• Architectural research
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• 제13권1호
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• pp.25-32
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• 2011

The purpose of this research is to investigate the effect of specific hydration reaction on the stiffening process of cement paste. The cement compositions are manipulated to cause specific hydration reactions (secondary gypsum and syngenite formation) responsible for false set, and the relationship between specific hydration reactions and the flow and stiffening behavior of cement paste were investigated using modified ASTM C 403 penetration resistance measurement and oscillatory shear rheology. X-ray powder diffraction (XRD) was used for the phase identification associated with premature stiffening of cement paste. Differential thermal analysis (DTA) and thermogravimetric analysis (TGA) were used for verification of syngenite formation. From the results, both secondary gypsum and syngenite formation caused faster stiffening and set. The amount of syngenite produced during 1 hour hydration was approximately 1 % of total mass of the cement paste, but cement paste with syngenite formation showed significantly accelerated stiffening behavior compared to normal cement paste.

• Journal of Microbiology and Biotechnology
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• 제3권4호
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• pp.277-284
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• 1993

We confirmed the character impact compounds of the flavors of the soybean paste manufactured with the traditional and improved Meju, respectively, by using the following methods: gas chromatography (GC), sniffing tests and GC-mass. The soybean paste made with the traditional Meju had 12 compound groups that smelled like the soybean paste flavor, whereas the soybean paste made with the improved Meju had 7 compound groups of soybean paste flavor smell. We were easily able to determine that there is a difference of soybean paste flavor compounds between the soybean pastes made with either the traditional or the improved Mejus because the two soybean paste flavors are very different from each other.

• 동아시아식생활학회지
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• 제20권5호
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• pp.713-719
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• 2010

The objective of this study was to evaluate the quality characteristics of Dasik containing different levels of jujube paste (0%, 60%, 70%, 80%, 90%). Moisture composition of the paste ranged from 19~29% As the content of jujube paste increased, the lightness (L) and yellowness (b) decreased while redness (a) increased In the texture profile analysis, as the content of jujube paste in Dasik content increased, the hardness decreased Cohesiveness and springiness did not show significant differences according to amount of jujube paste. The results of the sensory evaluation show that sweetness, bitterness, and overall acceptability were the highest in Dasik containing 80% level jujube paste.

• Preventive Nutrition and Food Science
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• 제10권2호
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• pp.145-150
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• 2005

This study was carried out to examine the properties of sample amount and storage conditions on the accumulated pulsed photostimulated luminescence (PPSL) signals of soybean paste powder. Difference amounts (0.1, 0.5 and 1 g) of soybean paste powder samples stored in normal room and darkroom conditions were measured. The PPSL signals of the soybean paste powders significantly increased with irradiation dose up to 10 kGy. The PPSL signals of irradiated soybean paste powder samples decreased with increasing storage periods. The decay rates were similar to regardless of storage conditions and sample amount. The PPSL signals of the irradiated soybean paste powder measured for 120 s were higher than those measured for 60 s. These results indicated that although the PPSL signal of all soybean paste powder samples decreased with increasing storage time, detection of irradiated samples was still possible after 12 months of storage regardless of sample amount and measurement times in both normal room and darkroom conditions.

• 한국식품과학회지
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• 제26권5호
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• pp.609-615
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• 1994

Aspergillus oryzae, Bacillus natto균주와 재래식 메주를 사용하여 담금한 재래식 된장, 고오지 된장, 나토 된장, 고오지와 나토의 혼용된장의 질소성분과 아미노산을 분석한 결과는 다음과 같다. 아미노산성 질소는 숙성 90일에 $271{\sim}868\;mg/100g$으로 최대치를 보였으며 시험된 장별 함량은 고오지 된장, 재래식 된장, 고오지-나토 된장, 나토 된장의 순으로 높았다. 총 아미산은 Glutamic acid, Aspartic acid가 양적으로 많았고 함량은 고오지 된장에서 높았으나 시험 된장간의 함량 차이는 크지 않았다. 유리 아미노산은 시험된장에 따라서 다소 차이는 있지만 Glutamic acid, Tyrosine, lysine Aspartic acid 등이 비교적 많이 검출 되었다. 90일 유리 아미노산 총량은 고오지 된장이 3,339.5 mg/100g로 가장 높았고, 다음이 재래식 된장, 고오지-나토 된장, 나토 된장의 순이었다. 총 아미노산에 대한 유리 아미노산의 비율은 45일에는 $3.3{\sim}19.8%$였으나 90일에는 $10.98{\sim}25.1%$로 증가 되었고 90일의 총 아미노산에 대한 유리 아미노산의 비율은 재래식 된장, 고오지 된장 고오지-나토 된장, 나토 된장의 순으로 높았다. Methionine, Histidine 등은 총 아미노산에 대한 유리 아미노산의 비율이 높으나 Glutamic acid, Aspartic acid 등은 낮았다. 본 실험의 결과로 볼 때 유리 아미노산 및 총 아미노산에 대한 유리 아미노산의 비율이 높은 재래식이나 고오지 된장이 된장 숙성에 유리한 것으로 생각된다.

• 한국식품영양학회지
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• 제31권1호
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• pp.43-51
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• 2018

This study was conducted to investigate the quality of pumpkin paste added with different starches during storage at $4^{\circ}C$ for 8 days. Pumpkin paste was evaluated for pH, carotenoid, syneresis, color values, texture, and sensory characteristics. The properties of the pumpkin paste were studied on three different starches (CON: control, MCP: cow pea starch, MMB: mung bean starch, and MSP: sweet potato starch). The initial pH of the pumpkin paste with starches were 6.13~6.16. The pH of pumpkin paste increased as the starches added increased. The carotenoid content of CON was higher in the pumpkin paste processing. The change of syneresis significantly increased with the storage period, and the amount of change of MCP and MMB added with starch was smaller than CON without the added starch. The Hunter's L-values of the pumpkin paste increased, whereas the a- and b-value decreased as the amount of starches added increased. The results of the textural analysis showed that the hardness of MCP and MMB was different from that of other pumpkin paste, showing a lower value such as 38.26 g, 38.93 g, while CON and MSP was 40.43 g and 42.49 g, respectively. A sensory evaluation indicated that starches could enhance the overall texture characteristics of pumpkin paste. In terms of the overall acceptance of the pumpkin paste, the experimental group with MCP scored the best.

• 한국식품영양과학회지
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• 제29권5호
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• pp.807-813
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• 2000

One hundred fifty grams of Korean fermented soybean paste and hot pepper-soybean paste were packaged in glass jar of 232 mL and Sotred at 5, 13, 22 and 30℃. During the storage, the changes in their microbial flora and quality attributes were monitored. Carbon dioxide production rate from the stored pastes were also determined from initial change of CO₂concentration in headspace of the pack. Hot pepper-soybean pate showed much higher CO₂ production rate higher dependence of CO₂ production on temperature compared to soybean paste. Total aerobic bacteria count and lactic acid bacteria count did not change significantly through the storage. Yeast count in soybean paste decreased slowly after initial uprise while that of hot pepper-soybean paste steadily decreased. Surface color of hot pepper paste changed to dark red with slight decrease in 'L' value and slight increase in 'a' and 'b' values, whereas any significant color change was not observed in soy paste. Titratable acidity increased with time with higher increase in soybean paste, but pH stayed at constant level for both pastes. All the rates of quality change were higher with higher temperature. Pressure buildup due to CO₂ production needs to be considered first in designing the packages of the fermented pastes before their color changes and other chemical quality changes.

• 한국식품영양과학회지
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• 제24권6호
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• pp.917-924
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• 1995

재리식 메주, 고오지, 나토 메주, 고오지와 나토의 혼용 메주로 담금한 된장의 일반성분 유리당 및 지방산 조성은 다음과 같다. 조단백질은 10.3~14.6%로 재래식 메주 사용의 된장과 나토된장이 높았고 고오지 된장이 낮았다. 수분은 46.9~54.5% 범위로 숙성과정 중 다소 증가하였고 나토된장이 많았다. 에틸알코올은 숙성 75일 까지는 고오지와 나토의 혼용 된장에서 높았으나 숙성 90일에 고오지 된장이 2.8%로 최대치를 보였다.총당과 환원당은 숙성기간의 경과에 따라 감소하였으며 이들 당 함량은 고오지 된장, 고오지와 나토의 혼용된장, 재래식 메주사용의 된장, 나토된장의 순으로 높았다. 된장의 유리당으로 glucose, galactose, mannose, arabinose가 동정되었으며 이중 glucose, galactose가 타유리당 보다 많았다. 숙성 90일 후에는 glucose나 총 유리당 함량은 재래식 메주로 담근 된장에서 높았고, galactose는 고오지 된장에서 높았다. 된장의지방산으로 palmitic, stearic, oleic, linoleic, linolenic, arachidonic acid가 분리되었고, 이 중 oleic acid가 38.5~46.9%로 시험된장 모두에서 많은 비율로 나타났다. 그러나 숙성기간이나 시험구에 따른 지방산 조성 비율은 뚜렸한 차이가 없었다.

• Computers and Concrete
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• 제16권6호
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• pp.847-864
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• 2015

This study aimed to develop models of sulfate diffusion and ettringite content profile in cement paste for the predication of the damage behavior in cement paste subject to external sulfate. In the models, multiphase reaction equilibrium between ions in pore solution and solid calcium aluminates phases and the microstructure changes in different positions of cement paste were taken into account. The distributions of expansive volume strain and expansion stress in cement paste were calculated based on the ettringite content profile model. In addition, more sulfate diffusion tests and SEM analyses were determined to verify the reliability and veracity of the models. As the results shown, there was a good correlation between the numerical simulation results and experimental evidences. The results indicated that the water to cement ratio (w/c) had a significant influence on the diffusion of sulfate ions, ettringite concentration profile and expansion properties in cement paste specimens. The cracking points caused by ettringite growth in cement paste specimens were predicted through numerical methods. According to the simulation results, the fracture of cement paste would be accelerated when the specimens were prepared with higher w/c or when they were exposed to sulfate solution with higher concentration.

• 한국식품영양과학회지
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• 제23권6호
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• pp.980-985
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• 1994

We investigated the quality of soybean paste(Doenjang) fermented by BAcillus brevis. The results obtained were as follows : soybean paste fermented by Bacillus brevis had alkaline pH and yellow ochre color. Dextrinizing activity was about 98 D.P. unit from 5th to 25th day of fermentation at 3$0^{\circ}C$ and after that day somewhat decreased . Saccharifying activity was respectively 6.1, 7.2, 6.8, 6.4 S.P. unit on 5, 15, 25 and 35th day of fermentation. Protease activity suddenly increased after 15th day of fermentation and was 250, 275, 299 unit on15, 25, 35 th day of fermentation , respectively. The most abundant free amino acid was found to be glutamic acid (561.8mg%) in soybean paste fermented by Bacillus brevis. In case of free sugar and non-volatile organic acid, fructose and oxalic acid showed highest content of 10.25mg% on 25th day and 12.20mg% on 15th day. The contents of free amino acids, free sugars, organic acids in soybean paste fermented by B.brevis were most abundant after 25 days of fermentation and this results were similar to that of traditional soybean paste. The odor of soybean paste fermented by Bacillus brevis was improved to be a nice soybean paste odor on 25th day of fermentation. However, sensory evaluation value of the taste of it decreased after 10 th day of fermentation.