• Journal of the East Asian Society of Dietary Life
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• v.27 no.1
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• pp.78-87
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• 2017

The objective of this study was to investigate the effects of various washing waters on the quality and safety characteristics of eggs during storage. Eggs were washed with tap water, 100 ppm of sodium hypochlorite, or 30 ppm of slightly acidic electrolyzed water and stored at $10^{\circ}C$ and $20^{\circ}C$. Effects of various washing waters on reduction of Salmonella Enteritidis and aerobic plate counts and survival of S. Enteritidis on egg shells were also analyzed at $10^{\circ}C$ and $20^{\circ}C$ for 25 days. As an index of quality, haugh unit, weight reduction, and pHs of egg white and egg yolk were measured. Reduction percentages of haugh unit and weight were higher at $20^{\circ}C$ than at $10^{\circ}C$. Egg qualities were less affected by tap water, slightly acidic electrolyzed water, and sodium hypochlorite, regardless of storage temperature. The greatest reductions in aerobic plate counts and S. Enteritidis were observed with slightly acidic electrolyzed water. The level of S. Enteritidis on egg shells gradually decreased during 20 days of storage at both $10^{\circ}C$ and $20^{\circ}C$, whereas S. Enteritidis survived longer at $20^{\circ}C$ than at $10^{\circ}C$. S. Enteritidis was not detected in eggs at $10^{\circ}C$, 2.13 log CFU/g of S. Enteritidis was detected in eggs washed with sodium hypochlorite after 20 days of storage at $20^{\circ}C$, indicating that S. Enteritidis penetrated into the egg shell during storage at $20^{\circ}C$. In conclusion, slightly acidic electrolyzed water increased microbial reduction and least affected quality of washed eggs. Thus, slightly acidic electrolyzed water can be recommended for washing of graded eggs, at retail markets.

• 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.

• Safe Food
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• v.7 no.2
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• pp.35-39
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• 2012

• 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.

• 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.24 no.2
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• pp.312-319
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• 2017

In the present study, disinfection efficacy of slightly acidic electrolyzed water [SlAEW, 30 ppm of effective chlorine at $20{\pm}1^{\circ}C$, oxidation-reduction potential (ORP) $562{\pm}23mV$, pH 6.4] on 4 kinds of vegetables (lettuce leaf, endive leaf, perilla leaf and kale leaf) was evaluated to obtain a microbial reduction characteristics which are necessary to design a process control for non-thermal sterilization of fresh vegetables. Active chlorine, residual chlorine, microbial counts and residual microbial counts, which are the key factors in the non-thermal sterilization process were measured by dipping them in SlAEW three times for 30 minutes in order to analyze the relationship between factors. Total microbial count was decreased mostly during the first 10 minutes of washing, and the limit value that can be reduced by immersion treatment was 3 log CFU/g for the total microbial count surviving in 4 kinds of vegetables. The total number of microorganism that can be reduced by washing in SIAEW for 10 min was found to be about 2 log CFU/g on average. In addition, the active chlorine decreased in the initial 10 minutes in 2.2 ppm, 2.0 ppm, 1.7 ppm and 2.5 ppm in lettuce, perilla leaf, endive leaf and kale leaf, respectively, and about 50-80% of the chlorine was reduced in the initial 10 min appear.

• 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 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 the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1296-1303
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• 2014

This study was conducted to develop predictive models for the growth of Bacillus cereus on carrot treated with slightly acidic electrolyzed water (SAcEW) and ultrasonication (US) at different storage temperatures. In addition, the inactivation of B. cereus by US with SAcEW was investigated. US treatment with a frequency of 40 kHz and an acoustic energy density of 400 W/L at $40^{\circ}C$ for 3 min showed the maximum reduction of 2.87 log CFU/g B. cereus on carrot, while combined treatment of US (400 W/L, $40^{\circ}C$, 3 min) with SAcEW reached to 3.1 log CFU/g reduction. Growth data of B. cereus on carrot treated with SAcEW and US at different temperatures (4, 10, 15, 20, 25, 30, and $35^{\circ}C$) were collected and used to develop predictive models. The modified Gompertz model was found to be more suitable to describe the growth data. The specific growth rate (SGR) and lag time (LT) obtained from the modified Gompertz model were employed to establish the secondary models. The newly developed secondary models were validated using the root mean square error, bias factor, and accuracy factor. All results of these factors were in the acceptable range of values. After compared SGR and LT of B. cereus on carrot, the results showed that the growth of B. cereus on carrot treated with SAcEW and US was slower than that of single treatment. This result indicates that shelf life of carrot treated with SAcEW and US could be extended. The developed predictive models might also be used to assess the microbiological risk of B. cereus infection in carrot treated with SAcEW and US.

• Korean Journal of Veterinary Research
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• v.60 no.3
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• pp.105-108
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• 2020

These days abattoirs' hygiene of Korea is regulated by Hazzard Analysis Critical Control Point (HACCP). Although 20 years have been left since first HACCP was adjusted in Korea, 12% of abattoirs got inconsistence on evaluations. Food poisoning caused by bacteria feces like pathogenic Escherichia coli and Salmonella has not decreased. These bacteria on meat cross-contaminate at the abattoir. Therefore, field verification of abattoir's critical control point (CCP) and experiments to find alternative ways of the CCP were conducted. The aerobic bacteria were measured before and after high-pressure water based washing process set as CCP in most abattoirs. Four parts of cattle carcasses were selected to apply sponge-swab method. The effects were < 1 log reduction which is not significant. Lactic acid (LC), chlorine dioxide (ClO₂) and slightly acidic electrolyzed water (SAEW) were used to measure the effect of reducing bacteria on beef by the different time. LC has 1.24-2.02 log reduction for aerobic bacteria. ClO₂ has 1.44-1.96 log reduction for aerobic bacteria. SAEW has 1.1-1.91 log reduction for aerobic bacteria. There was significant difference according to concentrations (p < 0.05). This study presents legitimacy for hygiene improvement of CCP by field verification. In addition, chemical disinfectants that can be mechanically applied have better reduction effects of high-pressure washing.