• 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.7 no.4
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• pp.395-402
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• 2000

To enlarge application field of electrolyzed acid-water(EAW) on food industry, the changes of EAW properties by storage conditions and heating were investigatet. It was showed that storing EAW in closed container is mon effective to keep up the oxidation-reduction potentials(ORP), hyperchloride content and pH than stored in opened ones. ORP of EAW stored in closed container could be kept mon than 1 month as 1,150 mV levels. Ruing heating from 2$0^{\circ}C$ to 95$^{\circ}C$, ORP was increased to 1,150 mV levels at 95$^{\circ}C$ after gradual decrease to 5$0^{\circ}C$. Tyrosinase activity was decreased approximately to 26%~35% in EAW having a 950 mV~1,140 mV ORP. Also it was confirmed that EAW has anti-browning effect as sliced apple and potato, and their juices treated with EAW had conspicous difference in their $\Delta$E value. 12 kinds of pesticides such as aldrine, capful diazinon, diedrin, $\alpha$-endosulfan $\beta$-endosulfan, endosulfan sulfate, endrin, $\alpha$-BHC, o,p'-DDT, procymidone, PCNB added in EAW were recovered from ND~73.6% comparing to ones added in distilled water. The recovered amounts of pesticides, procymidone and diazinon in lettuce after soaking in EAW were 1.12 ppm and ND, compared with those of amounts soaked in distilled water were 3.67 ppm and 3.05 ppm respectively. So, it seems that EAW has potentials to promote the degradation of pesticides.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.106-114
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• 2019

The effect of physical and chemical treatments to reduce staphylococcal phages was investigated. To determine impact of physical treatment on viability of phages, two staphylococcal phages (SAP84 and SAP89) were treated with multiple heat ($55^{\circ}C$ and $60^{\circ}C$) and pH (pH4, 7, 10) conditions. Viability of SAP 84 was dramatically reduced at 60C and SAP 89 was completely inactivated at 60C within 25 min. Overall, the two phages were stable under all the pH conditions tested except for the SAP 89 at pH 10. Treatments, a 10% FAS (Ferrous Ammonium Sulfate) solution and various density of ethanol and sodium hypochlorite were used to reduce the two phages. SAP 84 was unstable in 50% and 70% ethanol. However, SAP 84 and SAP 89 showed high tolerance after exposure to 100 ppm of sodium hypochlorite which is known as an effective sterilizer. As soon as the two phages were treated with 10% FAS, which is used as a virucidal agent, they were inactivated and did not form any plaque. The result of this study provides additional evidence that staphylococcal phages can be controlled by various physicochemical treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1743-1749
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• 2011

The microbial reduction and quality characteristics of salted Chinese cabbage using electrolyzed water were investigated. The electrolyzed water was used to control the microbes in the processes of primary washing, salting, and secondary washing. The total bacteria, lactic acid bacteria, coliform, pH, salinity, vitamin C, and total sugar were analyzed. After primary washing by electrolyzed water, the total bacteria populations were reduced to 2.78 log cfu/g, and the coliform populations were similarly reduced. After secondary washing by electrolyzed water, the total bacteria population of Chinese cabbage was reduced to a maximum of 1.5 log cfu/g. The salinity of Chinese cabbage and salting solutions increased rapidly over three hours, and then increased slowly. The sterilization effect of electrolyzed salting water could not last beyond 3 hours, because the OHCl concentration of electrolyzed water was reduced by over 90% at the third hours of the salting process. Vitamin C was reduced and total sugar did not change regardless of treatments during the salting process. Consequently, electrolyzed water was effective to remove microbes from salted Chinese cabbages.

• Journal of Ocean Engineering and Technology
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• v.31 no.3
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• pp.248-255
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• 2017

Many rivers and seas have been affected by environmental contamination. Therefore, city water supplies often require a high-degree purification treatment to provide safe drinking water. However, in order to achieve a high-degree purification treatment, a large amount of chlorine has to be added to sterilize city drinking water. The added chlorine reacts chemically with water and forms hypochlorous and chlorine ions. The hypochlorous ionizes with hypochlorous ions and hydrogen ions. As a result, the city water contains a large amount of chlorine ion. As such, when city water is used with domestic boilers, many kinds of heat exchangers, and the engines of vehicle and ships, there are often corrosion problems. In this study, alkali water was electrochemically made by electrolysis of city water, and corrosion properties between alkali and city water were investigated with an electrochemical method. Most of the chlorine ions are thought to not be contained in the alkali water because the alkali water is created in the cathodic chamber with an electrolysis process. In other words, the chlorine ion can be mostly removed by its migration from a cathodic chamber to an anodic chamber. Moreover, the alkali water also contains a large amount of hydroxide ion. The alkali water indicated relatively good corrosion resistance compared to the city water and the city water exhibited a local corrosion pattern due to the chlorine ion created by a high-degree purification treatment. In contrast, the alkali water showed a general corrosion pattern. Consequently, alkali water can be used with cooling water to inhibit local corrosion by chlorine ions in domestic boilers, various heat exchangers and the engine of ships and for structural steel in a marine structure.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.729-734
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• 2008

The higher valence state of iron i.e., Fe(VI) was employed for the treatment of Cu(II)-EDTA in the aqueous/waste waters. The ferrate(VI) was prepared through wet oxidation of Fe(III) by sodium hypochlorite. The purity of prepared Fe(VI) was above 93%. The stability of Fe(VI) solution decreased as solution pH decreased through self decomposition. The reduction of Fe(VI) was obtained by using the UV-Visible measurements. The dissociation of Cu(II)-EDTA complex through oxidation of EDTA using Fe(VI) and subsequent treatment of organic matter and metal ions by Fe(III) reduced from Fe(VI) in bench-scale of continuous flow reactor were studied. The removal efficiencies of copper were 69% and 79% in pH control basin and reactor, respectively, at 120 minutes as retention time. In addition, Cu(II)-EDTA in the reactor was decomplexated more than 80% after 120 minutes as retention time. From this work, a continuous treatment process for the wastewater containing metal and EDTA by employing Fe(VI) as muluti-functional agent was developed.

• Food Science and Preservation
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• v.10 no.1
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• pp.99-105
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• 2003

This study was carried out to investigate the efficacy of surface sterilization and the physicochemical properties of electrolyzed water manufactured from various electrolytic diaphragm and electrolyte. Physical properties of electrolyzed water manufactured from the diaphragm system were the most effective at the following conditions; the distance between diaphragms was 1.0 mm and the supplying rate of 20% NaCl was 6 mL/min. The ORP, HClO content and pH at above conditions were 1,170 mV, 100 ppm and 2.5, respectively. And two stage electrolyzed system was more effective than one stage electrolyzed water manufactured from non-diaphragm system, with 4 mL/min supplying rate of 20% NaCl, was similar to the most effective diaphragm system. But ORP, HClO content and pH were abut 800 mV, 200 ppm and 9 level, respectively. Sealed electrolyzed water could be preserved more than one month at room temperature with ORP of 750 mV in non-diaphragm system and 1,150 mV in diaphragm system, and HClO content of 100 ppm. Twelve kinds of microorganism tested were sterilized within 30 seconds from initial total counts of 10$\^$5/∼10$\^$6/cfu/ml by electrolyzed water. Though the ORP and HCIO contents of electrolyzed water manufactured from various electrolyte were higher in order of NaCl>KCl>CaCl$_2$, there were no difference between the electyolytes in the efficacy of sterilization. Salmonella typhi and Vibrio Proteolyticus were also sterilized by electrolyzed water manufactured from elctrolytes of NaCl CaC1$_2$and KCl

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.80-86
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• 1978

This study was carried out in order to know the effect of T. T. C. reaction on antibiotics, cleanser, disinfectants, pH, acidity and station of culture a bacterial Streptococcus thermophilus was used to 2.3.5-triphenyl tetrazolium chloride reduction test for the detection of residual antibiotics in milk were tested. The results obtained were summarized as follows. 1. The T. T. C. reaction was most sensitive in the group of penicillin as 0.02~0.05 IU and also it was less sensitive in Streptomycin and various broad antibiotics except Vibramycin, Synthomycin and Teramycin but it was least sensitive in Streptomycin group. 2. For ther T. T. C. reaction test on cleanser, the positive reaction was appeared above 0.7% of Hi-Ti and 0.1% of NaOH solution respectively. 3. For the T. T. C. test reaction on disinfectants, the positive reaction was occured on 200~500 ppm solution of sodium-hypochlorite and chloride-lime, 0.15~0.35% solution of phenol, cresol and Iode-K. 4. The optimum temperature was $35{\sim}37^{\circ}C$ and proper culturing time was 12 to 18 hours for propagation culturing. 5. The suspect positive reaction was tested above pH 5.0 and the positive reaction was appeared above 0.21% of acidity.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.149-155
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• 2012

Although bacterial outbreaks from ready-to-eat foods such as sprouts have increased, the information on microbial biocontrol by means of sanitizers is limited. Twenty sprouts of red cabbage, baby radish, alfalfa, and broccoli each were collected from the wholesale markets in Seoul. Ethanol and organic acids including acetic acid, citric acid, and lactic acid were used to control the amount of mesophilic bacteria and Bacillus cereus. Sanitizer mixtures of ethanol and organic acids showed a remarkable reduction of viable counts and, in particular, the sanitizer mixture comprised of 20% ethanol and 1% lactic acid seemed to be best by a reduction of 7~8 log CFU/g on the sprouts after a 10 minute exposure. At the same time, the sanitizer comprised of 20% ethanol and 1% lactic acid showed the same reduction for Escherichia coli, Salmonella typhimurium, B. cereus, Staphylococcus aureus, and Enterococcus faecalis, with more effect toward the Gram-negative bacteria. Sensory evaluation by texture, browning, off-flavour, and overall acceptability seemed better just after treatment when compared to one day after treatment with the sanitizer. Therefore, the sanitizers of ethanol-organic acid might be an effective means to control the bacterial contamination of sprouts in palce of sodium hypochloric acid.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.877-882
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• 2013

The application of ultrafiltration (UF) and microfiltration (MF) membranes has been increased for drinking water purification. The advantages of UF/MF membrane process compared to conventional treatment processes are stable operation under varying feed water quality, smaller construction area, and automatic operation. Most membrane treatment plants are designed with polymeric membranes. Recently, some studies suggested that the process of treating surface water with ceramic membranes is competitive to the application of polymeric membranes. Higher water flux, less frequent cleaning, and much longer lifetime are the advantages of ceramic membrane comparing to polymeric membrane. Therefore, this research focused on the application of ceramic MF membrane pilot plant at the slow sand filtration plant. The ceramic membrane pilot plant has three trains that used raw water and sand filtered water as a feed water, respectively. For optimizing the pilot plant process, the coagulation with PACl coagulant was used as a pretreatment of ceramic membrane process. In addition, CEB (Chemical Enhanced Backwash) process using $H_2SO_4$ and NaOCl was used for 1.5 days, respectively. The experimental results showed that applying the optimum coagulant dose before membrane filtration showed enhancing membrane fluxes for both raw water and sand filtered water. Also, when using raw water as a feed of membrane, minimum fouling rate was 2.173 kPa/cycle with 25 mg/L of PACl and when using sand filtered water, the minimum fouling rate was 0.301 kPa/cycle with 5 mg/L of PACl.