• Food Science and Preservation
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• v.18 no.6
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• pp.875-883
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• 2011

Brown rice vinegar was made from brown rice mash with different brewing starter addition rates in static culture, and its quality characteristics were investigated. As a result, the amounts of alcohol produced in the fermentation process were shown to be 9.1, 8.8, 8.6 and 8.5% in the Nuruk 75 : crude enzyme 25 (B), Nuruk 50 : crude enzyme 50 (C), Nuruk 25 : crude enzyme 75 (D) and Nuruk 0 : crude enzyme 100 (E), respectively. The higher the percentage of crude enzyme added was, the lower the alcohol content that was produced. Nuruk 100 : crude enzyme 0 (A) was appeared to contain the lowest alcohol content (7.7%). In addition, the titratable acidity in all the groups was about 0.7%. The final titratable acidity (BV) of brown rice vinegar made with static culture was the highest (approximately 5.2%). The initial pH appeared to be between 3.6~4.0 and steadily decreased as the fermentation progressed, and the pH was almost unchanged after 15 day fermentation. The examination of the changes in the organic acids showed that the acetic acid content was similar in all the groups, and that the single starter added (AV, EV) group had much more other organic acids than the mixed starters added (BV, CV, DV) group. From these results, the mixed starters (Nuruk and crude enzyme) added group appeared to be superior to the single starter added in terms of alcohol production ability and vinegar quality. As the future aging process, however, is expected to change the flavor components and sensory characteristics, studies on various quality factors of vinegar are needed.

• Korean Journal of Remote Sensing
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• v.34 no.6_1
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• pp.1041-1053
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• 2018

In this study, a real-time storage level and capacity monitoring and forecasting system for Yongdam Dam watershed was developed using high resolution satellite image. The drought indices such as Standardized Precipitation Index (SPI) from satellite data were used for storage level monitoring in case of drought. Moreover, to predict storage volume we used a statistical method based on Principle Component Analysis (PCA) of Singular Spectrum Analysis (SSA). According to this study, correlation coefficient between storage level and SPI (3) was highly calculated with CC=0.78, and the monitoring and predictability of storage level was diagnosed using the drought index calculated from satellite data. As a result of analysis of principal component analysis by SSA, correlation between SPI (3) and each Reconstructed Components (RCs) data were highly correlated with CC=0.87 to 0.99. And also, the correlations of RC data with Normalized Water Surface Level (N-W.S.L.) were confirmed that has highly correlated with CC=0.83 to 0.97. In terms of high resolution satellite image we developed a water detection algorithm by applying an exponential method to monitor the change of storage level by using Multi-Spectral Instrument (MSI) sensor of Sentinel-2 satellite. The materials of satellite image for water surface area detection in Yongdam dam watershed was considered from 2016 to 2018, respectively. Based on this, we proposed the possibility of real-time drought monitoring system using high resolution water surface area detection by Sentinel-2 satellite image. The results of this study can be applied to estimate of the reservoir volume calculated from various satellite observations, which can be used for monitoring and estimating hydrological droughts in an unmeasured area.

• Korean journal of food and cookery science
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• v.1 no.1
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• pp.74-81
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• 1985

For this research, the Atka-fisher which are used commonly in many homes for baking and broilling were broiled by an iron baking method, a pan baking method, a grill baking method and a microwave baking method respectively after 20 hours salting with 3% salt concentration of fish muscle weight. This thesis has an intention of appreciating the tastes according to each baking method through a sensory test, of examining the corelation between the change of texture measured by Rheometer and a sensory test and of comparing the changes of chemical component of the fish. The results were as follow: 1. The appearance of the broiled Atka-fish maintained a good appearance by the iron baking method and the grill baking method. In the color, the iron baking method and the grill baking method by direct :fire resulted a good score too. In the flavor, there was a significant difference between the grill baking method and the microwave baking method while there was no difference between the iron baking method and the pan baking method. The result of tenderness showed that the pan baking method has the highest score. Difference between the iron baking method and the pan baking was not significant. There was no difference in tenderness between the grill baking method and the microwave baking method. The iron baking method showed-the highest score in juciness and the microwave baking method stowed the highest score in acceptability however the differences were not significant. 2. As a result of the measurement of the texture by Rheometer, the iron baking method and the grill baking method showed higher score than other methods in hardness and chewiness. In springiness and cohesiveness, there was no significant difference among methods. As a result of the measurement of the texture by Rheometer, the corelation with a sensory test was considered to be low. 3. After broil, the cooking retention was the highest in the pan baking method and the moisture content was the highest in microwave baking method. Nitrogen content was the highest in the iron baking method. Fat content was the highest in the iron baking method, followed by the grill baking method, the pan baking method, and the microwave baking method. Free amino acid content was the highest in the iron baking method, followed by the grill baking method, the pan baking method and the micro-wave baking method.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.249-254
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• 1997

The constructed wetland system which is applicable to rural wastewater treatment was examined by pilot plant experiment. Removal rates of nutrients including nitrogen and phosphorus and total coliform were evaluated. The $NH_4\;^+$ concentration of the influent was in the range of 91.57 to 275.88mg/l and the effluent concentration was about 40% lower than the influent. The decreasing of the $NH_4\;^+$ concentration might be due to volatilization, plant uptake, adsorption onto soil particles, and mainly nitrification. However, generally concentrations of $NO_2\;^-$ and $NO_3\;^-$ were increased in the effluents compared to the influent concentrations, which implies that nitrogen components in the system were nitrified. Overall, the average removal rate of the nitrogen was about 5% which seems inadequate as a wastewater treatment system, and this system needs improvement on nitrogen removal mechamism. The removal rate of the phosphorus was quite high and effluent concentration was very low. Reason for high removal rate of the phosphorus might be mainly strong adsorption characteristic onto soil particles. The average removal rate of the total coliforms was about 83%, and main removal mechanisms are thought to be adsorption onto soil and inability to compete against the established soil microflora. From the results of the study, the constructed wetland system needs to be improved in nitrogen removal mechanism for field application.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.521-527
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• 2008

Acanthopanacis cortex extracts added Yakju was manufactured and then fermentation and quality characteristics of Yakju were examined. Acanthopanacis cortex extracts added Yakju showed totally similar characteristics with the non-extract added Yakju of control groups. The pH showed almost no change to pH 4.0 after 6 days of fermentation and it was decreased only once in only fermentation time of 3 days. The acidity of Acanthopanacis cortex extracts added group showed no difference to the control group. The sugar obrix and reducing sugar content showed decrease in all two groups in the initial fermentation stage; however, it showed slow decrease as the late fermentation stage. The Acanthopanacis cortex extracts added Yakju showed less alcohol content than the control group in the initial fermentation stage. However, after 6 days of fermentation, the Acanthopanacis cortex extracts added Yakju showed more alcohol contents and constant increase till the final fermentation day. The pH, acidity, reducing sugar and alcohol content showed rapid changes between fermentation days 0 through 3. Therefore, it means that the Acanthopanacis cortex extracts added Yakju fermentation actively takes place between the days 0 through 3. Organic acids detected in Yakju were acetic, lactic, oxalic, malic and succinic acids. The acetic acid was the highest among the total acid contents. Eleutheroside E and chlorogenic acid, known as the effective components of Acanthopanacis cortex, showed stable status without changes in component content till stage two fermentation. The contents of eleutheroside E and chlorogenic acid were $7.61\pm0.39{\mu}g/mL$ and $3.63\pm0.18{\mu}g/mL$ on the final fermentation day, respectively. The fusel oil was slightly detected in both groups with values of $0.08\pm0.001{\sim}0.86\pm0.03mg%$ in n-propyl alcohol, isobutyl alcohol and isoamyl alcohol content. The Acanthopanacis cortex extracts added group was similar to the control group in the overall sensory test.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.627-635
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• 2019

Cement-asbestos slate is the main asbestos containing material. It is a product made by combining 10~20% of asbestos and cement components. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. When the asbestos enters the human body, it causes cellular damage or deformation, and is not discharged well in vitro, and has been proven to cause diseases such as lung cancer, asbestos, malignant mesothelioma and pleural thickening. The International Agency for Research on Cancer (IARC) has designated asbestos as a group 1 carcinogen. Currently, most of these slats are disposed in a designated landfill, but the landfill capacity is approaching its limit, and there is a potential risk of exposure to the external environment even if it is land-filled. Therefore, this study aimed to exam the possibility of detoxification of asbestos-containing slate by using exothermic reaction and heat treatment. Cement-asbestos slate from the asbestos removal site was used for this experiment. Exothermic catalysts such as calcium chloride(CaCl₂), magnesium chloride(MgCl₂), sodium hydroxide(NaOH), sodium silicate(Na₂SiO₃), kaolin[Al₂Si₂O₅(OH)₄)], and talc[Mg₃Si₄O₁₀(OH)₂] were used. Six catalysts were applied to the cement-asbestos slate, respectively and then analyzed using TG-DTA. Based on the TG-DTA results, the heat treatment temperature for cement-asbestos slate transformation was determined at 750℃. XRD, SEM-EDS and TEM-EDS analyses were performed on the samples after the six catalysts applied to the slate and heat-treated at 750℃ for 2 hours. It was confirmed that chrysotile[Mg₃Si₂O₅(OH₅)] in the cement-asbestos slate was transformed into forsterite (Mg₂SiO₄) by catalysts and heat treatment. In addition, the change in the shape of minerals was observed by applying a physical force to the slate and the heat treated slate after coating catalysts. As a result, the chrysotile in the cement-asbestos slate maintained fibrous form, but the cement-asbestos slate after heat treatment of applying catalyst was broken into non-fibrous form. Therefore, this study shows the possibility to safely verify the complete transformation of asbestos minerals in this catalyst- and temperature-induced process.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.163-170
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• 2007

The effects of olive oil on the quality characteristics of pressed ham were investigated. Five different treatments were carried out varying the amount of olive oil added to pressed ham. for the control, 10% back fat among the total ham components was added without any olive oil. For the first treatment, 5% olive oil within the lard component was added into the pressed ham. The 2nd, 3rd and 4th treatments included 10%, 15% and 20% olive oil, respectively. Manufactured pressed hams containing olive oil were vacuum packaged and then stored for 28 days at $4^{\circ}C$. The crude protein and crude fat were not significantly different between the control and olive oil treated hams. The moisture and crude ash contents of olive oil treated hams was significantly lower than that of the control(p<0.05). There was no significant difference in pH between the control and olive oil treated hams. The pH increased during the first 7 days of storage and then decreased somewhat for the remainder of the 28 day storage period for all treatments. The meat color $b^*$ value of olive oil treated hams was higher than that of the control, whereas the meat color $a^*$ value decreased with the inclusion of olive oil. Neither value changed during the period of storage. There was no significant difference in texture between the control and olive oil treated hams throughout the storage period. In summary, pressed ham manufactured with added olive oil showed no change in physico-chemical properties and texture characteristics. Thus, it may be assumed that high quality pressed ham can be manufactured with increased monounsaturated fatty acid content.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.245-250
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• 2010

The post-harvest concentration change of four kind of pesticides, captan, chlorpyrifos, methidathion and kresoxim-methyl was investigated with the storage period for the import fruit. Then the post-harvest concentration was set to 1000, 250, 400 and 157 $mgkg^{-1}$ for captan, chlorpyrifos, methidathion and kresoxim-methyl respectively. In case of captan, 0.9-12.5 $mgkg^{-1}$ in total fruit base and ND-0.23 $mgkg^{-1}$ in the sarcocarp were measured after atomization and 0.7-3.2 $mgkg^{-1}$ in total fruit base and ND-0.67 $mgkg^{-1}$ in the sarcocarp were measured after four week. For chlopyrifos, menthidathion, and kresoxim-methyl 0.4-2.2, 0.7-3.1 and 1.3-2.1 $mgkg^{-1}$ in total fruit base and ND-0.32, ND-0.05 and ND-0.16 $mgkg^{-1}$ in the sarcocarp were measured after atomization respectively. After four week 0.3-0.9, 0.4-2.0 and 1.3-1.8 $mgkg^{-1}$ in total fruit base and ND-0.02, ND-0.05 and ND-0.15 $mgkg^{-1}$ in the sarcocarp were investigated for other three pesticides. The concentration decreasing ratio of pesticides was largest for captan, 52% and other components were in order of chlopyrifos, menthidathion, and kresoxim-methy, 47, 41, 11% each other.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.121-129
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• 2020

This study investigated the change of benthic macroinvertebrates community due to erosion control dams installed in Wonju, Gangwon by comparing the data before and after a rainy season. It selected a closed-type erosion control dam (boulder stone), an open-type erosion control dam (buttress), and a control area and surveyed two upstream points and two downstream points four times between March and September 2019. The flow velocity mostly increased in the closed-type, open-type, and control areas but decreased in St. 3 after the rainy season. The number of benthic macroinvertebrates species and their populations mostly decreased after the rainy season, and the rate of decrease in the populations in the open-type and control areas were more similar than the closed-type area. Species and populations of the EPT groups mostly decreased after the rainy season. A result of the similarity analysis showed that the closed-type and open-type areas were separated by 38.4% with the control area before the rainy season, but the open-type and control areas were separated by 51.3% with the closed-type area after the rainy season. A result of the principal components analysis (PCA) based on axis 1 showed that the closed-type area had a positive value before and after the rainy season, and the open-type and control areas had a negative value before and after the rainy season. The open-type area was more correlated with the control area than the close type. The analysis of the EPT groups showed the distribution of Ephemeroptera in the closed-type area and Trichoptera in the open-type and control areas. The result of this study shows that the installation of erosion control dam can cause changes in benthic macroinvertebrates community and that the open-type area had a smaller difference community difference from the control area after the rainy season than the closed-type area.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.166-172
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• 2001

In order to increase ginsenoside content, to reduce chemical change, to shorten extracting procedure, new methods of extraction and fractionation of crude ginseng saponin were established and compared for their chemical composition. Those are hot MeOH extraction/n-BuOH fractionation (BuOH method) and hot MeOH extraction/Diaion HP-20 adsorption/MeOH elution (HP-20 method), which are already known methods, and additional three new methods: hot MeOH extraction/cation AG 50W $adsorption/H_2O$ elution/n-BuOH extraction (AG 50W method), cool MeOH extraction/Diaion HP-20 adsorption/MeOH elution (cool extraction method) and direct extraction with EtOAc/n-BuOH (direct extraction method). AG 50W method provided a crude saponin showing the highest content of ginsenosides of 61.5% and the lowest contents of protein and free amino acids of 0.93% and 0.19%, respectively. The protein content was the highest as 14.18% in the crude saponin by HP-20 method, while free sugar content was the highest as 13.5% by BuOH method, indicating that these are factors that lower the rate of ginsenoside in crude saponins by those methods. On the other hand, it was revealed that AG 50W method produced large amount of prosapogenins during the pass through the cation exchange resin (AG 50W) column being strongly acidic. Crude saponin from direct extraction method showed relatively higher composition of ginsenoside $Rg_1$ and Re. The results suggest that contents and composition of ginsenosides and other chemical components in crude ginseng saponin greatly depend on the condition of the extraction and fractionation.