acid water washing. However, microbial levels of electrolyzed acid water treated one became to be similar to those of non-treated lettuce after 3 days of storage at $10^{\circ}C$. The color values of L and b of lettuce treated with electrolyzed acid water were somewhat higher than those of others. Though chlorophyll content of lettuce just after immersion in electrolyzed acid water was 9% lower than those of non-treated one, the content was decreased to the same level of other treatments during storage. Decaying ratio showed the lowest value in lettuce immersed in electrolyzed acid water until 6 days of storage. The sensory tests for overall acceptability and appearance of lettuce immersed in electrolyzed acid water showed higher than those of others until $3{\sim}6$ days of storage.

• Food Science and Preservation
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• v.6 no.4
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• pp.417-423
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• 1999

Quality changes of crown daisy and kale were investigated during storage at 10$^{\circ}C$ after washing with cooled electrolyzed acid water at 3 times in 2 min. Total count and coliform count of crown daisy and kale after immersion in electrolyzed acid water were decreased to 1/130 and 1/1,170 of non-immersed crown daisy and to l/870 and l/470 of non-immersed kale. However total count and coliform count were increased to the similar levels of non-immesed and tap water immersed one after 6 days of storage. Weight loss of crown daisy and ka1e were lower than others for 3 days of storage but higher than that of one after that time. Decay rate of crown daisy and kale immersed electrolyzed acid water showed lower than that of non-immersed and tap water immersed one for 6 days. In case of kale, rupture strength was higher than others at just after immersion and showed similar values after initial storage period. Color value of both crown daisy and kale showed high L, b and low a value in the order of electrolyzed acid water, tap water and non-treatment. Chlorophyll content of crown daisy and kale were lower than those of others just after immersion in electrolyzed acid water, but showed rapid reduction in the order of non-treatment. tap water and electrolyzed acid water after 6 days. Overall organoleptic properties of crown daisy and kale in immersion electrolyzed acid water were higher than those of others.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1045-1051
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• 1996

The influence of electrolyzed acid-water (oxidation-reduction potential (ORP): above 1,150 mV, pH : 2.5) on the survival of some microorganisms was investigated. It was observed that the ORP of electrolyzed acid-water was kept at the level of above 1,000 mV for 15 days at room temperature. Escherichia coli. Salmonella typhi, Staphylococcus aureus and Saccharomyces cerevisiae were not detected after 10 to 40 min in electrolyzed acid-water. However, Bacillus cereus showed higher tolerance to electrolyzed acid-water than other test microorganisms. After 60 min of inoculation, only 0.4% of initial population remained. The investigation of surface sterilization effect on some vegetables was carried out too. Total count of cabbage, Chinese cabbage and kale were reduced to below 3% of initial count, and no coliform was detected after 20 to 60 min of immersion in 5 volumes of electrolyzed acid-water. In the lettuce, total and coliform counts were reduced to 90% and 2% of initial population. This study shows that the electrolyzed acid-water has a potential for the sterilization of food products such as vegetables and fruits which cannot be thermally sterilized.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.188-194
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• 2010

The electrolyzed sterilizing water is useful functional aqueous solution, which is produced by electrolyzing aqueous solution. Electrolytic supplement such as salt or hydrochloric acid is added into tap water. Electrolyzed sterilizing water is classified as three types; strongly acidic electrolyzed water, weakly acidic electrolyzed water, and sodium hypochlorite water. In this study, preparation principles, advantages, and disadvantages of electrolyzed sterilizing water were analyzed. The technology trend in electrolyzed sterilizing water was analyzed based on patent application year, countries, main applicants, and each technologies.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.365-367
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• 2004

Electrolyzed-acid water was used to prolong shelf life of salted Chinese cabbage during storage, Chinese cabbage was salted, washed twice with electrolyzed-acid water, packaged in high-density polyethylene film, and stored at $10^{\circ}C$. Titratable acidity, pH, color, and microbial loads of salted Chinese cabbage were measured. Treated sample showed lower pH, total microbial count, and lactic acid bacteria than those of control, whereas almost equal titratable acidity and color, Acidity of treated sample maintained lower pH value until 6 days, and remained constant thereafter, Sharp decrease in L value occured after 2 days for control, and was delayed 4-6 days for treated sample. Salted Chinese cabbage treated with electrolyzed-acid water showed lower total microbial load ($10^3\;CFU/mL$) and lactic acid bacteria ($10^1\;CFU/mL$) after washing, whereas similar loads, compared to control after 6 days. Treatment with electrolyzed-acid water maintained higher quality for salted Chinese cabbage, with limited shelf life extension.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.545-549
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• 1998

This study was carried out to improve the storage stability of export peeled-chestnuts using electrolyzed acid-water, because ice-cold tap water generally used to store export peeled-chestnuts grew turbid during the cold chain, decreasing the quality. The changes of pH and turbidity in the electrolyzed water used for storing peeled-chestnuts were investigated. The pH value rapidly changed when stored at $30^{\circ}C$, whereas it very slowly changed at $4^{\circ}C$. This was especially evident by the change in pH from 2.5 to 3.4 of the electrolyzed acid-water after 8 days. In the case of turbidity, closely correlated with the pH change, the electrolyzed water used for storing peeled-chestnuts was very turbid when stored at $30^{\circ}C$, but it was not even until 14 days at $4^{\circ}C$, as evident by the absorbance $(OD_{660})$ of electrolyzed acid-water at pH 2.5 and $4^{\circ}C$ being only 0.01 after 14 days and 0.11 after 35 days. Sensory evaluation, tested by expert panel, of the chestnuts stored in electrolyzed water was not significantly different compared to the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.761-767
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• 1996

To lessen the initial level of microorganisms, electrolyzed acid-water was used as washing and brine water in the manufacturing process. On the washing and salting processes, application of electrolyzed acid-water showed a possibility to lessen the microorganism level of Chinese cabbage effectively. Microbial level of Chinese cabbage was reduced to about 1/4 level by salting and washing process with electrolyzed acid-water while Chinese cabbage salted with tap water increased to about 1.7 times. And no coliform and E. coli were detected. However significant differences between seasoning mixtures prepared with electrolyzed acid-water and with tap water were not observed in microbial levels. Relatively low level of total count in kimchi prepared with electroyzed acid-water was kept until 15 days of fermentation at $10^{\circ}C.$ Any significant difference between them was not observed after 20 days of fermentation. pH and acidity were showed the same tendencies as microbial count.

• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.318-320
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• 2005

Antioxidation effect of reduced electrolyzed water, which has been known as antiaging agent has been investigated with very simple method. Antioxidation effect of the reaction of linoleic acid with oxygen has been measured and analyzed. Alkaline reduced electrolyzed waters are better effect, rather acidic oxidized electrolyzed waters accelerates oxidation reaction.

• Food Science and Preservation
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• v.9 no.2
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• pp.240-247
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• 2002

This study, to enhance the sterilization, browning inhibition and precooling effect of electrolyzed oxidizing water(EOW) as cleaning water on food industry, was carried out to investigate the efficacy of electrolyzed oxidizing water(EOW) with 0.85% NaCl, 0.5% ethanol, polysorbate 80 of 1 ppm, 0.5% lemon juice and 0.5% citron juice. Escherichia coli KCTC 1039 with initial count of 5.63$\times$10$\^$8/ CFU/mL were reduced to <10$^1$CFU/mL after 15∼30 sec when it was treated by electrolyzed oxidizing water added with various food additives. Bacillus cereus KCTC 1012 were reduced to <10$^1$ CFU/mL after 2 minutes treatment with electrolyzed oxidizing water containing polysorbate 80 and ethanol. Iactobacillus plantarum KCTC 3108 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80, citron juice and lemon juice, respectively. Erwinia carotovora subsp. carotovora KCTC 2776 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80 and lemon juice. Browning inhibition effect was determined by comparison of polyphenol oxidase activity. Inhibition ratio of polyphenol oxidase was approximately 62∼84% in most treatments with the exception of 57% and 25% inhibition by 0.5% ascorbic acid and polysorbate 80, respectively. Sliced potato dipped in electrolyzed oxidizing water containing NaCl and citron juice for 30 minutes showed significantly low PPO activity, 64 units in treatment with NaCl and 91 units in treatment with citron juice. At the same time, changes in color value(△E) of sliced potato was below 3 in most treatments.