• Culinary science and hospitality research
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• v.22 no.2
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• pp.104-114
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• 2016

In this study, the quality characteristics of different drying methods of Cirsium setidens Nakai, which contains large amounts of biological substances, were investigated for the improvement of their practical use. During the drying period, the weight reduction was the highest with hot-air drying(82.7%). As for the general component and mineral contents analysis results of Cirsium setidens Nakai, there were no significant difference. Cyclic low pressure drying resulted highest amount of total phenolic components and 1,1-diphenyl-2-picrylhydrazyl (DPPH). Hence, cyclic low pressure drying method is the best method for enhancing antioxidant activity of Cirsium setidens Nakai.

• Food Science and Preservation
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• v.5 no.4
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• pp.346-349
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• 1998

This study was investigated to changes of texture, color and chemical properties in jujube fruits which dried by sun and hot air instrument. Weight and moisture contents were the lowest in jujube fruits dried by sun thin those of others. The ratio of water uptake was the highest in jujube fruits dried by hot air drying than those of others. The hardness and rate of rotting of dried jujube fruits were the highest in sun (Dying than those of others. The browning of jujube fruits dried by sun was higher than that of jujube fruits dried by other methods. Ash content was the highest in sun dried fruits than those of others, and content of vitamin C was the lowest in nm dried fruits than those of others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1573-1579
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• 2004

This study was conducted to develop intermediate material for new processed food from sweet pumpkin. Osmotic dehydration was carried out as pretreatment before drying. After the sweet pumpkins were pretreated under optimized osmotic dehydration conditions, they were dried by three drying methods (hot air drying, vacuum drying and cold air drying). The moisture contents of dried sweet pumpkin products by osmosis treatment (sucrose) and hot air drying, vacuum drying, and cold air drying were 14.48, 14.09 and 13.87%, respectively. Cold air drying preserved more vitamin C content and showed lower color difference than hot air drying and vacuum drying. As a result of microscopic analysis, cold air dried sweet pumpkin was observed regular tissue, while hot air and vacuum dried sweet pumpkins were observed a cell collapse following the loss of water.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.877-882
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• 1998

To establish optimum drying methods for Korean yam, freeze drying, cool air drying and hot air drying methods were compared by determining some quality criteria. The native color, odor, taste and viscosity of raw yam were preserved by only freeze drying at less than $40^{\circ}C$. The native white color of yam changed to brown and odor and taste of yam decreased largely by cool air drying and hot air drying. Especially cooked and roasted flavor was developed in hot air dried yam. The viscosity of cool and hot air dried yam was about half than that of freeze dried yam. Conclusively freeze drying method was shown optimum to preserve quality properties of yam such as viscosity, color, odor and taste. The physical properties of yam powder such as dispersiveness and solubility was the best in $40{\sim}60{\;}mesh$ particle size.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.303-308
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• 2014

This study determined the antioxidant levels and activities of hot water aronia extracts by different drying methods such as sun drying, sun drying after steam treatment, freeze-drying, and oven drying. The total polyphenol content, calculated as gallic acid equivalent, was the highest in the freeze-dried sample (910 mg), followed by sun-dried after steam treatment (779 mg), sun-dried (769 mg), and oven-dried (757 mg) samples. Similar patterns were observed for the total flavonoid and anthocyanin contents. Freeze-dried aronia samples contained the highest polyphenol, flavonoid, and anthocyanin contents as compared to the samples dried by other methods. All antioxidant activities were found to increase in a dose-dependent manner. For the hot water-extracted freeze-dried aronia powder (200 mg/mL), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radicalscavenging activities were 65.5% and 61.7% and the hydroxyl and superoxide anion radical-scavenging activities were 50.5% and 52.1%, respectively. These results suggest that comparatively, freeze-drying is a better method for preserving the bioactive components and the antioxidant activities of aronia.

• 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.179.1-179
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• 2003

본 연구는 각종 영양성분과 기능성 물질을 함유한 식용마의 소비확대와 새로운 가공식품을 개발하고자, 당절임한 식용 마의 건조방법에 따른 물성 및 일반 성분의 변화를 조사하였다. 동결건조한 당절임 식용마의 명도는 높았고 적색도와 황색도는 열풍 및 진공 건조한 것에 비해 낮았으며, 수분함량과 재수화율은 동결건조한 것이 높게 나타났다. 수용성 단백질은 동결건조한 것이 6.43mg/100g으로 가장 낮았으며 총당과 환원당의 함량은 건조방법에 따라 뚜렷한 차이가 없었다. 주요 유기산은 malic, acetie, citric acid 이었고, acetic, citirc acid는 열풍 및 진공 건조한 것이 많았으나 malic acid는 동결 건조한 것이 월등히 높게 나타났다. 구성아미노산은 진공 건조한 것에 많았으며, 유리아미노산은 큰 차이가 없었다. 총 비타민 C함량도 별다른 차이가 없었으나 환원형 비타민 C는 동결이 산화형 비타민 C는 열풍 및 진공 건조한 것이 높게 나타났고, 무기질 함량은 K, Na, Mg의 함량이 많았다. 마 스낵의 관능검사에서는 열풍 및 진공건조에 비해 동결 건조한 것이 우수한 것으로 평가되었으며, 전자현미경적 관찰에서는 열풍 및 진공 건조한 것은 세포와 세포벽의 형태를 찾아 볼 수 없었으나 동결 건조 한것은 세포의 형태와 세포벽의 파괴가 일어나지 않았다. 본 연구는 당절임한 식용 마의 건조 방법에 따른 물성 및 성분의 변화를 조사한 결과, 동결건조한 것이 품질이 우수하였고, 영양성과 기능성을 함유한 마의 가공 식품의 개발의 가능성을 제시한다.

• Journal of the Korean Wood Science and Technology
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• v.18 no.4
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• pp.3-8
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• 1990

근년에 전세계에서 목재건조 기술의 주요 관심사는 첫째 건조응력발생과 건조결함 예방이고, 다음은 건조실 제어시스템, 건조스케줄개발, 목재수분이동, 함수율측정, 새로운 건조방법개발, 건조에너지 절약, 경제성분석, 태양열건조, 수학적모델링, 건조전처리, 마이크로웨이브 건조, 건조실 구성과 정비, 건조종기결정, 감압건조, 공정제어와 콘다숀닝, 제습건조, 목재치수 안정 및 고온건조 등의 순위이다. 건조중 발생하는 결함들은 건조경비 증가에 절대적인 영향을 끼칠 수 있다. 예를 들면, 가구공장에 있어서 건조재의 품등 향상에 따른 1%의 수율 증대 효과는 가구 부품 1000 보오드피트당 23$의 생산비를 절감할 수 있고, 활엽수재의 천연건조시 수반되는 건조손상은 생재의 23%를 초과할 수 있다. 본 총설이 각종 문제를 개선하고 건조경비를 절감하는데 기여할 수 있기를 바라며, 또한 단판, 칩 또는 땔감과 같은 비제재품에 관한 건조에 관한것은 제외하였다.

• Food Science and Preservation
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• v.12 no.5
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• pp.417-423
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• 2005

To replace the traditional drying method with improving the qualities of dried squid, warm air drying method was investigated comparing with natural drying method. In respect of drying rate, about 12 hrs were taken to obtain 25% moisture content -which was considered as proper moisture content to control microbial and quality degradation- by warm air drying at 35$^{\circ}C$. However, 120 hrs were taken to obtain such moisture content by natural drying. The squid dried by warm air showed little color difference and was seemed to be raw squid meat color. TBA values were more rapidly increased but final values were lower, inversely. Free amino acid contents were higher, and cholesterol content was lower in warm air drying.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1589-1595
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• 1999

Reverse osmosis(RO) and rotary evaporation, freezer drying and spray drying as concentration and dehydration methods were, respectively, employed to investigate their effect on the flavor quality of ginger powder. Rotary evaporation and spray drying methods were more effective to restrict the browning of ginger powder than RO and freezer drying methods. Concentration methods had no effect on the free amino acids and free sugar contents of ginger powder, but freezer drying resulted in the less quality loss than spray drying. And the powder prepared from enzymatically hydrolyzed extract contained less crude protein, crude ash, browning and the changes in free amino acids, but had more the crude fat, solubility and free sugars than that from ginger extract obtained by filter press. Sensory results indicated that quality of ginger powder prepared by RO concentration and freeze drying of enzymatically hydrolyzed extract was as good as that without enzyme hydrolysis

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.105-112
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• 2016

The drying test was carried on the globular type cow manure pellet for use in solid fuel applications. The globular type cow manure pellet fuel was sorted according to size by rotatory sieves. The three kind of drying methods such as convection hot-air drying method, infrared ray drying method and superheated steam method were used to dry the globular type cow manure pellet. Among the three kind of drying methods, superheated steam method of dry time was the shortest. The apparent specific gravity and low calorific value of dried cow manure pelltes was about $250{\sim}350kg/m^3$ and above 3,000 kcal/kg respectively. The smaller the particle size of cow manure pellets, the less drying time was required. The time was required very less for drying smaller particle size cow manure pellet when compared to larger size. In the case of the same drying condition, it has been found that reducing the particle size of cow manure fuel pellet is an important factor for shortening the drying time of the livestock manure pellet.