• Applied Biological Chemistry
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• v.35 no.1
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• pp.6-9
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• 1992

The browing, pyruvate content of sliced garlic during the drying in terms of drying temperature and sulfiting treatment were investigated. Sulfiting reduced the browning of garlic slices and prevented the reduction of pyruvate content against heat during the drying. Contents of pyruvate were decreased as the increase of drying temperature. Sulfiting treatment killed the microorganisms of sliced garlic products during the drying.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.303-310
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• 2008

This study was performed to verify the effects of encapsulation against oil oxidation. Thiobarbituric acid (TBA) values of samples were compared during storage at $60^{\circ}C$, indicating that the encapsulated avocado oil had lower TBA values than the free avocado oil. Microcapsules consisting of a whey protein isolate (WPI)-only wall system had slightly improved oxidative stability; however, spray-dried particles containing a high proportion of maltodextrin (MD) clearly offered better protection from oxidation than the other forms of encapsulation. The chlorophyll (Chl) content of the encapsulated avocado oil was higher than that of the free oil sample. When compared to the control, all wall systems protected the change of the chlorophyll content storage. No large differences were observed between the encapsulated powders according to the various wall materials. The color of the encapsulated oil changed from green to yellowish-green, indicating the formation of pheophytin from chlorophyll. The yellowish color of the oil correlated with a reduced total Chl content. In conclusion, encapsulation with spray drying for avocado oil could lead to improved stability during storage with respect to oxidation and the preservation of chlorophyll.

• Food Science and Industry
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• v.49 no.2
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• pp.63-70
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• 2016

대부분의 산채는 한 계절에만 생산되므로 연중 공급될 수 있는 건조 상태로 유통된다. 건조 산채에 필요한 제품화 기술로는 재수화시간 단축기술, 간편 즉석 산채와 즉석 조리 산채의 제품화 기술 등이다. 식품소재로의 응용분야 확대를 위해서는 산채를 미분화하여 일반식품소재화 하는 방법이 적합하다. 그러나 전분함량이 낮은 산채류는 분쇄력이 가해지기 어려워 공업 규모에서의 미분말 제조가 곤란하고 비용적인 문제로 용도가 제한된다. 따라서 산채의 식품소재화 공정에서 중요한 핵심기술은 분쇄이므로 저비용에서의 미분말 제조기술 개발이 필요하다.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.103-111
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• 2009

Moisture is one of the important design factors that affects to the changes of physical properties and air permeability in the composting matrix. This study examines the effects of moisture during the wetting and drying procedure on physical properties like bulk density, particle size, free air space and air permeability in the sawdust used as the bulking agent in composting process. During both procedures of wetting and drying of the water, with increasing moisture content, bulk density and particle size increased, but FAS decreased. In the range of near 40 to 60% moisture content on a wet basis, particle size and FAS in wetting procedure were larger and higher than those in drying procedure. During wetting procedure, pressure drop continuously decreased ranging from near 20 to 60% moisture content, despite of decreasing FAS as a consequence of increasing moisture, and then over the range of 60% moisture content, pressure drop rapidly increased to the saturated moisture condition while the pore space was filled with the water. On the other hand, during drying procedure, pressure drop decreased from the saturated condition to 40% moisture content. In the recommended range of 50 to 60% moisture content for composting operation, pressure drop in wetting procedure were lower than in drying procedure. For the enhancement of the air permeability in the composting matrix, the wetting procedure was proper than the drying procedure, and the optimum moisture content for the efficient composting operation was appeared to be near 60%.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.307-312
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• 1989

Internal mass transfer during osmotic dehydration of carrots in sugar solutions was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration and blanching on browning reaction of vacuum dried carrots(3% MC: wet basis) was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in first 4 min and then levelled off. The rate of sugar gain and molality changes on temperature was significant in lower concentration$(20^{\circ}\;Brix)$ compared to higher concentration$(60^{\circ}\;Brix)$. The changes of rate parameter were affected by concentration than by temperature of sugar solutions. Moisture loss during osmotic dehydration using a sugar solution $(60^{\circ}\;Brix,\;80^{\circ}C)$ with 20min immersion time was 55.7%. Effect of osmotic dehydration and blanching before vacuum dried to 3% MC(Wet basis) on browning reaction was significant. Minimum browning reaction during vacuum drying was carried out using pretreatments such as osmotic dehydration in sugar solution$(40^{\circ}\;Brix,\;80^{\circ}C)$ with 16 min immersion time(O.D.=0.09) and blanching with 12 min immersion time at $80^{\circ}C$(O.D.=0.31) compared to control(O.D.=1.59).

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.245-251
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• 2001

This research was conducted to study the changes in physical characteristics of mushrooms (Agaricus bisporus) as influenced by drying methods. Samples were dried using either hot air drying, vacuum drying, or freeze drying and changes in the color, browning index, hardness and rehydration rate were evaluated by response surface methodology. Hot air drying resulted in the fastest drying of sample as compared to other methods. The rate of drying was most affected by the environmental temperature rather than air velocity or vacuum pressure. The overall color difference increased as the temperature and air velocity increased. The overall color changes of the freeze dried samples were minimal as compared to those of fresh mushrooms. The hot air dried samples showed the greatest changes in the overall color, browning index as well as hardness. The freeze dried samples showed the best rehydration characteristic and maintained the best overall quality after drying.

• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.42-47
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• 2024

Limonene was separated from waste citrus peels by a vacuum drying process with a venturi, and bioethanol was produced from dried citrus peels. Vacuum drying using venturi was very effective in removing moisture and limonene compared to hot air drying and natural drying. Citrus peels prepared by venturi vacuum drying were the most suitable for ethanol fermentation. The moisture and limonene content of the citrus peels dried for 15 hours were 17.0% and 3.2%, respectively. By venturi vacuum drying, essential oil containing limonene and floral water were obtained, respectively. The amount of essential oil separated by venturi vacuum drying was 4.21 mL essential oil/kg citrus peel, 79.9% of the separated essential oil was limonene.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.3
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• pp.347-352
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• 1999

The finite element formulation and simulation of drying process for ceramic electric insulators are investigated. The heat and moisture movements in green ceramics caused by the interaction of temperature gradient, moisture gradient, conduction, convection and evaporation are considered. The variations of temperature and moisture not only change the volume but also induce the hygro-thermal stress. The finite element formulation for solving the temperature and moisture distributions as well as the associated hygro-thermal stresses is derived. Using the computer code developed, the drying process of a ceramic electric insulator is simulated. Temperature distribution, moisture distribution, hygrothermal stress and deformed shape during the drying process are predicted.

• Journal of Korean Society of Steel Construction
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• v.16 no.1 s.68
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• pp.135-144
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• 2004

Since Modern bridges have a tendency to make the spans continuous and longer, the effect of concrete shrinkage and creep is very important and must be evaluated appropriately for the durability and safety of steel-concrete composite bridges. However, highway design specification in current use prescribes $180^{1\;2}$ as the final shrinkage strain. which is for less value than one resulted from many experimental researches and cause some problems in the construction of composite bridges due to the understimation of shrinkage strain. Thus, in this paper nonlinear analysis with time-steps applying the CEB-FIP(90) provision have been conducted for plate girder bridge, box girder bridge and Preflex beam bridge and the linear equivalent shrinkage strain for the design of composite bridges. which produces the stress equal to the values from the nonlinear analysis, has been calculated by comparing the results with the values following highway design specification. The results yield appropriately double values than $180^{1\;2}$ which highway design specification prescribes.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2004.07a
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• pp.42-42
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• 2004

본 연구에서는 고추(김치)의 색깔을 유지시키고 제조시 원가를 절감하며, 영양소의 파괴를 보다 최소화할 수 있는 방법으로 고추의 수분을 60~70% 정도로 건조 이를 -4$0^{\circ}C$에서 급속냉각하여 -2$0^{\circ}C$ 정도에서 장기간 저장하면서 김치제조에 이용하면 색깔이 좋은 양질의 김치를 생산, 소비자에게 공급할 수 있다. 김치제조시 부원료인 홍고추를 반건조하여 수분의 함량을 측정한 결과, 한반도는 홍고추가 84.7%, 반건조 고추가루가 69.9%, 그리고 화건고추가루가 12.9%로 각각 나타났다. (중략)