• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.22-24
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• 1974

1. Object and importance of the research. The exports of plywood are increasing annually and it has ranked first in the world market because of the high quality product developed and manufactured using modern techniques. However, it is known that the exports of the other wood products, except plywood, is inactive because of their low quality. Accordingly, to increase the exports of various wood products investigations were carried out on kiln drying techniques to improve the quality of the wood. 2. The details and scope of the research Wet wood should be kiln dried before use to prevent various drying defects such as distortion, shrinkage etc, which would develop after processing, and also wet wood is not suitable for cutting, gluing and finishing. Therefore, the kiln drying properties of lumber from such species as Persimmon, Oak, Ramin and Meranti which are used in large quantity for manufacturing exporting wood products have been studied. Also the real state of kiln drying industry in Korea was investigated. 3. Results and proposal for practical use of the research 3. 1 Results of the research 3.1.1 The end checks and the time for drying from intial moisture content of about 40 percent to 5 percent moisture content in ovendry were investigated as Table 1. 3.1.2 The kiln dried results, for 30mm stock, which are presented by using kiln schedule Table 2 are as Table 3. 3.1.3 The kiln schedule for Persimmon which has a normal drying properties is given in Table 4. However, the persimmon which has easy checking properties should be air dried under a relative humidity of above 85% until reaching about 25 percent moisture content. 3.1.4 The kiln schedules for ramin, meranti and oak are given respectively as follows. Ramin kiln schedule ............ Table 5 and Table 6 Meranti kiln schedule ............ Table 7 Oak kiln schedule ............ Table 8 3.2 Proposal for practical use of the research Firms using the above species should be informed the results of the research so they can be used to preventing drying defects and shortening drying time.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.303-309
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• 2010

This study was planned to monitor the change in the content of sulfur dioxide during the drying process of fresh vegetables. The analysis of sulfur dioxide was conducted by the Optimized Monier-Williams Method based on the Korea Food Code. The samples were kinds of vegetables which consisted of naturally-originated sulfur compounds (green onion, onion, cabbage, garlic, radish leaves, radish). Fresh vegetables (n = 182) and dried vegetables (n = 41) purchased from different local areas were investigated for the content of sulfur dioxide. The fresh vegetables were dried at 50~$60^{\circ}C$ using hot-air dryer. The moisture contents of dried samples were adjusted to keep 10 percents. The contents of sulfur dioxide in self-dried vegetables were 104.6 mg/kg in green onion, 75.4 mg/kg in onion, 129.1 mg/kg in cabbage, 197.6 mg/kg in garlic, 23.0 mg/kg in radish leaves and 52.5 mg/kg in radish, respectively. The increase of sulfur dioxide content according to the moisture content reduction was different from the expected. It means that the contents of sulfur dioxide can be altered by other factors except moisture contents. This results can be utilized as materials for the safe management of sulfites of dried vegetables.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.330-338
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• 2002

This study was performed to develop natural spices and functional foods using Cheongung (Cnidium officinale) which is one of the Korean medicinal plants. The volatile flavor patterns of Cnidium officinale were detected by electronic nose with 6 metal oxide sensors, and the principal component analysis was carried out. The volatile flavor components of Cnidium officinale were isolated by simultaneous steam-distillation extraction with pentane and diethylether (1 : 1), and essential oils were analyzed by capillary GC and GC/MS. The free radical scavenging activity of ethanol and methanol extracts from Cnidium officinale was measured by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with ${\alpha}-tocopherol$ as reference. The principal component analysis showed the difference of principal components between fresh and drying samples. Eighty-five volatile flavor components (643.64 ppm) from fresh Cnidium officinale were identified and the major components were butyl phthalide, sabinene, neocnidilide. Sixty-four volatile flavor components (218.15 ppm) from hot air dried one were identified and the major components were butyl phthalide, sabinene, 3-N-butyl phthalide. And 73 volatile flavor components (784.15 ppm) from freeze dried one were identified and the major components were butyl phthalide, sabinene, ${\beta}-selinene$. The free radical scavenging activity of methanol cold extract (500 ppm) of freeze dried Cnidium officinale was higher than other samples. And methanol and ethanol cold extracts (above 250 ppm) of freeze dried sample were higher than ${\alpha}-tocopherol$ $25\;{\mu}M$ (22.34%).

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.32-32
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• 2018

이 지침은 조선소의 선박 선박 및 해양플랜트 건조공정 중에 선내 의장 및 도장공사가 이루어지는 안벽공사 등과 같이 실내 위험 작업환경에서 근무하는 작업자의 안전을 확보하기 위해 실시간 작업자의 추적 및 확인 가능한 위치인식 기술에 대한 가이드라인(guideline)을 제시한다. 이 지침은 조선소의 안벽공사 등과 같이 실내 위험 작업환경에서 근무하는 작업자들이 안전하게 작업하기에 매우 열악한 환경을 가지고 있고 작업자들이 선박 내에 어디에 위치하는지, 위험상황에 노출되었는지 등에 대해서 전혀 정보를 알지 못해 작업자들이 작업 중 사고(화재, 공간차단 등)에 직면하였을 경우에도 바로 조치할 수 없는 상황을 해소하기 위해 개발되었다.

• Journal of Biosystems Engineering
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• v.13 no.4
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• pp.38-45
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• 1988

The freeze drying of garlic juice was carried out in a vacuum freeze dryer, laboratory size, by backface heating. The factors which influence the rate of freeze drying, the pressure of drying chamber, the plate temperature, the concentration and the thickness of a sample, were discussed in this study. The drying rate was in proportion to the drying chamber pressure and when the pressure was at 1.5 torr, the foaming occured on the surface of materials, so this condition was not suitable for freeze drying. As the temperature of plate increased, drying rate increased, but when the temperature was $20^{\circ}C$, it was impossible to accomplish freeze drying because the foaming and the dispersion occured in a sample. The higher the concentration of a sample was, the lower drying rate was.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1680-1687
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• 2011

This study was performed to determine the effects of pretreatment and drying methods on the quality and physiological activities of garlic powders. Fresh garlic was boiled, baked, steamed or left untreated before hot-air drying or freeze-drying. Electron-donating abilities were higher in the untreated group for each drying method. Relative EDA of baked group was 32.8%, whereas those of the boiling and steaming groups were 12.4% and 20.1%, respectively. Nitrite-scavenging effects were slightly affected by processing methods. Polyphenol content of the processing group was higher in the hot-air drying than freeze-drying group, and it was significantly highest in the untreated freeze-dried group. The value of polyphenol in the baked group was significantly higher than those of the boiling and steaming groups. Tyrosine contents of garlic powder were higher in the hot-air drying than freeze-drying group, and it was significantly highest in the untreated group of each drying method. Antimicrobial activities of the garlic powders were higher in freeze-drying group compared to the hot-air drying group. Therefore, antimicrobial activities of garlic powder were affected by heating treatments.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.245-250
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• 1998

This research was carried out to investigate the effective methods of browning inhibition on Paeonia lactiflra Pall during hot air dehydratin. After drying for 36 hrs without pretreatment and with briquet fumigation moisture contents of Paeonia lactiflora Pall. was 16.0% and 16.2%, respectively, while with acidic solution, sulfite salt solution and blanching it was lower of 13.5, 12.9 and 14.8%, respectively. Using freeze drying moisture content was highest of 18.8%. The Hunter values of dried Paeonia lactiflora Pall., L, a, band ${\triangle} E$ showed that non-treatment had the most browning with 61.60, 1.89, 10.20 and 39.78, respectively, while briquet fumigation and sulfite salt solution were excellent in reducing browning. During freeze drying browning didn't occur. Paeoniflorin content was 2.41 and 2.51 %, respectively, in briquet fumigation and sulfite salt solution and was the highest (2.70%) in freeze drying. The content of $SO_2$, was 0.63% both in briquet fumigation and sulfite salts. It was 0.15% and 0.17% higher than nontreatment and freeze drying. The most effective pretreatment to inhibit browning of Paeonia lactiflora Pall. was soaking in sulfite salt solution $(0.5% NaHSO_4-0.5% Na_2S_2O_3)$ considering many things such as manpower, economical efficiency, drying time, commodity, etc. but safety should be evaluated to treat sulfite salts solution on peony roots.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.743-748
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• 2013

The purposes of this study are to prepare Hanji fiber-filter sheets using replacement liquid in water-swollen fiber with non-polar solvent such as ethanol, methanol and pentane. The experiments were studied on the selection of optimal non-polar solvent and the optimal drying method for wetted fiber and then were to know physicochemical characteristics of prepared Hanji fiber-filter sheet. The Ethanol as liquid changer in water-swollen fiber was excellent solvent and the optimal drying method for them was freeze drying served with vacuum pump. The bulk density and porosity of prepared fiber sheet from freeze dryer were 0.11-0.13 g/mL, half of natural dried fiber sheet, and 90%, respectively. The results of SEM observation for the fiber sheet prepared with natural drying or heating drying were shown very close structure of fiber wall in dry state. However, the freeze drying sheet were shown the open structure. So, the head loss of freeze drying sheet was very lower than natural drying and heating drying sheets. From the results of BTEX removal experiments, the sheets dried at water wetted condition was shown more higher efficiency than the fiber sheets dried at solvent wetted condition.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.261-266
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• 1984

Soymilk residue was washed separately with acetone, ethanol, isopropyl alcohol and n-hexane, and then dried at $45^{\circ}C$. The dried residues were evaluated for drying rate, color and chemical and functional properties. Washing with acetone resulted in the shortest drying time (1hr) and the highest in protein content (48.8%) and in Hunter 'L' value. The dried residues after treatment with acetone and alcohols showed relatively high values of 4.3-4.7g/g and 8.5-8.7g/g in oil and water absorption, respectively. Addition of the acetone treated residue to wheat flour at a level of 10% affected little in Amylograph viscosity while those treated with other solvents caused a significant decrease in the viscosity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.614-619
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• 1997

To examine effects of drying methods on the formation of N-nitrosamine(NA) in squid during its drying. Three different types of dried products, which were made by sun, hot-air and traditional drying of squid after removal of intestines, were utilized. NA was analyzed by a gas chromatography-thermal energy analyzer. The contents of nitrate and nitrite nitrogen in dried products were in the range of 0 to 5.2mg/kg and 0 to 2.7mg/kg, respectively. The contents of TMAO and betain nitrogen in squid during its drying decreased, while those of TMA and DMA nitrogen increased. The contents in dried products were 27.8~29.2mg% and 10.4~12.3mg/kg, respectively. N-Nitrosodimethylamine (NDMA) was only detected in squid during its drying, recovery from raw sample and its dried pro- ducts spiked with 10$\mu\textrm{g}$/kg for NDPA was 81.0~ 100.0%. NDMA in raw samples was found to be below 0.05$\mu\textrm{g}$/kg. The levels of NDMA in squid increased remarkably during its drying and those in dried products were ranged from 2.7 to 42.7$\mu\textrm{g}$/kg. The effects of drying methods in squid were found to be quite different. the levels of NDMA in traditionally dried products were 11~16 and 3~4 times higher than those in sun dried and hot-air dried products, respectively It is believed that high levels of NDMA were detected in traditionally dried products because NDMA was formed from reaction between various amines and nitrogen oxide produced by combustion of briquet during drying of squid.