• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.541-546
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• 2009

The objectives of this study were to evaluate the physico-chemical and sensory characteristics of a Korean traditional alcoholic beverage (yakju) prepared using different nuruk (Korean-style koji) concentrations and yeasts such as the fusant FA776 and Saccharomyces cerevisiae KOY-1, respectively. The fusant FA776, which has alcohol-fermenting and starch-utilizing properties, was formed by Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC1804. The fermentation trial was conducted in a 5 L lab-scale jar at $25^{\circ}C$. The maximum alcohol production of the K-100 and F-50 reached levels of 135.0 mg/mL and 119.4 mg/mL, respectively. The pH values were in a range of 4.3-4.5. Total acidity was in a range of 0.47-0.60%. Organic acids and amino acids were analyzed in order to evaluate variations in its composition and content via HPLC analysis. Organic acids including lactic acid, citric acid, malic acid, and pyruvic acid, and 16 kinds of amino acids, including aspartic acid, were detected in all treatments. K-100 showed the highest amino acid contents, whereas F-50 exhibited the lowest amino acid contents. Volatile flavor components such as phenylethyl alcohol, isoamyl alcohol, 2-methylthiophane, isobutyl alcohol, and ethyl succinate were detected as a major component in all treatments, as determined via gas chromatography. The results of our sensory evaluation demonstrated that Yakju fermented by the FA776 fusant yielded more favorable results than S. cerevisiae KOY-1.

• The Journal of Engineering Geology
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• v.21 no.2
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• pp.163-178
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• 2011

A test borehole was drilled in the Cheongwon area to investigate the relationship between geochemical environment and the natural occurrence of radioactive materials (uranium and Rn-222) in borehole groundwater. The borehole encountered mainly biotite schist and biotite granite, with minor porphyritic granite and basic dykes. Six groundwater samples were collected at different depths in the borehole using the double-packed system. The groundwater pH ranges from 5.66 to 8.34, and the chemical type of the groundwater is Ca-$HCO_3$. The contents of uranium and Rn-222 in the groundwater are 0.03-683 ppb and 1,290-7,600 pCi/L, respectively. The contents of uranium and thorium in the rocks within the borehole are 0.51-23.4 ppm and 0.89-62.6 ppm, respectively. Microscope observations of the rock core and analyses by electron probe microanalyzer (EPMA) show that most of the radioactive elements occur in the biotite schist, within accessory minerals such as monazite and limenite in biotite, and in feldspar and quartz. The high uranium content of groundwater at depths of -50 to -70 m is due to groundwater chemistry (weakly alkaline pH, an oxidizing environment, and high concentrations of bicarbonate). The origin of Rn-222 could be determined by analyzing noble gas isotopes (e.g., $^3He/^4He$ and $^4He/^{20}Ne$).

• Korean Journal of Environmental Agriculture
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• v.18 no.3
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• pp.280-286
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• 1999

This studies were conducted to evaluate efficiency of microbial inoculator for active composting of food wastes. The Microbial inoculators used in this studies were purchased from different comparise to evaluate their effectiveness for composting of food waste in Korea. The number of bacteria growing at $30^{\circ}C$ in commercial inoculator collected were below $91.0{\times}10^8\;CFU/g$ which were counted from well cured compost made by animal manure. The number of bacteria in commercial microbial inoculator, such as FL, VP, B9, CM and GE were higher than that of composted at $50^{\circ}C$ or $60^{\circ}C$ of incubation temperature. Fungi were counted in GR, VP and B9 as over $10^3CFU/g$ at $30^{\circ}C$ of incubation temperature, while fungi of all the commercial inoculator collected could not grown at $50^{\circ}C$ and $60^{\circ}C$. Actinomycetes in most of the these had higher number($10^5CFU/g$) than that of compost : however, it was not detected at $60^{\circ}C$ incubation temperature from all the samples collected. The amount of carbon dioxid production was order to VP>HU>B9>GE>CM>Control>Compost in the lab scale composting test with or without inoculation of commercial inoculators, however, but the difference in carbon dioxide production was similar among each treatments. The effect of inoculation on composting parmeter such as pH changes, temperature increasing and change of chemicals properties were a little among each treatments, with or without inoculation of commercial inoculator in active composting of food waste. Using commercial inoculator did not show any statistical difference in food waste composting process under various condition such as pH changes, temperature changes, etc.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.2
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• pp.61-72
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• 2022

The present study was conducted to examine the effect of soybean silage as a crude protein supplement for corn silage in the diet of Hanwoo steers. The first experiment was conducted to evaluate the effect of replacing corn silage with soybean silage at different levels on rumen fermentation characteristics in vitro. Commercially-purchased corn silage was replaced with 0, 4, 8, or 12% of soybean silage. Half gram of the substrate was added to 50 mL of buffer and rumen fluid from Hanwoo cows, and then incubated at 39℃ for 0, 3, 6, 12, 24, and 48 h. At 24 h, the pH of the control (corn silage only) was lower (p<0.05) than that of soybean-supplemented silages, and the pH numerically increased along with increasing proportions of soybean silage. Other rumen parameters, including gas production, ammonia nitrogen, and total volatile fatty acids, were variable. However, they tended to increase with increasing proportions of soybean silage. In the second experiment, 60 Hanwoo steers were allocated to one of three dietary treatments, namely, CON (concentrate with Italian ryegrass), CS (concentrate with corn silage), CS4% (concentrate with corn silage and 4% of soybean silage). Animals were offered experimental diets for 110 days during the growing period and then finished with typified beef diets that were commercially available to evaluate the effect of soybean silage on animal performance and meat quality. With the soybean silage, the weight gain and feed efficiency of the animal were more significant than those of the other treatments during the growing period (p<0.05). However, the dietary treatments had little effect on meat quality except for meat color. In conclusion, corn silage mixed with soybean silage even at a lower level provided a greater ruminal environment and animal performances, particularly with increased carcass weight and feed efficiency during growing period.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.178-184
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• 1971

Samples of refined soybean oil were irradiated with lights from a 20-watt incandescent tungsten lamp, a 20-watt fluorescent daylight type lamp, a 20-watt low-pressure mercury vapor germicidal lamp, and direct sunlight for an experimental period of 147 days. Some samples were stored in a dark room throughout the period as a control. The peroxide values of all samples were measured every week. The induction period of the samples was arbitrarily taken as the time required for the samples to reach a peroxide value of 15. The induction period of the control was estimated at 198 days. Those of the samples irradiated with the incandescent light, the fluorescent light, the ultraviolet light, and the sunlight were estimated at 196, 119, 52 and 6 days, respectively. The sunlight showed by far the strongest prooxidant activity whereas the incandescent light showed the weakest but distinct prooxidant activity. The small temperature differences observed among the various samples throughout the experimental period did not seem to affect the oxidation rates of the irradiated samples in any significant way.

• Economic and Environmental Geology
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• v.54 no.4
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• pp.409-425
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• 2021

Carbon dioxide has been known to be a typical greenhouse gas causing global warming, and a number of efforts have been proposed to reduce its concentration in the atmosphere. Among them, carbon dioxide capture and storage (CCS) has been taken into great account to accomplish the target reduction of carbon dioxide. In order to commercialize the CCS, its safety should be secured. In particular, if the stored carbon dioxide is leaked in the arable land, serious problems could come up in terms of crop growth. This study was conducted to investigate the effect of carbon dioxide leaked from storage sites on soil fertility. The leakage of carbon dioxide was simulated using the facility of its artificial injection into soils in the laboratory. Several soil chemical properties, such as pH, cation exchange capacity, electrical conductivity, the concentrations of exchangeable cations, nitrogen (N) (total-N, nitrate-N, and ammonia-N), phosphorus (P) (total-P and available-P), sulfur (S) (total-S and available-S), available-boron (B), and the contents of soil organic matter, were monitored as indicators of soil fertility during the period of artificial injection of carbon dioxide. Two kinds of soils, such as non-cultivated and cultivated soils, were compared in the artificial injection tests, and the latter included maize- and soybean-cultivated soils. The non-cultivated soil (NCS) was sandy soil of 42.6% porosity, the maize-cultivated soil (MCS) and soybean-cultivated soil (SCS) were loamy sand having 46.8% and 48.0% of porosities, respectively. The artificial injection facility had six columns: one was for the control without carbon dioxide injection, and the other five columns were used for the injections tests. Total injection periods for NCS and MCS/SCS were 60 and 70 days, respectively, and artificial rainfall events were simulated using one pore volume after the 12-day injection for the NCS and the 14-day injection for the MCS/SCS. After each rainfall event, the soil fertility indicators were measured for soil and leachate solution, and they were compared before and after the injection of carbon dioxide. The results indicate that the residual concentrations of exchangeable cations, total-N, total-P, the content of soil organic matter, and electrical conductivity were not likely to be affected by the injection of carbon dioxide. However, the residual concentrations of nitrate-N, ammonia-N, available-P, available-S, and available-B tended to decrease after the carbon dioxide injection, indicating that soil fertility might be reduced. Meanwhile, soil pH did not seem to be influenced due to the buffering capacity of soils, but it is speculated that a long-term leakage of carbon dioxide might bring about soil acidification.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.223-229
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• 2022

This study was conducted to investigate the effect of packaging methods and sterilization treatment on storability and microbial control in paprika fruits. When treated with chlorine dioxide gas for 3, 6, and 12 hours and cold plasma gas for 1, 3, and 6 hours, and then packed in a carton box and stored in a 8 ± 1℃ chamber for 7 days, chlorine dioxide treated 12 hours and plasma treated 6 hours was prevented the development of E·coli and YM(yeast and mold). Accordingly, the control was treated with chlorine dioxide for 12 hours and plasma for 6 hours, packed using a carton box and 40,000 cc·m^-2·day^-1·atm^-1 OTR film (MAP), and stored in a 8 ± 1℃ chamber for 20 days. Fresh weight loss rate during storage was less than 1% in the MAP treatments, and the visual quality of the MAP treatments was above the marketability limit until the end of storage. There was no difference in the contents of oxygen, carbon dioxide, and ethylene in the film. In the case of firmness, the chlorine dioxide treatments was low, and the Hunter a^* value, which showed chromaticity, was highest in the Plasma 6h MAP treatment. Off-odor was investigated in the MAP treatments, but it was very low. The rate of mold growth on the fruit stalk of paprika was the fastest and highest in the chlorine dioxide treated box packaging treatments, and the lowest in the chlorine dioxide treated MAP treatments at the end of storage. The aerobic count in the pulp on the storage end date was the lowest in the plasma treated box packaging treatments, the lowest number of E·coli in the chlorine dioxide treated MAP treatments, and the lowest yeast & mold in the chlorine dioxide treated box packaging treatments. As a result, for the inhibition of microorganisms during paprika storage, it is considered appropriate to treat plasma for 6 hours before storage regardless of the packaging method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1209-1215
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• 2022

The selective catalytic reduction (SCR) is known as a very efficient method to reduce nitrogen oxides (NOx) and the catalyst performs reduction from nitrogen oxides (NOx) to nitrogen (N₂) and water vapor (H2O). The catalyst, which is one of the factors determining the performance of the nitrogen oxide (NOx) ruduction method, is known to increase catalyst efficiency as cell density increases. In this study, the reduction characteristics of nitrogen oxides (NOx) under various engine loads investigated. A 100CPSI(60Cell) catalysts was studied through a laboratory-sized simulating device that can simulate the exhaust gas conditions from the power generation engine installed in the training ship SEGERO. The effect of 100CPSI(60Cell) cell density was compared with that of 25.8CPSI(30Cell) cell density that already had NOx reduction data from the SCR manufacturing. The experimental catalysts were honeycomb type and its compositions and materials of V₂O₅-WO₃-TiO₂ were retained, with only change on cell density. As a result, the NOx concentration reduction rate from 100CPSI(60Cell) catalyst was 88.5%, and IMO specific NOx emission was 0.99g/kwh satisfying the IMO Tier III NOx emission requirement. The NOx concentration reduction rate from 25.8CPSI(30Cell) was 78%, and IMO specific NOx emission was 2.00g/kwh. Comparing the NOx concentration reduction rate and emission of 100CPSI(60Cell) and 25.8CPSI(30Cell) catalysts, notably, the NOx concentration reduction rate of 100CPSI(60Cell) catalyst was 10.5% higher and its IMO specific NOx emission was about twice less than that of the 25.8CPSI(30Cell) catalysts. Therefore, an efficient NOx reduction effect can be expected by increasing the cell density of catalysts. In other words, effects to production cost reduction, efficient arrangement of engine room and cargo space can be estimated from the reduced catalyst volume.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1655-1661
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• 2005

The present studies were designed to provide new information on fatty acid profiles of various muscles and adipose tissues of fattening horses in comparison with beef cattle and pigs. In the first study, the lipids were extracted respectively from subcutaneous, intermuscular adipose tissues, longissimus dorsi and biceps femoris muscles of fattening Breton horses (n = 8) with an average body weight of 1,124 kg. In the second study, the lipids were extracted from subcutaneous, intermuscular adipose tissues and longissimus dorsi muscle of fattening horses (n = 13), Japanese Black beef cattle (n = 5), Holstein steers (n = 5) and fattening pigs (n = 5). The fatty acids in the lipid samples were determined by gas chromatography after methylation by a combined base/acid methylation method. It was found that the lipids from horse subcutaneous and intermuscular adipose tissues contained more (p<0.05) polyunsaturated fatty acids (PUFA) which were mainly composed of linoleic acid (C18:2) and linolenic acid (C18:3) than those in the muscles. The weight percent of conjugated linoleic acids (CLA cis 9, trans 11) in lipids from biceps femoris muscle was 0.22%, which was higher (p<0.05) than that from the other depots. The horse lipids were higher (p<0.05) in PUFA but lower (p<0.05) in SFA and MUFA in comparison with those of the cattle and pigs. The percentage of C18:2 or C18:3 fatty acid in the horse lipids were respectively 2-8 fold or 5-18 fold higher (p<0.05) than those of the cattle and pigs. The percentages of CLA (cis 9, trans 11) in the horse lipids (0.14-0.16%) were very close to those of the pigs (0.18-0.19%) but much lower (p<0.05) than those of the Japanese Black beef cattle (0.55-0.94%) and Holstein steers (0.46-0.71%). The results indicated that the fatty acid profiles of lipids from different muscle and adipose tissues of fattening horses differed significantly. In comparison with that of the beef cattle and pigs, the horse lipids contained more C18:2 and C18:3 but less CLA.

• Environmental Analysis Health and Toxicology
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• v.14 no.1_2
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• pp.35-43
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• 1999

A number of disinfection by-products (DBPs) are formed as a result of the addition of chlorine into the public water supply and some of them have been suggested to cause adverse health effects on humans. However, the estimation of human ingestion exposure to each DBP has been performed simply by multiplying the concentration of a chemical in the cold tap water by the volume of water consumed during a given period of time. However, a questionnaire concerning water consumptions administered to sixty people residing in Chunchon showed that the volume of tap water consumed accounted for approximately 70% of the total volume of water consumed and that of heated water represented approximately 94% of tap water ingested. Heating durations for water-containing foods (e. g., soups and pot stews) and heated beverages (e. g., barley tea) were grouped into 10, 20, 30, and 35 minutes. Based on these time frames, an aluminum pot containing one liter of tap water was heated for the above respective time periods using a gas range to determine the variations of the concentrations of individual DBPs by heating. The pH and total residual chlorine were measured before and after heating. Collected water samples were carried to the laboratory and analyzed for eight DBPs and total organic carbon. Chloroform, bromodichloromethane, chloral hydrate, 1, 2-dichloro-2-propanone, 1, 1, 1-trichloropropanone, and dichloroacetonitrile were not detected following heating for 10 minutes and longer. The concentration of dichloroacetic acid (DCAA) was elevated with heating duration, resulting in the averages of 2.0, 3.1, 4.7, and 12 times the initial concentration, respectively, for 10, 20, 30, and 35 minute heating periods. On the other hand, the concentration of trichloroacetic acid (TCAA) decreased with heating duration, with 0.65, 0.40, 0.34, and 0.19 times lower than the initial concentration. Therefore, it is suggested that ingestion exposure to DCAA increases with heating duration but that ingestion exposure to TCAA decreases. In addition, while the amount of DCAA was elevated at the initial time periods (10 or 20 minutes) and then slowly decreased, that of TCAA was rapidly decreased. In conclusion, water-heating processes during cooking influence the concentrations of individual DBPs in the tap water, with lower levels for volatile DBPs and TCAA, and higher levels for DCAA. Therefore, concentration change needs to be taken into consideration in the estimation of human ingestion exposure to DBPs.