• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1430-1437
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• 2009

Functional bread was manufactured with single cell detritus (SCD) of sea tangle. The optimum ingredient formula for SCD bread was determined based on mixture model. Flour and water reduced max weight, strength, hardness and specific loaf volume, whereas the increased SCD reversed the volume change of dough. Flour increased $L^*$ and $b^*$ values of SCD bread, while SCD decreased. Flour and water decreased $a^*$ value, while SCD increased. Max weight, strength, hardness, specific loaf volume, $b^*$ value and water holding capacity (WHC) were linear model on ANOVA table, whereas distance, volume change of dough, $L^*$ and $a^*$ values were nonlinear model. The response constraint coefficient showed that SCD influenced texture of SCD bread more than flour and water did, whereas water influenced the volume change of dough, specific loaf volume and WHC more than flour and SCD did. Moreover, flour influenced color value more than did water and SCD. Distance and $a^*$ value fitted nonlinear model with interaction terms for flour-SCD and water-SCD. Optimum ingredient formula for SCD bread was: flour, 48.25%; water, 30.89%; SCD, 3.86%. Sensory evaluation of SCD bread was a little lower than industrial bread and electrolyzed SCD bread.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.79-86
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• 2017

Ballast water filled into and discharged from the ballast tank of a ship has a negative impact on local marine environment due to various aquatic organisms contained therein. The IMO developed and adopted "The International Convention for the Control and Management of Ships Ballast Water and Sediments, 2004" with the purpose of protecting the marine environment from transfer of harmful aquatic organisms in ballast water carried by ships. The IMO BWM Convention was approved in September 2016 and ships must be equipped with ballast water management system after September 2017. Ships' ballast water treatment methods are divided into using active substances as electrolytic type, ozone type, chemical dosing type and using physical treatment type as filter type, ultraviolet type. It is also used with a combination of two methods. Electrolysis is superior in terms of cost and efficiency. In this study, basic principles, components, and land base test contents of electrolysis ballast water treatment system, a direct electrolyzed ballast water treatment system, were examined. Land base test was conducted with 300m3/h capacity device at the KIOST Geoje plant where the government test facility was installed. This test validated that the system meets IMO standards.

• 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.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.446-453
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• 2009

This study was conducted to find condition of improving the quality of peach by using surfacing washing system. The rate of weight loss of A,B groups were showed slower decreasing trend than CT group and the value of soluble solid degree was not different significantly among all groups from the results of stored peach treat with surface washing system of peach in the first experiment. The colory value of surface were increased with increasing storage period in all treatments. Browning pace of A,B groups were slower than control. Emission of carbon dioxide was increased from the results of respiration rate, 6-10 mL/kg/hr $(10^{\circ}C)$ and 32-41 mL/kg/hr $(25^{\circ}C)$. In second experiment with surface washing system of peach, the value of soluble solid was showed with similar value from 10 $Brix^{\circ}$ to 13 $Brix^{\circ}$. The pace of soft rot of EW groups were lower than CT groups from the results of hardness during storage period. The results of colory value was not showed with significant difference in $15^{\circ}C$ and $20^{\circ}C$ storage temperature but changed to browning in EW groups. The moisture contents was from 85% to 90% in all groups. And the count of total microorganism of EW groups were lower than control. Also total coliform of EW groups were negative. In sensory evaluation, washing peach was showed higher value with significant difference in all acceptability.

• Journal of Microbiology and Biotechnology
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• v.23 no.12
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• pp.1708-1716
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• 2013

Conventional molecular detection methods cannot distinguish between viable and dead Escherichia coli O157 cells. In this study, the loop-mediated isothermal amplification (LAMP) method combined with propidium monoazide (PMA) treatment was developed to selectively detect viable E. coli O157 cells. Four primers, including outer primers and inner primers, were specially designed for the recognition of six distinct sequences on the serogroups (O157) of the specific rfbE gene of the E. coli O157 genome. PMA selectively penetrated through the compromised cell membranes and intercalated into DNA. Amplification of DNA from dead cells was completely inhibited by $3.0{\mu}g/ml$ PMA, whereas the DNA derived from viable cells was amplified remarkably within 1 h by PMA-LAMP. Exhibiting high sensitivity and specificity, PMA-LAMP is a suitable method for evaluating the inactivation efficacy of slightly acidic electrolyzed water in broth. PMA-LAMP can selectively detect viable E. coli O157 cells. This study offers a novel molecular detection method to distinguish between viable and dead E. coli O157 cells.

• Journal of Hydrogen and New Energy
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• v.34 no.2
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• pp.155-161
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• 2023

Recently, a study on alternative and renewable energy is being conducted due to energy depletion and environmental problems. In particular, a hydrogen has the advantage of converting and storing the remaining energy into water-electrolyzed hydrogen through renewable energy generation. In general, due to reasons such as insulation problems, a study on high-pressure hydrogen storage tanks and related parts has recently been conducted. However, in the case of liquid hydrogen, the volume can be reduced by about 800 times or more compared to high-pressure hydrogen gas, so the study on this is needed as a technology that can increase energy density. In this study, the evaporation characteristics were analyzed under fixed heat flux conditions for liquid hydrogen storage tanks and the change in thermal stratification according to sloshing was analyzed. The heat flux condition was fixed at 250 W/m² and the horizontal resonance frequency of the primary mode was applied to the storage tank. As a result, it was confirmed that the thermal stratification phenomenon decreased compared to the case where the slashing was not present due to forced convection when the slashing was present.

• Food Science and Preservation
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• v.17 no.3
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• pp.405-409
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• 2010

Surface cleaning is both essential and troublesome when a consumer seeks to eliminate soil attached to the surface of fresh ginseng because all ginseng purchased in the market is covered with soil, reflecting the post-harvest situation. To facilitate ginseng use at home, a fresh-cut type of ginseng is required. As a first step toward production of such ginseng, several washing and dipping treatments were investigated with respect to surface cleaning and reduction of microbial populations on fresh ginseng. In terms of microbial distribution on the surface of fresh ginseng, higher levels of viable bacteria (6.63 log CFU/each) and fungi (5.12 log CFU/each) were present on the rhizome head than on other regions of the root. Of the washing treatments tested, hand-brushing was effective for surface cleaning and to reduce microorganism levels on fresh ginseng, but use of a high-pressure water spray followed by hand-brushing was optimally effective. To further reduce the levelsof microorganisms on the surface of fresh ginseng after washing, additional dipping treatments in 70% (v/v) ethanol and electrolyzed acidic water (at pH 2.3) were somewhat effective but showed no significant differences compared with other dipping treatments tested, including a 3 ppm ozone solution, a 200 ppm sodium hypochlorite solution, or hot water at $50^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.74-80
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• 2015

In this study, the microbial control effect after treatment of washing solutions (tap water, electrolyzed water, chlorine dioxide solution) and quality changes were investigated when Kwamegi is produced by means of the cold air drying. The initial moisture rate of the sample was 56.62% before drying. At the beginning of drying period, moisture rate sharply fell down but as the experiment progressed, moisture reducing rate was smoothly decreased. The color difference of Kwamegi before drying was 42.40, but it was reduced depending on the increment of drying temperature and time. TBA value of the initial sample was 0.219, rancidity were increased continuously when drying progressed. Total amino acid content was showed the highest value at $25^{\circ}C$ for 36h and the lowest at $40^{\circ}C$ for 12h. From the fatty acids analysis, major fatty acids were consisted of the 14:0, 16:0 and 18:1 (18.1520.96%, 28.0632.51% and 17.0619.81%, respectively). The microbial control effect was biggest when Kwamegi was washed with chlorine dioxide 100ppm for 60s. The microbe of the Kwamegi, Pseudomonas sp. and Pseudomonas putida were identified.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.6
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• pp.329-333
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• 2016

Disinfection by electrolysis would be useful for small wastewater treatment plant, combined sewer overflow, ballast water, swimming pool, and fish farming, where the transport, storage, and the use of chlorine gas is limited. This study investigated the feasibility of the electrolysis of dilute hydrochloric acid (HCl) for disinfection. The effects of HCl concentration, voltage and reaction time on the generation of oxidizing agents, HOCl, $O_3$, and $H_2O_2$, were examined in a series of batch test. The highest current efficiency was 99.3% which was found at 2.2%, 3 V, and 5 min of HCl concentration, voltage, and reaction time, respectively. Continuous electrolysis at 2.2% HCl, 3 V, and 5 min of the hydraulic retention time showed 97.4% of the current efficiency. Addition of sodium chloride up to 20 g/L linearly increased the oxidizing agents production. 92.2% of total coliforms were removed by the contact with the electrolyzed water.

• Food Science and Preservation
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• v.15 no.2
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• pp.169-173
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• 2008

Bacillus subtilis subsp. subtilis constitutes 90% of the total viable bacteria present on Capsosiphon fulvescens. We found that hydrogen peroxide (50 ppm) and NaOCl (50 ppm) were more effective than electrolyzed water (EW, 50ppm) against B. subtilis subsp. subtilis that was isolated from this seaweed. Relative to a control, 50 ppm hydrogen peroxide reduced the total viable population by $1.8{\pm}0.4$ log CFU/g, whereas 50 ppm EW increased the total viable population by $1.7{\pm}0.5$ log CFU/g. CFUs were evaluated following 30 days of storage at $4^{\circ}C$ using air- and vacuum-packaging. Samples treated with 50 ppm hydrogen peroxide and NaOCl showed a $1.6{\pm}0.1$-fold decrease in initial hardness ($7.9{\times}10^6dyne/cm^2$), while the samples treated with 50 ppm EW had a $2.1{\pm}0.1$-fold decrease in initial hardness ($7.9{\times}10^6dyne/cm^2$). Again, measurements were performed after storage at $4^{\circ}C$ for 20 days. This study indicates that B. subtilis subsp. subtilis is the most common contaminant in aerobically or anaerobically packaged seaweed and should therefore be the main target for quality control during long-term storage. Hydrogen peroxide and NaOCl are more effective than EW in inhibiting B. subtilis subsp. subtilis and in reducing total bacterial loads in air- and vacuum-packaged seaweed.