• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.597-605
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• 2019

In order to improve the adhesion of water-based adhesive, gemini type nonionic reactive surfactants were synthesized and applied to water-based adhesives. The surfactants were synthesized by using maleic acid and polyoxyethylene cetyl ether having different length of ethylene oxide and confirmed by FT-IR and $^1H-NMR$. Their appearance was light yellow wax. The cloud point of the compound was more than $78^{\circ}C$. The measured critical micelle concentration (c.m.c) was $1.0{\times}10^{-4}{\sim}7.0{\times}10^{-4}mol/L$ and surface tension at c.m.c was 25.9~32.0 mN/m. As the number of ethylene oxide increased, the emulsifying power was improved. The foaming height of each compound by Ross-Miles method was 1.4~4.5 cm. The synthesized surfactants was then used as an emulsifier in emulsion polymerization of water-based adhesives and its physical properties were evaluated. The solid contents of prepared adhesives was 59%. The average particle size and initial tackiness of the prepared adhesives were 164~297 nm and ball no. of 20~32, respectively. The peel strength was $1.8{\sim}2.1kg_f/mm$. The retention rate of adhesives viscosity was evaluated to 99% during 30 days. Therefore, synthesized gemini type nonionic reactive surfactants are expected to be applied as an emulsifier for the high adhesive force.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.321-328
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• 2021

Brownies containing whey powder (WP) with different levels of substitutions for wheat flour (0, 10, 20, 30, and 40% substitution for WP 0, WP 10, WP 20, WP 30, and WP 40, respectively) were prepared, and their properties were compared. Regarding appearance, the collapse of the sample surface noticeably started from WP 30. The moisture content was higher in samples containing WP than in the control (WP 0), and the weight of the brownie increased with WP content. As the WP amount increased, both the total and specific volumes of the brownies decreased. Regarding texture, a higher amount of WP resulted in a decrease in hardness, whereas adhesiveness increased significantly. The antioxidant activity also increased with increasing WP amount (from 35.28 to 51.47%). Regarding sensory characteristics, 20 or 30% WP in brownies increased mouth-feel properties, taste, and overall preference. Based on the above results, WP could improve the quality of brownies, and a substitution level of 20% could be the most appropriate.

• Journal of the Korea Society of Computer and Information
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• v.26 no.1
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• pp.19-26
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• 2021

Cultural assets excavated in historical areas have their own characteristics based on the background of the times, and it can be seen that their patterns and characteristics change little by little according to the history and the flow of the spreading area. Cultural properties excavated in some areas represent the culture of the time and some maintain their intact appearance, but most of them are damaged/lost or divided into parts, and many experts are mobilized to research the composition and repair the damaged parts. The purpose of this research is to learn patterns and characteristics of the past through artificial intelligence neural networks for such restoration research, and to restore the lost parts of the excavated cultural assets based on Generative Adversarial Network(GAN)[1]. The research is a process in which the rest of the damaged/lost parts are restored based on some of the cultural assets excavated based on the GAN. To recover some parts of dammed of cultural asset, through training with the 2D image of a complete cultural asset. This research is focused on how much recovered not only damaged parts but also reproduce colors and materials. Finally, through adopted this trained neural network to real damaged cultural, confirmed area of recovered area and limitation.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.179-184
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• 2022

In this study, edible films made of fish and mammalian gelatins were produced using heat pressing, and their physical properties were investigated. Transparent and smooth films were formed continuously and uniformly using a mixture of fish skin gelatin (FG) or mammalian gelatin (MG), glycerol, and water under the process of heat pressing at 90℃ and 20 MPa for 5 min. Heat-pressed FG films possessed lower light transmittance and tensile strength than heat-pressed MG films; however, their appearance, surface morphology, water vapor permeability, lightness, and redness were not different from those of heat-pressed MG films. Although heat-pressed FG films had lower tensile strength, they had a flatter and more uniform surfaces and demonstrated higher transparency and moisture barrier properties compared to the casted FG films. These results demonstrate the potential utility of heat pressing for the large-scale production of edible films using both FG and MG.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.646-655
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• 2022

This study was conducted to investigate the quality characteristics of Kimchi during fermentation and storage according to containers with native plant extract. The containers used in the experiment were antimicrobial polypropylene containers(KAPP) developed with the addition of native plant extracts, and it was tested by comparing the microbial changes and sensory characteristics of the existing commercial containers, such as polypropylene containers(KPP), stainless steel containers(KST), and porcelain containers(KPC). Change in total microbial cell were similar for each container. Coliform maintained the lowest level from 15 days after storage to 50 days. Leuconostoc spp. and Lactobacillus spp. showed a rapid increase in all four storage containers until the 15th day of storage and then decreased. The KAPP container maintained its highest level. The sensory evaluation was carried out on Kimchi optimal condition(storage 40 days). The sensory scores of KAPP were generally higher than those of other experimental samples in characteristics of appearance, odor, taste and overall preference. As a result, KAPP container has an excellent antibacterial effect as compared with the three commercially available storage containers, is effective for fermentation of lactic acid.

• Animal Bioscience
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• v.35 no.2
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• pp.281-289
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• 2022

Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk. Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4℃. Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period. Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.34-45
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• 2016

Global warming and climate change have been caused by combustion of fossil fuels. The greenhouse gases contributed to the rise of temperature between $0.6^{\circ}C$ and $0.9^{\circ}C$ over the past century. Presently, fossil fuels account for about 88% of the commercial energy sources used. In developing countries, fossil fuels are a very attractive energy source because they are available and relatively inexpensive. The environmental problems with fossil fuels have been aggravating stress from already existing factors including acid deposition, urban air pollution, and climate change. In order to control greenhouse gas emissions, particularly CO2, fossil fuels must be replaced by eco-friendly fuels such as biomass. The use of renewable energy sources is becoming increasingly necessary. The biomass resources are the most common form of renewable energy. The conversion of biomass into energy can be achieved in a number of ways. The most common form of converted biomass is pellet fuels as biofuels made from compressed organic matter or biomass. Pellets from lignocellulosic biomass has compared to conventional fuels with a relatively low bulk and energy density and a low degree of homogeneity. Thermal pretreatment technology like torrefaction is applied to improve fuel efficiency of lignocellulosic biomass, i.e., less moisture and oxygen in the product, preferrable grinding properties, storage properties, etc.. During torrefacton, lignocelluosic biomass such as palm kernell shell (PKS) and empty fruit bunch (EFB) was roasted under an oxygen-depleted enviroment at temperature between 200 and $300^{\circ}C$. Low degree of thermal treatment led to the removal of moisture and low molecular volatile matters with low O/C and H/C elemental ratios. The mechanical characteristics of torrefied biomass have also been altered to a brittle and partly hydrophobic materials. Unfortunately, it was much harder to form pellets from torrefied PKS and EFB due to thermal degradation of lignin as a natural binder during torrefaction compared to non-torrefied ones. For easy pelletization of biomass with torrefaction, pellets from PKS and EFB were manufactured before torrefaction, and thereafter they were torrefied at different temperature. Even after torrefaction of pellets from PKS and EFB, their appearance was well preserved with better fuel efficiency than non-torrefied ones. The physical properties of the torrefied pellets largely depended on the torrefaction condition such as reaction time and reaction temperature. Temperature over $250^{\circ}C$ during torrefaction gave a significant impact on the fuel properties of the pellets. In particular, torrefied EFB pellets displayed much faster development of the fuel properties than did torrefied PKS pellets. During torrefaction, extensive carbonization with the increase of fixed carbons, the behavior of thermal degradation of torrefied biomass became significantly different according to the increase of torrefaction temperature. In conclusion, pelletization of PKS and EFB before torrefaction made it much easier to proceed with torrefaction of pellets from PKS and EFB, leading to excellent eco-friendly fuels.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.120-132
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• 2015

The purpose of this study was to provide preliminary information for the utilization extension of Chinese artichoke(Stachys sieboldii Miq) as a functional food material. The effects of the addition of Chinese artichoke powder(0, 3, 6, 9, and 12%) in white bread formulation on phenolics content and antioxidant properties, and sensory analysis(seven-point hedonic test) were examined. The contents of total polyphenols(TPC), flavonoids (TFC), and tannins(TTC) in Chinese artichoke powder were $139.09{\pm}1.97mg\;GAE/g\;dw$, $74.33{\pm}2.69mg\;QE/g\;dw$, and $40.41{\pm}2.54 mg\;TAE/g\;dw$, respectively. As the amount of Chinese artichoke powder increased, the phenolics contents also significantly increased(p<0.001, p<0.001, and p<0.001 on TPC, TFC, and TTC, respectively), the highest TPC($104.27{\pm}0.13mg\;GAE/g\;dw$), TFC($71.03{\pm}1.75mg\;QE/g\;dw$), and TTC($8.76{\pm}0.12mg\;TAE/g\;dw$) were achieved in the white bread having the highest percentage of Chinese artichoke powder(12%). The $IC_{50}$ values of Chinese artichoke extract for 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid(ABTS) radical scavenging activities were 1.42 mg/mL and 1.57 mg/mL, respectively. Scavenging activities of DPPH and ABTS radicals of white bread were significantly increased according to the levels of added Chinese artichoke powder(p<0.001 and p<0.001, respectively). In the acceptance test, the white bread containing 9% Chinese artichoke powder was ranked significantly higher than the other groups according to all sensory parameters such as appearance, flavor, taste, texture, and the overall acceptability. Overall, Chinese artichoke enhanced white bread could be developed as an antioxidant-enriched bread with good sensorial properties.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.101-108
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• 2005

Because the stone cultural properties located outdoors, they have been altered and deteriorated in external appearance due to environmental factors such as acid rain, extreme change in temperature, and salts. Damage to stone cultural properties is accelerated particularly due to recent industrial development and environmental pollution. An experimental study was conducted to evaluate the effect of environmental contaminants on the weathering of granite. And as part of the developing of conservation method, $TiO_2$ catalyst was prepared and tested. When fresh granite was dipped into the salt and acid solutions, dissolution rate of eight minerals (Si, Mg, Ca, Na, K, Fe, Mn, Al) are abruptly increased at initial stage of reaction and then increased steadily until 100 cycles. After salt and acid solution experiments, the mineral compositions of the granite surface were lower then that of the fresh granite and density of the weathered granite was steadily decreased from $2.60\;g/cm^3$ to $2.56\;g/cm^3$, but Poissions ratio and absorption ratio were slightly increased. It was expected at stone cultural assets could be weathered by salts and acid rain. In the case of $TiO_2$ was coated to the granite, the dissolution rate of minerals and absorption ratio of $TiO_2$ coated granite were decreased. Therefore, the $TiO_2$ coating method tested in this study considered to be a viable method to assist in the conservation of stone cultural properties from environmental contaminants.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.438-447
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• 2016

This study was conducted in order to investigate the physiochemical properties and antioxidative activity of red ginseng manufactured using the high temperature high pressure (HTHP) process, which is faster and simpler than the conventional process. According to increasing the steaming temperature, pressure and time, the content of minor non-polar ginsenosides, such as Rg3, Rk3, Rh4, Rk1 and Rg5 gradually increased. Also, the contents of acidic polysaccharide, total phenolic compounds and maltol gradually increased. Based on the results of the physiochemical properties and appearance quality, the optimum conditions of HTHP process were estimated as $140^{\circ}C$, $3kg/cm^2$ in 20 min. The total phenolic compounds and maltol contents of the HTHP process red ginseng (1.0% and 2.49 mg%, respectively) were higher than those of conventional red ginseng (0.23% and 0.60 mg%, respectively). In addition, the antioxidative activity was investigated using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-aziono-bis(3-ethylbenzthiazoline-6-sulfonic acid)) radical scavenging activity. DPPH and ABTS radical scavenging activities of HTHP process red ginseng increased by 3.4 and 3.6 folds, respectively, compared with conventional red ginseng. In addition, total phenolic compounds and maltol contents, as well as the antioxidant activity of the HTHP process red ginseng were similar to black ginseng. The present results suggest that the HTHP process is available for the development of value-added red ginseng products.