• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.615-623
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• 1998

The garlic juices were extracted and concentrated by heating at $90^{\circ}C$, by using a rotary vacuum evaporator at $45^{\circ}C$, or by freezing at $-50^{\circ}C$ until the volume was reduced to 70% of the original volume. The concentrated juices were kept at $4^{\circ}C\;or\;25^{\circ}C$ for 60 days and the changes of bacteria and color were monitored every 10 days. Flavors of the raw garlic juices, concentrated garlic juices, and garlic powder by hot-air drying were analyzed monthly using GC and GC/MS. The CFUs/mL of mesophilic and psychrotrophic bacteria in the garlic juice concentrated at $90^{\circ}C$ were lower about 1 to 2 log cycles than those of other concentrated juices. Hunter L, a, and b values in the raw garlic raw juice and the juice concentrated at $-50^{\circ}C$ significantly increased at the beginning of storage, in particular, when they were stored at $25^{\circ}C$. The garlic juice concentrated at $45^{\circ}C$ showed relatively low L value but the juice concentrated at $90^{\circ}C$ showed high a value. The main peaks in chromatograms of volatile components identified by GC/MS were 3,3'-thiobis-1-propene, di-2-propenyl disulfide, 3-(methylthio)-1-propene in the raw garlic juice and the concentrated juices, and the juices concentrated at $45^{\circ}C\;or\;-50^{\circ}C$ showed relatively high preservation of garlic flavor.

• Transactions of the KSME C: Technology and Education
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• v.1 no.1
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• pp.69-73
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• 2013

This study is about the secondary concentration technology using electrodialysis process for minimum discharge and maximize recovery ratio from seawater desalination by reverse osmosis process. The experimental method adopted the constant voltage driving method and, concentrated/desalination volume capacity ratio changes, voltage changes and electrolyte types. Multi-ion membrane is used, aiming to derive conditions to minimize the TDS concentration of desalination water, to minimize the volumes of secnodary concentraion water and minimizing the power efficiency. The results of this study are as follows. The optimal ratio of concentraion/desalination volume is 1:5, the final TDS concentration of desalinated water is 5.32g/l, the final secnodary concentrated water salinity is 17.07% and electric energy demands of desalinated water is $16.74kWh/m^3$.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.188-194
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• 2003

천마식품가공시 기초자료로 활용될 수 있는 천마 추출농축액의 리올로지 특성을 조사하였다. 천마의 열수 및 50% 에탄올 추출물운 각각 5, 10, 15, 및 20 Brix와 10, 20, 30, 40 및 50 Brix로 농축하여 제조하였다. 열수 및 50% 에탄올 농축액의 정상유동특성과 동적점탄성을 조사하였다. Power law model로 구한 n에 의하면 모든 열수 농축액들은 전형적인 의가소성$(n=0.484{\sim}0.802)$유체의 흐름특성을 보였고, 50% 에탄올 농축액들은 뉴튼유체$(n=0.875{\sim}1.078)$에 가까운 흐름특성을 나타내었다. 열수 및 50% 에탄올 농축액의 ${\eta}_{app}$는 온도가 증가함에 따라 감소하는 경향을 나타내었다. Herschel-Bulkley model에 의한 열수 및 50% 에탄올 농축액의 C는 각각 $0.030{\sim}1.255$ Pa와 $0.007{\sim}0.065$ Pa이었다. ${\eta}_{app}$에 대한 온도 및 농도의 영향은 arrhenius식으로 해석하였다. 열수 및 50% 에탄올 농축액의 $E_a$는 농도가 증가함에 따라 각각 $3.340{\sim}4.620{\times}10^3\;J/mol{\cdot}kg$과 $1.6289{\sim}18.6699{\times}10^3\;J/mol{\cdot}kg$의 범위로 나타났다. 진동수(angular frequency, ${\omega}$)가 증가할수록 저장탄성률(storage modulus, G#)과 손실탄성률(loss modulus, G@)은 일반적으로 증가하는 경향을 나타냈다. 50% 에탄올 농축액의 경우 모든 진동수에서 G#이 G@보다 높게 나타나 전형적인 저분자용액의 흐름특성을 보였다. 그러나 열수농축액의 경우 G@이 G#보다 높았고 0.5 rad/sec에서 교차점을 형성하였으며 전형적인 고분자 용액의 흐름특성을 나타내었다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.229-230
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• 2001

휘발성이 큰 많은 종류의 유기물질들이 대기오염물질로서 존재하고 있어 이에 대한 환경규제가 강화되고 있다. 이러한 유해 유기물질들은 ppb의 매우 낮은농도에서도 유해성을 갖고 있어 이를 분석하기 위한 공인된 분석방법은 모두 농축과정을 사용하고 있다. 캐니스터을 이용한 저온농축법과 흡착관을 이용한 농축법이 일반적으로 사용되고 있는데 이러한 농축방법은 고가의 농축장치를 필요로 하므로 이러한 유해물질의 측정이 보편화되는데 장애가 되고 있다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 1995.04a
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• pp.60-61
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• 1995

유업에 있어서 분리막의 이용은 에너지 절약면에서 많은 관심을 끌고 있다. 현재, 분리 농축에 있어서는 증발 또는 진공 농축법이 주로 이용되고 있다. 그러나 이들은 대량의 에너지를 사용하고 있기 때문에 에너지 손실이 크며, 특히 열변성이 일어나는 문제점이 있다. 이러한 문제의 해결책으로서 관심을 끌게 된것이 막분리 공정을 응용한 농축공정이다.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.263-270
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• 2011

This study was performed to acquire processing and reducing factors of difenoconazole during ginseng processing, and to establish the maximum residue limits of ginseng and its commodities. Difenoconazole was used in two fields (Wonju and Icheon) containing 6 year old ginseng plants. The amount of residue at Wonju and Icheon were

• Culinary science and hospitality research
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• v.20 no.1
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• pp.143-158
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• 2014

This study was conducted the physicochemical and sensory characteristics of Bulgogi sauce added with concentrated Curcuma longa L.. Increasing the amount of concentrated Curcuma longa L. in the Bulgogi sauce tended to increase the pH values, lightness(L), redness(a) and yellowness(b) values. It also tended to increase DPPH radical activity, but total polyphenol contents of Bulgogi sauce added with concentrated Curcuma longa L. were not significantly different among all the samples. In sensory evaluation, Bulgogi sauce added with 10% concentrated Curcuma longa L. had an excellent score in sensory taste, but Bulgogi sauce added with 20% concentrated Curcuma longa L. had an excellent score in overall preference. Seasoned roasted beef addition with 20% concentrated Curcuma longa L. had an excellent score in sensory preference. Therefore, this results suggest that 20% concentrated Curcuma longa L. should be applied to Bulgogi sauce for high sensory preference.

• Culinary science and hospitality research
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• v.18 no.3
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• pp.239-251
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• 2012

This study was conducted to examine the physicochemical and sensory characteristics of teriyaki sauce added with jujube concentrate. Brix of teriyaki sauce groups added with jujube concentrate were higher than the control. Increased amount of jujube concentrate in the teriyaki sauce tended to increase the viscosity, lightness(L), redness(a) and yellowness(b) values while it tended to decrease pH, the salinity and free amino acid contents. In sensory evaluation, teriyaki sauce added with 20% jujube concentrate had excellent score in sensory preference. Total viable cells of teriyaki sauce by the storage period, not found in control and teriyaki sauce added with jujube. Based on the results, 20% should be recommended as the optimum level of jujube concentrate to be added for the preparation of teriyaki sauce.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.32-36
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• 2009

The physical properties of freeze-dried Aloe vera gel powders were examined according to the influence of the concentration degrees of the gel solutions as raw materials during freeze-drying. As a pre-treatment prior to freeze-drying, the gel solutions were vacuum-concentrated at three concentration levels (g water/g solids): high (H), 76; medium (M), 119; and low (L), 159. The water contents of the three powder samples were almost the same. For their viscosity measurements, non-Newtonian fluid behavior with shear thinning was observed in samples H and M, whereas Newtonian liquid behavior was found in sample L. In electrical conductivity measurements, sample H showed the highest conductivity upon dissolving the powder in water. For their water sorption isotherms, sample H was analyzed to have the least amount of bound water. Finally, it was determined that the degree of concentration caused only slight differences in the physical properties of freeze-dried Aloe gel powders.

• Korean Journal of Food Science and Technology
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• v.18 no.3
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• pp.204-209
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• 1986

The functional properties of defatted silkworm larvae flour and protein concentrate have been compared with those of soybean. The protein contents of soybean and silkworm larvae protein concentrate were 70.3% and 84.1%, respectively. The solubility of silkworm larvae protein concentrate was lower than that of soybean protein at various pH tested. However, silkworm larvae protein concentrate showed better fat absorption, poorer water absorption and overall higher bulk density than soybean protein. The silkworm larvae protein concentrate showed higher emulsifying capacity and stability, but showed lower foaming capacity and stability than soybean protein. Silkworm larvae protein concentrate showed highest viscosity among various protein products at all concentrations and reached the highest viscosity at 5${\sim}$7% protein concentration. Therefore, high emulsification properties of silkworm larvae protein concentrate will be a good protein source when it is added to emulsified food.