• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.29-37
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• 2008

The objective of this research is to evaluate the optimum treatment methods for disposal sludge cake at different temperatures and periods of time. The disposal dehydrated sewage cake used in this study was obtained from N wastewater treatment plant in the P City. This system consists of continuous conveyer thermal dryer and pyrolysis. The continual conveyer thermal dryer was operated to evaluate the optimum conditions with temperature settings, ranges from 130 to $180^{\circ}C$, loading rates of 650~750 kg/hr and operating times of 110~120 minutes. The continual pyrolysis was also operated to evaluate the optimum conditions with temperature settings, ranges from 650 to $750^{\circ}C$, loading rates of 100~158 kg/hr and operating times of 20~40 minutes. The sewage sludge cake has a moisture content of 78~80% (wt) which decreased up to 1~3%(wt) resulted in breaking of cell wall after operating the continuous conveyer thermal dryer and pyrolysis. Important parameters which were operating times, moisture contents, loading rates, conveyer velocities and rotary velocities effects on the thermal kinetics and dynamics were investigated to evaluate the optimum conditions for the continual thermal dryer and pyrolysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.6023-6028
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• 2013

Recently, biodegradable polymers are gaining more and more attention due to international environmental issues. Succinic acid is synthesised by chemical process of hydrogenation. Succinic acid synthesized has certain amount water content. To remove the water contained in succinic acid is used generally by hot air drying process. But recently, microwave drying process having the advantage of shortening the drying time and uniform drying of product are gaining more attention. In this study, hot air drying and microwave drying efficiency were compared at drying process. In addition, we confirmed commercial applicability in microwave drying process of succinic acid. Microwave drying process has higher efficiency than 70% compared with hot air drying process at thickness of 1cm. Economic efficiency were compared through examination of power consumption for complete drying of succinic acid at microwave and hot air dyring.

• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.185-189
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• 2012

This study was conducted to investigate the effect of different steam condition and dehydration condition on physicochemical characteristics of Olbyeossal made from Waxy rice. All samples were steamed at $95-100^{\circ}C$ for 60 min or at $121^{\circ}C$ for 20 min and then were dehydrated using hot air 45, 60, $80^{\circ}C$ and sun-dried to achieve moisture contents 13-15%. Initial pasting temperature of Olbyeossal was the lower than that of nontreatment sample by parboiling. The combination in steaming $95-100^{\circ}C$ and hot drying at $45-60^{\circ}C$ was showed appropriate pasting properties compared with other condition. The hardness of Olbyeossal was significantly affected by steaming and dehydration condition. The hardness of Olbyeossal showed the higher value for steaming at $121^{\circ}C$ than $95-100^{\circ}C$. The water binding capacity (WBC) and swelling power (SP) were higher steaming at $121^{\circ}C$ than $95-100^{\circ}C$. No significant differences on WBC and SP of Olbyeossal by dehydration condition were observed. As the sensory evaluation results, the combination in steaming at $121^{\circ}C$ and hot-air drying at 45 or $80^{\circ}C$ led to increase preference for appearance, color, taste and overall acceptability. These results indicate that steaming and dehydration condition were affecting factor on physicochemical characteristics of Olbyeossal.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.447-451
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• 2019

6-gingerol can be converted to 6-shogaol, one of the predominant active compounds found in ginger, via processing such as drying and extraction. Subcritical water extraction is the environmentally friendly method of extraction of bioactive compounds using only purified water as a solvent. This study investigated subcritical water extraction ($190^{\circ}C$, 15 min) of 6-gingerol, and 6-shogaol from dried ginger (Zingiber officinale) including drying conditions such as temperature (room temperature, 60, $80^{\circ}C$, and freeze drying) and time duration for drying (1-4 h). The amount of 6-gingerol was found to be reduced, and that of 6-shogaol was found to be increased depending upon the water content of dried ginger. Upon oven-drying ginger at $60^{\circ}C$ for 2 h, the maximum yields of 6-gingerol ($0.18{\pm}0.02mg/g$ fresh weight), and 6-shogaol ($0.47{\pm}0.02mg/g$ fresh weight) were obtained upon subcritical water extraction.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.214.1-214
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• 2003

본 연구는 4~6개월의 유아들을 위하여 재수화시킨 후 숟가락으로 떠먹일 수 있도록 쌀을 기본으로 하고 당근, 쇠고기 및 계란을 각각 주재료로 한 냉동건조 이유식 제조의 최적조건을 결정하기 위하여 수행되었다. 본 연구에서 얻어진 결과를 요약하면 다음과 같다. 당근, 쇠고기 및 계란이유식에서 모두 냉동건조시간은 수분함량이 높고 가열판 온도가 낮을수록 증가하였다. 파쇄성은 수분함량이 감소하고 가열판온도가 증가함에 따라 증가하였다. 관능적 특성 중 수화속도, 균질성 및 매끄러운 정도는 수분함량이 증가하고 가열판 온도가 감소할수록 증가였고, 뜨기 쉬운 정도는 수분함량이 증가할수록 증가하였으나, 가열판온도의 영향은 거의 받지 않았다. 또한 피막형성성은 수분함량과 가열판온도가 증가할수록 증가하였다. 이유식 제조치 최적조건은 당근이유식의 경우 수분함량 88.5%와 가열한 온도 34$^{\circ}C$로, 쇠고기이유식에서는 수된함량 88.5% 와 가열판온도 28$^{\circ}C$로, 그리고 계란이유식에서는 수분함량 87.5%와 가열판 온도 39$^{\circ}C$로 결정되었다.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.667-674
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• 2013

This study was aimed to investigate the effect of microwave-assisted extraction on Schizandra fruit extract dried by two different treatments: freeze-drying and hot air-drying. Two extraction parameters were measured in particular: total polyphenol content and antioxidant activity. Both values were found to increase as the microwave power increased, for both drying processes. However, the extract from the freeze-dried sample exhibited higher antioxidant activity than that from the hot air-dried samples. Additionally, the total polyphenol content and antioxidant activity of the extract from the freeze-dried samples increased with the extraction time, whereas they decreased with the extraction time in the case of the hot air-dried sample. Solvent concentration was also found to have a significant effect on total polyphenol content and antioxidant activity; the highest values for both properties were achieved at 50 and 70% ethanol concentrations, respectively. In summary, a higher total polyphenol content and antioxidant activity were observed for Schizandra fruit extracted by freeze-drying than that by hot air-drying.

• Food Science and Preservation
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• v.18 no.4
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• pp.488-496
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• 2011

Cold-air drying was conducted for a steamed pumpkin-sweet potato slab to improve its quality, convenience, and preference as a snack. A steamed pumpkin-sweet potato slab was dried from 10 to $25^{\circ}C$ for 48 h, and its moisture content, color, texture, and taste at different drying temperatures and drying times were evaluated. The lowest moisture content was 4.98%, at $25^{\circ}C$. The lightness decreased, but the other color values (a, b, and ${\Delta}E$) increased with the increasing drying temperature and drying time. The reducing sugar and soluble solid ranged from 98.7 to 194.75 mg/g and 19-70 $^{\circ}Brix$, respectively. The highest hardness of the steamed pumpkin-sweet potato slab was 23.88 $kg_f/cm^2$, and the springiness and cohesiveness were 91.15 and 98.36% when it was dried at $25^{\circ}C$ for 48 h. The sensory evaluation score was high at $10^{\circ}C$, 40 h and at $25^{\circ}C$, 24 h. The optimum drying condition was predicted at $19^{\circ}C$, 32 h via response surface methodology (RSM).

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.301-306
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• 1999

현재까지 인삼건조에 관한 연구는 단편적이며 또한 열풍건조의 온도 조건에 따른 물리 화학적 품질 변화 등에 국한되고 있으며 최 등(1992)이 백삼과 태극삼의 평형함수율과 열풍 건조 방정식을 체계적으로 개발한 연구가 있었으나 건조 에너지와 품질의 관점에서 새로운 건조기의 개발 등에 관한 연구는 거의 없는 실정이다. (중략)

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.206-211
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• 2004

It is very important to minimize the acid value of oil in the oil and fat industry, because acid value of oil products are a indicator quality. This study was performed to investigate change of moisture content, acid value and free fatty acid content by drying condition such as drying method, temperature and drying time on steamed duck egg york. Also, change of fatty acid composition by acid value. The acid values, moisture contents and free fatty acid contents were showed comparatively lower value by spray drying and freeze drying than by steam drying. but difference that keep in mind between each drying method was not looked. Whereas moisture content, acid value and free fatty acid content of effect of drying temperature reaches in lowest value. also, did not show change until dry 12hours reaching to lowest value by 3.1, 3.0％ and 0.98％ after dry 9hours both moisture content, acid value and free fatty acid content. Also, acid value increase, free fatty acid was increased, where unsaturated fatty acid showed that decrease rapidly.

• Journal of Conservation Science
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• v.16 s.16
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• pp.110-118
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• 2004

In order to evaluate two-step treatment of PEG-freeze drying for highly-degraded waterlogged ash woods (Fraxinus PP.; ca. 5,700 BP), which were excavated from peat lands in western Korea, dimension stability was examined during 45 months after complete treatment. The samples pre-treated with PEG in water solution showed better dimensional stabilities than the ones with PEG in t-butanol(TBA) solution. It suggests that TBA reduced the flexibility of wood cells and overflying by TBA induced micro-checks during freeze drying. Micro-checks results in fragile wood structures and consequently, large shrinkage by moisture absorbances of high PEG contents during exposure in humid condition. The results suggest that PEG in water-solution treatment is better than PEG in t-butanol as pretreament for freeze drying of highly-degraded waterlogged ash woods.