• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.526-533
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• 2006

This study was carried out to investigate the efficacy of strong acidic electrolyzed acid water (SAEW; Strong acidic electrolyzed water, pH 2.76, ORP 1,128 mV, HClO 105.0 ppm) and low alkaline electrolyzed water (LAEW; Low alkaline electrolyzed water, pH 8.56, ORP 660 mV, HClO 73.8 ppm) as storing liquid for peeled lotus root. During storage at $5^{\circ}C$, it was showed that SAEW and LAEW inhibit growth of microorganisms until at least 5 days of storage. Total phenolic contents, polyphenol oxidase (PPO) activity, and color differences value $({\Delta}E)$ of peeled lotus roots stored in SAEW and LAEW were lower than that of one stored in TW (tap water). The hardness decrement of lotus roots stored in SAEW and LAEW were lower than that of lotus root stored in TW too. Contents of moisture crude protein crude fat, crude ash, crude fiber, and total sugars were gradually decreased during storage. Whereas vitamin C content of lotus root stored in 0.6% acetic acid was most rapidly decreased to 25% as compared with one of initial days of storage that of lotus roots stored in SAEW and LAEW was not decreased significantly as compared with one stored in TW. Sensory characteristic during storage was preferable on lotus root stored in SAEW to the other treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1830-1841
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• 2012

We investigated the changes in microbial and physicochemical characteristics of the raw materials of Saengsk (brown rice, barley, carrot, potato, Angelica utilis Makino and kale) during storage after treatment with slightly acidic electrolyzed water (SAEW). To confirm the antimicrobial effects of the treatment washing solutions as well as the physicochemical changes in chromaticity, we stored the raw materials of Saengsik for 5, 10, 15, 20, 25 and 30 days at storage temperatures of 4, 10, 15, 20, 25 and $30^{\circ}C$ in a shelf-life study. The effects of microbial inhibition were higher in carrot treated with SAEW than in that treated with NaOCl, as indicated by a 1.75 log CFU/g reduction. Moreover, a 1.54 log CFU/g reduction of total coliforms was achieved in brown rice in response to SAEW treatment, which was higher than NaOCl treatment at all storage temperatures and periods. The lightness, redness and yellowness values of the raw materials of Saengsik were not significantly affected by SAEW treatments, except for Angelica utilis Makino and kale, whereas SAEW treatment resulted in decreased chromaticity values when compared to the NaOCl treatment. Overall, there was a significant difference (p<0.05) between the efficacy of the SAEW and NaOCl treatments. These results indicate that washing with SAEW is an effective method to reduce the microorganisms and enhance the shelf-life of raw materials of Saengsik; therefore, it can be effectively used to sanitize ingredients of Saengik without affecting the other properties during storage.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1502-1509
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• 2015

The objectives of this study were to evaluate the effect of combined treatments (slightly acidic electrolyzed water (SAEW), ultrasound (US), or mild heat (60℃)) on the growth of Listeria monocytogenes and Salmonella enterica serovar Typhimurium in fresh-cut bell pepper, and the shelf-life and sensory quality (color and texture) were followed during storage at 4℃ and 25℃. An additional 0.65, 1.72, and 2.70 log CFU/g reduction was achieved by heat treatments at 60℃ for 1 min for DW, SAEW, and SAEW+US, respectively. Regardless of the type of pathogen, the combined treatment (SAEW+US+60℃) achieved a significantly (p < 0.05) longer lag time in all treatment groups. This combined treatment also prolonged the shelf-life of bell pepper up to 8 days and 30 h for the storage at 4℃ and 25℃, respectively. There was also no significant difference in the color and hardness of treated (SAEW+US+60℃) bell pepper from that of control during the storage. This new hurdle approach is thus expected to improve the microbial safety of bell peppers during storage and distribution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.586-592
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• 2011

The storage quality of soybean sprouts washed with various electrolyzed waters was investigated. The washing solutions consisted of tap water (TW), sodium hypochlorite electrolyzed water (SHEW), and slightly acidic electrolyzed water (SAEW). The number of bacteria on the soybean sprouts after 5 min of exposure to TW, SHEW, and SAEW resulted in >0.5, 2.0, and 2.0 log CFU/g reductions, respectively. At both $4^{\circ}C$ and $25^{\circ}C$, the number of bacteria, weight loss ratio, and b value rapidly increased, and pH and L value rapidly decreased in soybean sprouts washed with TW. Whereas, the number of bacteria, pH, weight loss ratio, and color slowly changed in the soybean sprouts washed with SHEW and SAEW. Consequently, these results indicate that washing with electrolyzed water is an effective means of maintaining the quality and enhancing the shelf-life of soybean sprouts; both SHEW and SAEW reduced bacterial growth without affecting the other properties of soybean sprouts during storage.

• Food Science and Preservation
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• v.14 no.1
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• pp.8-17
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• 2007

The efficacy of strong acidic electrolyzed water (SAEW) at pH 2.53, with ORP of 1,088 mV and HClO concentration of 91.25 ppm, and low alkaline electrolyzed water (LAEW) at pH 8.756, with ORP of 534 mV and HClO concentration of 105.70 ppm, as storing liquids for peeled potato and sweet potato was evaluated in this study. During storage at $5^{\circ}C$, total phenolic contents and PPO activities of peeled potato and sweet potato stored in SAEW and LAEW were lower than those of control samples stored in tap racer (TW) with 0.85% (w/v) NaCl and 0.5% (w/v) sodium metabisulfite (SMS). Increment in color differences and decreases in hardness of peeled potato and sweet potato stored in SAEW and LAEW were lower than those of controls. Also, SAEW and LAEW inhibited growth of microorganisms for at least 3-6 days of storage. The sensory characteristics of peeled potato and sweet potato stored in LAEW were best during the first half of the storage period, compared to samples preserved by other methods.

• Journal of Mushroom
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• v.20 no.2
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• pp.78-85
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• 2022

The consumption of Flammulina velutipes mushroom imported from Korea has been associated with the cases of listeriosis in the United States, Canada, and Australia. We investigated the effect of sanitizing the plastic wrapper (used in packaging F. velutipes) with slightly acidic electrolyzed water (SAEW) and ultraviolet C waterproof light-emitting diode (UVC-W-LED) on reducing the Listeria monocytogenes. Further, the effect of UVC-LED on L. monocytogenes growth in F. velutipes at different storage temperatures (2, 4, and 10℃) was determined. The combined (SAEW+UVC-W-LED) treatment for 5-10 min reduced 99.9% of bacterial population from the contaminated plastic wrapper. In addition, the UVC-LED treatment for 3 min reduced the L. monocytogenes concentration in F. velutipes by 0.47 log CFU/g. Moreover, the growth of L. monocytogenes in the treated mushrooms was slower than that of the untreated (control) ones. L. monocytogenes concentration in F. velutipes increased over 3 log CFU/g at 2℃ and 10℃ for 60 and 10 days, respectively. The growth of L. monocytogenes at the bottom of mushrooms was faster than that at the top at both the temperatures. These results indicate that the combined SAEW+UVC-W-LED treatment of plastic wrappers and the UVC-LED treatment of mushrooms can be used as potential hurdle technologies to control the risk of L. monocytogenes in mushrooms prior to packaging at farms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.269-276
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• 2016

This study was conducted to determine the inactivation effects of slightly acidic electrolyzed water (SAEW) on microorganisms attached to salted Chinese cabbage and food materials of kimchi, such as slice radish and green onion. In addition, changes in microbial and physicochemical quality of manufactured kimchi during storage at $4^{\circ}C$ for 4 weeks were investigated. Compared to the untreated control with tap water, total bacterial counts (TBC) of Chinese cabbage, slice radish, and green onion were reduced by 1.75, 1.68, and 1.03 log CFU/g at dipping times of 20 min, 5 min, and 10 min, respectively, upon treatment with 30 ppm SAEW at $40^{\circ}C$. Effect of microbial inhibition was higher in salted Chinese cabbage brined in 10% salt (w/v) of 30 pm SAEW at $40^{\circ}C$ than in untreated control with tap water, as indicated by 1.00 log CFU/g reduction. TBC of kimchi manufactured with materials treated with 30 ppm SAEW at $40^{\circ}C$ was not significantly affected compared to untreated control, although coliforms were remarkably reduced compared to the untreated control. At the beginning of storage (1 weeks), TBC and lactic acid bacteria (LAB) counts increased by approximately 9 and 7.66~8.18 log CFU/g, respectively, and coliforms were completely eliminated. The pH and acidity of kimchi at 2 weeks were 4.34~4.49 and 0.55~0.66%, respectively, and then slowly decreased. The texture (firmness) of kimchi decreased with storage time, but the difference was not significant. This combined treatment might be considered as a potentially beneficial sanitizing method for improving the quality and safety of kimchi.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.166-172
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• 2015

This study was performed to develop treatment method for reducing microbial contamination on Daruma (a semi-processed product of seasoned and dried squid) by combination of strong acidic hypochlorous water (SAHW) and ultrasonic waves (UW). The available chlorine concentration, oxidation reduction potential (ORP) and pH of SAHW were $69.67{\pm}0.58ppm$, $1071.33{\pm}4.16mV$ and 2.79, respectively. The 1.49 log CFU/g of viable cell count and 1.32 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of sodium hypochlorite solution (SHS) for 120 min. The 3.62 log CFU/g of viable cell count and 3.22 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 120 min. The antibacterial effects of SAHW were stronger than those of SHS at same available chroline concentration. SAHW treatment after washing strongly alkalic electrolyzed water (SAEW) showed better bactericidal effects than SAHW treatment only. The 4.0 log CFU/g of viable cell count was reduced, S. aureus was reduced below regulation limit (Log 2.0 CFU/g), and E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 90 min after washing with 20 times (w/v) of SAEW for 60 min. The viable cell number was reduced below detection limit and S. aureus was reduced below regulation limit when the Daruma was treated with 20 times (w/v) of SAHW for 60 min in ultrasonic washer. E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 10 min in ultrasonic washer. These results suggest that combination of SAHW and UW may be a good technique to reduce the microbial contamination in daruma.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1846-1853
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• 2010

The storage attributes of green juice prepared by washing Angelica keiskei with various washing solutions using air bubble method were investigated. The washing solutions were distilled water (DW), sodium hypochlorite electrolyzed water (SHEW), and slightly acidic electrolyzed water (SAEW). During storage at $4^{\circ}C$, the number of bacteria after 1 day was $>10^5$ CFU/mL when DW was used, whereas bacterial growth was $<10^5$ CFU/mL after 4 days when SHEW or SAEW was used. The pH and color were not changed, and the polyphenol content, electron donating ability and total antioxidant ability were decreased slowly with the increase of storage time. No significant difference in any of the measured properties was found among washing methods (p<0.05). Consequently, these results suggest the possible use of electrolyzed water for washing to enhance the shelf life of green juice with A. keiskei because SHEW and SAEW decreased bacterial growth without affecting other properties of the green juice.

• Food Science and Preservation
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• v.15 no.5
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• pp.622-629
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• 2008

This study investigated changes in quality characteristics of wrap- and vacuum-packaged peeled lotus roots treated with strong acidic electrolyzed acid water (SAEW pH 2.58, ORP 1,128 mV, HClO 105.0 ppm) or low alkaline electrolyzed water (LAEW pH 8.56, ORP 660 mV, HClO 73.8 ppm) as immersion liquids prior to packaging and storage at 5C. Immersion of peeled lotus roots in SAEW and LAEW reduced initial microbial load by about 1 log compared to treatment with tap water (TW). Hardness differences on storage were observed. However, reduction in PPO activity by electrolyzed water was not reproducible. Changes in Hunter's color value and the color difference value ($\Delta$) of peeled lotus roots immersed in 0.5% (w/v) sodium metabisulfite (SMS) and electrolyzed water were smaller than those of roots treated with TW prior to storage. Sensory characteristics measured during storage were best-preserved in lotus roots previously immersed in 0.5% (w/v) SMS or electrolyzed water, compared to TW. Immersionin electrolyzed water and vacuum packaging preserves the quality of peeled lotus roots in terms of microbial, visual, and sensory aspects, at levels comparable to those offered by storage after treatment with 0.5% (w/v) SMS.