• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.283-289
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• 2016

The nutritional compositions and physicochemical properties of two aronia varieties (Viking and Nero) cultivated in Chungbuk were investigated. The proximate compositions of Nero and Viking powder were:13% moisture, 0.58% and 0.6% ash, 0.73% and 0.33% crude lipid, 5.47% and 6.51% crude protein, 15.65% and 16.15% crude dietary fiber, and 64.36 and 64.43% crude carbohydrate, respectively. The proximate contents of the aronia samples were not significantly different. Among the physicochemical properties, there was also no significant change in total anthocyanin and antioxidant activity. However, Viking had higher total polyphenol contents and ${\alpha}$-glucosidase inhibition activity than Nero. The mineral contents of Al, Fe, Mn, Mg, Ca, Na, K, Cu and Zn in the two aronias were determined. Cu and Zn were not detected in both varieties. With regard to Al, Na and K, Nero was higher than Viking, while Ca was higher in Viking than Nero. From the results, Viking could be suggested to be beneficial for food processing.

• Food Science and Preservation
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• v.23 no.5
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• pp.654-659
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• 2016

This study was designed to compare the quality characteristics of spray-dried (SD) and freeze-dried (FD) Pueraria thunbergiana extracts powder hot water extracts. Quality characteristics of the SD and FD powder including moisture content, color value, water absorption index, water solubility index, dynamic angle and antioxidant activities were evaluated. The moisture content of SD powder (1.50%) was lower than that of FD powder (2.92%). $L^*$ and $b^*$ values of SD powder was lower than of FD powder. The water absorption index was higher in FD powder (1.40) and water solubility index in SD powder (94.10%) was higher than that FD powder (90.69%). Dynamic angle of SD powder ($36.46^{\circ}$) was higher than that of FD powder ($33.30^{\circ}$). The DPPH radical scavenging activities of 5 mg/mL solution of SD powder and FD powder were 85.38 mg/mL, 59.38 mg/mL, respectively. And, the same trend was observed for the ABTS radical scavenging activities of the drying powder as that observed for their DPPH radical scavenging activities. There were relatively higher contents of phenolic compounds in SD powders than in FD powders. In conclusion, spray-dried Pueraria thunbergiana extracts showed the high WSI, polyphenol, DPPH and ABTS radical scavenging activities and low moisture content and dynamic angle than freeze dried powder.

• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.120-126
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• 2019

In this study, the quality characteristics and antioxidant activities of wet noodles added with seunggumcho (Angelica gigas N Leaf) powder at concentrations of 1, 2, 3, and 4%, respectively, were investigated. The moisture contents and pH of the samples showed a tendency to decrease with increasing amounts of seunggumcho powder. Texture measurement indicated that 'hardness,' 'springiness,' and 'chewiness' of the cooked noodle were the highest in the control group, and these parameters showed a tendency to decrease with increasing amounts of seunggumcho powder. The total polyphenol contents in wet noodles added with seunggumcho powder increased with increasing amounts of seunggumcho powder. 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was the lowest in the control group (10.85%) and highest in the 4% addition group (44.84%). ${\alpha}-Glucosidase$ inhibitory activity showed the lowest value in control group (1.17%), and increased with increasing amounts of seunggumcho powder. The sensory preference score was the highest for color, flavor, taste, and chewiness in the 2% addition sample. The findings of this study suggest the feasibility of seunggumcho added wet noodles as a health food with physiological benefits and provide evidence for introducing various health foods by adding seunggumcho.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.245-251
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• 2021

We determined the quality characteristics, acrylamide concentration, and antioxidant activity of Nurungji prepared using white rice, brown rice, gamma-aminobutyric acid (GABA) brown rice, oats, and barley. The moisture content of Nurungji prepared using white rice was the lowest (1.48%) and the highest (6.53%) was obtained in barley Nurungji. The brightness (L^*) of white rice Nurungji was the highest, whereas that of GABA brown rice Nurungji was the lowest. The acrylamide concentration was the lowest (37.24 ㎍/g) in white rice Nurungji and the highest (255.50 ㎍/g) in oats Nurungji. The levels of total polyphenol and total flavonoid were the lowest in white rice Nurungji and high in oats and GABA brown rice Nurungji. The antioxidant activity was higher in Nurungji prepared using oats, GABA brown rice, brown rice, and barley than that using white rice. It is necessary to select an appropriate grain when preparing Nurungji by considering the amount of acrylamide produced.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.405-417
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• 2022

The purpose of this study was to describe the photosynthetic features of Prunus maximowiczii and Prunus serrulate Lindl. var. pubescens (Makino) Nakai in response to drought stress. Specifically, we studied the effects of drought on photosynthetic ability and photosystem II activity. Drought stress (DS) was induced by cutting the water supply for 30 days. DS decreased the moisture contents in the soil, and between the 10th and 12th days of DS, both species had 10% or less of x., After the 15th day of DS, it was less than 5%, which is a condition for disease to start. We observed a remarkable decrease of maximum photosynthesis rate starting from 10th day of DS; the light compensation point was also remarkable. Dark respiration and net apparent quantum yield decreased significantly on the 15th day of DS, and then increased on the 20th day. In addition, the stomatal transpiration rate of P. maximowiczii decreased significantly on the15th day of DS, and then increased on the 20th day. Water use efficiency increased on the 15th day of DS, and then decreased on the 20th day. The stomatal transpiration rate of P. serrulate decreased significantly on the 20th day of DS, and then increased afterward, while its water use efficiency increased on the 20th day of DS, and then decreased afterward. These results indicate that the closure of stoma prevented water loss, resulting in a temporary increase of water use efficiency. Chlorophyll fluorescence analysis detected remarkable decreases in the functional index (PI_ABS) and energy transfer efficiency in P. maximowiczii after the 15th day of DS. Meanwhile, photosystem II activity decreased in P. serrulate after 20 days of DS. In addition, Ts-Ta, PI_ABS, DI_O/RC, ET_O/RC followed similar trends as those of the soil moisture content and photosynthetic properties, indicating that they can be used as useful variables in predicting DS in trees.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.140-145
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• 2000

This study was performed to investigate whether the earthworm cast could be reused as bulking agent in the whole processing of the food wastes using the earthworm. In addition, the growth conditions of microorganism lived upon earthworm lasts was investigated. Because the raw food wastes used in this experiment had low pH, and high moisture and organic matter contents, it was unsuitable to use as direct feeds to earthworm. However, when the food wastes were mixed with some earthworm cast, the mixtures were suitable to the feed condition and the growth environment of the earthworm. Therefore, it shows the possibility that the earthworm cast be reused as bulking agent for food wastes. In the microbiological investigation on earthworm cast, the bacteria showed most high density among the microbial species. And the microbial density showed higher under the mid-temperature than under high-temperature, and higher under the anaerobic than the aerobic condition. The drying methods of earthworm cast for the moisture adjusting, has no effect on microorganism growth whether natural or artificial drying. And the activity of enzyme presented more highly before the drying than after the drying.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.13-29
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• 2016

In this study, we analyzed the causes of major faults in the biogas plant through the case of gas engine failure when cogenerating electricity and heat using biogas as a fuel in the actual sewage treatment plant and suggested countermeasures. Hydrogen sulfide in the biogas entering the biogas engine and water caused by intermittent malfunction of the water removal system caused intercooler corrosion in the biogas engine. In addition, the siloxane in the biogas forms a silicate compound with silicon dioxide, which causes scratches and wear of the piston surface and the inner wall of the cylinder liner. The substances attached to the combustion chamber and the exhaust system were analyzed to be combined with hydrogen sulfide and other impurities. It is believed that hydrogen sulfide was supplied to the desulfurization plant for a long period of time because of the high content of hydrogen sulfide (more than 50ppm) in the biogas and the hydrogen sulfide was introduced into the engine due to the decrease of the removal efficiency due to the breakthrough point of the activated carbon in the desulfurization plant. In addition, the hydrogen sulfide degrades the function of the activated carbon for siloxane removal of the adsorption column, which is considered to be caused by the introduction of unremoved siloxane waste into the engine, resulting in various types of engine failure. Therefore, hydrogen sulfide, siloxane, and water can be regarded as the main causes of the failure of the biogas engine. Among them, hydrogen sulfide reacts with other materials causing failure and can be regarded as a substance having a great influence on the pretreatment process. As a result, optimization of $H_2S$ removal method seems to be an essential measure for stable operation of the biogas engine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1236-1241
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• 2013

This study was conduct in order to provide information on formula optimization, salinity, and water content for commercialization of traditional buckwheat Soksungjang. To do this, we determined quality characteristics such as total microbial flora counts, amino-type nitrogen content, total polyphenol content, antioxidant activity, and performed a sensory evaluation. The moisture contents showed a gradual decrease during the fermentation period. There was no significant difference in all samples. During 70 days of fermentation, the pH showed a similar trend starting at a pH of 6, and dropping sharply to 5.5, except Experiment C (15% buckwheat powder in the meju, 10% NaCl, and 130% water in the total Soksungjang). On the other hand, total acidity increased regularly, however, its ranges were various points in all samples. The microbial population was reduced by 1~3 log cycle in all samples during the fermentation period. The content of amino-type nitrogen showed a gradual increase during fermentation, ranging from 160 to 213 mg% after 70 days. No remarkable difference in total polyphenol content and antioxidant activity was observed in all samples. In sensory evaluation, Soksungjang with 30% (control) and 15% (Experiment C) buckwheat showed a significantly higher overall score.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1107-1113
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• 1998

This work was to study the potential use of germinated and microwave-vacuum-dried brown rite as a raw material for enzyme food. Brown rice was soaked in water at $15^{\circ}C$ for 2 days and then germinated at $25^{\circ}C$ for 4 days. The germin ated brown rice was then dried by different drying methods: microwave vacuum drying 1(drying only), microwave vacuum drying 2 $(drying{\rightarrow}crushing{\rightarrow}drying)$, hot air drying, vacuum drying and freeze drying. Each drier except freeze drier was set to maintain the sample temperature to be $60^{\circ}C$. During microwave vacuum drying 1 and 2 the sample reached $60^{\circ}C$ much faster (5 min) and was dried much faster (2 to 3 hrs for microwave vacuum drying 1 and 2 than the other drying methods. The initial drying rate of microwave vacuum drying was ten times faster than that of hot air drying. The microwave vacuum drying produced a dry sample of the highly retained enzymic activity, followed by freeze drying, vacuum drying and hot air drying.

• Food Science and Preservation
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• v.15 no.3
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• pp.340-346
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• 2008

This study investigated the microbial safety of apple snails and intermediate-moisture-content apple snail products subjected to various treatments, according counts of total bacteria, Escherichia coli, mold and yeast during storage at 4C Heating of raw apple snails at 95C for 5 min increased the storage period in relation to total bacteria, E. coli, mold and yeast-cell growth. Addition of 10% NaCl and 50% vinegar increased the microbial safety of apple snails. Microorganisms were not detected for 14 weeks in vacuum-packaged intermediate-moisture-content apple snail products stored at either 4C or 30C. These results suggest that heat treatment of raw apple snails, soaking in 10% NaCl and 50% vinegar solutions, and vacuum-packaging increases the shelf-life and microbial safety of apple snail products.