• 한국식품위생안전성학회지
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• 제18권4호
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• pp.243-250
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• 2003

S-methylmethionine, vitamin U levels were affected by cultivars, parts fo Korean Chinese cabbages, and drying methods. Among drying conditions, freeze drying method appeared the best condition to maintain bitamin U content compared to oven and air drying methods. In the case of KOrean Chinese cabbages, outward leaves have high levels of chlorphyll and fiber. From this study, the outward parts contained high levels of vitamin U in two cultivars. Leaf parts were 1.1-21.2 times higher in vitamin U levels than midribs in both cultivars. This difference was shown most distinctively in freeze dried outward parts of Winter Pride cultivar. Like vitmnin U, fee amino acids also showed much higher levels in leaves. Levels of amino acids showed irregulatoy changing patterns at different parts and cultivar of Korean Chinese cabbages with various drying methods, Alanine and threonie appeared relatively aboundant amino acids in most parts of samples. Since no distinctive trends were observed in this rsult, it seems no relationship exists between amon oacids and bitamin U levels. Levels of methionine in differnent parts and cultivars of Korean Chinese cabbages dried with various methods did no show clear relationship with tlevel of vitamin U. Moreover, emthionine was not detected in freeze dired outward leaf parts which were the hithest parts of vitamin U levels in Winter Pride and 55 days cultivar. There were simila levels of methionine between overn and freeze drying. Samples prepared by air drying showed significatly lower levels than those by oven and freeze dryting. Methionine as aprecursor of vitamin U, may play a role in an increase of vitamin U during drying of KOrean Chinese cabbages.

• Restorative Dentistry and Endodontics
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• 제49권2호
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• pp.20.1-20.13
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• 2024

Objectives: This study investigated the nanoleakage of root canal obturations using calcium silicate-based sealer according to different drying methods. Materials and Methods: Fifty-two extracted mandibular premolars with a single root canal and straight root were selected for this study. After canal preparation with a nickel-titanium rotary file system, the specimens were randomly divided into 4 groups according to canal drying methods (1: complete drying, 2: blot drying/distilled water, 3: blot drying/NaOCl, 4: aspiration only). The root canals were obturated using a single-cone filling technique with a calcium silicate-based sealer. Nanoleakage was evaluated using a nanoflow device after 24 hours, 1 week, and 1 month. Data were collected twice per second at the nanoscale and measured in nanoliters per second. Data were statistically analyzed using the Kruskal-Wallis and Mann-Whitney U-tests (p < 0.05). Results: The mean flow rate measured after 24 hours showed the highest value among the time periods in all groups. However, the difference in the flow rate between 1 week and 1 month was not significant. The mean flow rate of the complete drying group was the highest at all time points. After 1 month, the mean flow rate in the blot drying group and the aspiration group was not significantly different. Conclusions: Within the limitations of this study, the canal drying method had a significant effect on leakage and sealing ability in root canal obturations using a calcium silicate-based sealer. Thus, a proper drying procedure is critical in endodontic treatment.

• 한국식품영양학회지
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• 제22권2호
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• pp.192-198
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• 2009

Cheongkukjang is a traditional fermented soybean food in Korea that is used in the manufacture of functional foods. This study was conducted to assess vitamin contents and sensory qualities of powdered Cheongkukjang dried by oven drying, far-infrared drying and freeze drying. Vitamins $B_1$, $B_2$, $B_6$, E, niacin and pantothenic acid were detected using all drying methods. However, vitamin D was not detected in the oven drying samples, and was most prevalent($82.47{\mu}g$/100 g) in the far-infrared drying samples. The sensory characteristics included color, off flavor, salty taste, bitter taste, sweet taste, roasted taste and after-taste. Oven drying and freeze drying samples exhibited highest and lowest color scores(5.62 and 2.0, respectively). Oven drying samples also exhibited the highest roasted taste score(4.76), although not significantly different from far-infrared drying samples(4.0, p<0.05), while the score of freeze drying samples(2.38) was significantly different from the other methods(p<0.05). It is concluded that freeze drying is most suitable.

• 농업과학연구
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• 제45권4호
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• pp.847-857
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• 2018

Recently, customers' demand and attention to dried agricultural products or foods have increased due to their convenience and nutritional values. Conventional drying methods such as solar drying and hot air drying have been most widely used for producing a large amount of dried agricultural products; however, those methods require quite a long time and high energy consumption. To compensate for these issues associated with conventional methods, dielectric heating such as microwave and radio frequency heating has been used as a supplemental method in the drying procedure. This study investigated the microwave drying characteristics of squash slices with different thicknesses under different microwave power intensities and determined the best drying model that could precisely describe the experimental drying curves of the squash slices. The squash was cut into slices with two different thicknesses (5 and 10 mm), and then, they were dried under different microwave power intensity ranges between 90 and 900 W with an increase interval of 90 W. Six drying models were tested to evaluate the fit to the experimental drying data, and the effective moisture diffusivity ($D_{eff}$) values of the squash slices under microwave drying were determined. The results clearly show that as the microwave power was increased, the drying time of both squash slices was significantly decreased, and the slope of the drying rate increased. The effective moisture diffusivity was also significantly related with the microwave power intensities and thicknesses of the slices. In addition, the Page model was most suitable to delineate the drying curves of both squash slices under different microwave power intensities.

• 한국식생활문화학회지
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• 제35권1호
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• pp.28-54
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• 2020

This study aims to investigate the food preservation methods adopted by the Joseon Dynasty, which existed before the 17^th century. A total of 232 food preservation methods were discovered in 25 books, and could be classified by their targeted food types: vegetables (84), sea foods (60), meats (41), fruits (37), and others (10). Depending on the preservation method applied, they are classified as food drying, soaking, mud cellar preservation, and other preservation. Food drying is further classified into 8 sub-types: drying, sun-drying, shadow-drying, wind-drying, dry heat, combined drying, smoking, and others. Soaking could be sub-divided into using salt, ash, dry sand, bran, fermented paste, wet distillers grains, oil, and others. Mud cellar preservation is sub-classified into installing shelf inside the mud cellar, making the mud cellar for food preservation, and making hole or underground tunnel for food preservation. Other food preservation methods include minimizing moisture loss by applying beeswax on a section of the vegetable stem, and cutting the vegetables or fruits with their branches and leaves for food preservation.

• Journal of the Korean Wood Science and Technology
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• 제22권4호
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• pp.37-42
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• 1994

The adsorption of water vapor and equilibrium moisture content(EMC) of the specimens for four softwood species dried by conventional- and high temperature method and equilibrated to 15% of the target EMC condition at 25$^{\circ}C$ were determined by oven drying method and with moisture meters. The amount of adsorption for high temperature dried red pine was significantly higher than that of conventional kiln dried wood, while those of eastern white pine, eastern hemlock and Norway spruce were not significantly different between drying methods. EMCs of these four species determined by oven drying method and with capacitive admittance moisture meter were not significantly different between drying methods. EMC of high temperature dried red pine determined with resistance moisture meter was significantly higher than that of conventional kiln dried wood. But EMCs of other species did not show significant difference between drying methods. EMCs of conventional and high-temperature dried wood determined with electronic moisture meters, especially in the case of the capacitive-admittance moisture meter measurement, were lower than that determined by oven drying method.

• Journal of the Korean Wood Science and Technology
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• 제36권5호
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• pp.49-55
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• 2008

This study was carried to investigate the effects of steaming and four different drying methods on the longitudinal liquid permeability of Korean pine (Pinus koraiensis Sieb.et Zucc.) board. Four drying methods were air drying, conventional kiln drying, microwave-vacuum drying and high temperature drying. Darcy equation was used for calculating the specific permeability of the small sapwood specimens taken from the treated boards while capillary rising method was used for the heartwood specimens. The sapwood specimens were extracted with water and benzene-alcohol solution to examine the mechanism of liquid flow in treated wood. No significant correlation was found between specific permeability and the number of resin canals of the sapwood specimens. Extraction decreased the differences of specific permeabilities of the sapwood specimens between the five treatment methods. The effects of extraction on the longitudinal permeability are different between five treatments. The fluid path in heartwood was observed by dynamic observation method.

• 한국약용작물학회지
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• 제14권1호
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• pp.8-13
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• 2006

삼백초의 유효성분과 선도유지에 적합한 건조방법을 구명하고자 건조방법을 달리하여 건조시킨 후 건조방법별 유효성분 함량과 선도를 조사한 결과를 요약하면 다음과 같다. 1. 건조방법별 건조시간은 양건에 비해 열풍건조와 동결건조시 $88{\sim}93%$ 단축되었다. 건물수율은 동결건조 > 양건 > 열풍건조 순으로 높았고, 건조후 수분 함량은 양건 > 열풍건조 > 동결건조 순으로 높았다. 2. 총페놀성 화합물과 quercetin 관련물질 함량은 동결건조 > 열풍건조 > 양건 순으로 높았으며, 열풍건조후 볶음 또는 건조전 증자 처리를 함으로써 감소되었다. 항산화 활성은 동결건조에서 가장 높았고, 열풍건조와 양건 간에는 차이가 없었으며, 열풍건조후 볶음 또는 건조전 증자 처리를 함으로써 증가하여 총페놀성 화합물과 quercetin 관련물질 함량과는 다른 경향을 보였다. 3. 적색도 (a)는 동결건조 < 열풍건조 < 양건 순으로 낮았다. 4. 열풍건조시 부위별 총페놀성화합물과 quercetin 관련물질 함량은 꽃 > 잎 > 세절 > 줄기 순으로 높았으며, 항산화 활성도 유사한 결과를 나타내었다. 부위별 적색도는 잎 < 세절 < 꽃 < 줄기 순으로 낮았다. 5. 삼백초의 유효성분과 선도유지에 적합한 건조방법은 세절하여 동결건조하거나 잎과 꽃만을 열풍건조하는 것이 효과적이었다.

• 한국초지조사료학회지
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• 제33권4호
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• pp.234-239
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• 2013

This study investigated the effects of drying methods and drying time on the changes in anthocyanin content in colored barley. Colored barley cultivar Boanchalbori was harvested at a time when the anthocyanin content was the most and dried in afield. The harvested barley was then treated by two methods, sun drying and shade drying, for 4, 8, 24, and 32 h. The moisture content of the sun-dried barley decreased slightly faster than shade-dried samples, but the difference was not statistically significant. Chemical analysis indicated that the samples dried under shaded conditions had slightly higher crude fiber and lower nitrogen free extract, but the difference was not statistically significant. There was no difference in the total digestible nutrients between the two methods. In the case of sun-dried barley, the anthocyanin content decreased compared to the control and shade-dried samples after drying for 4 h (p < 0.05), was maintained at a constant level at 24 h, and then decreased at 32 h. In case of shade-dried barley, the anthocyanin content decreased gradually with the drying time, and a significant decrease was found at 24 h of drying (p<0.05) as compared to the control. The shade-dried method was more successful in reducing anthocyanin loss than the sun-dried method (p<0.05). There was a slight decrease in 1,1-Diphenyl-2-Picrylhydrazyl radical scavenging with drying time in the shade-dried method, and a significant decrease after 4 h with the sun-dried method. These results showed that covering with a two-layer awning was advantageous to dry colored barley in the field conditions.

• 한국작물학회지
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• 제47권6호
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• pp.459-464
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• 2002

작약근이 수확되어 적절한 조제과정을 거쳐 약품으로서의 생약재 작약이 가공되는 과정 중 약성을 가장 크게 변화시키는 수치 및 건조방법의 차이가 작약근 함유 생리활성 성분의 함량변화에 미치는 영향을 조사하기 위하여 4년생 의성작약의 뿌리를 이용하여 코르크층을 제거한 거피근과 코르크층을 제거하지 않은 유피근으로 가공하고, 유피근, 거피근 모두 상온 음건, $50^{\circ}C$ 화력건조, 수증건법 및 동결건조 방법으로 건조한 후 이들에 함유된 작약근 생리활성 성분의 함량을 검토한 결과를 요약하면 다음과 같다. 1. 건조방법의 차이에 따른 paeoniflorin, albiflorin 및 (+)-taxifolin 3-O-$\beta$-D-glucopyranos의 함량은 상온 음건 조건의 건조법에서 가장 높은 양상을 나타내었고, 동결건조가 가장 낮은 함량을 나타내었다. 2. 건조방법에 따른 유피근과 거피근간의 paeoniflorin, albiflorin, (+)-taxifolin 3-O-$\beta$-D-glucopyranoside의 함량을 비교할 때 상온 음건을 제외한 모든 건조법에서 거피근의 함량이 더 높은 양상을 나타내었다. 3. gallic acid의 함량은 유.거피근 모두 $80^{\circ}C$ 수증건법이 가장 높은 함량을 나타내었고, 동결건조법이 가장 낮은 양상을 나타내었다. 4. benzoic acid의 함량은 gallic acid와 상반된 양상을 나타내어 동결건조법이 유.거피근 모두 가장 높았고, $80^{\circ}C$ 수증건법이 가장 낮은 양상을 나타내었다. 5. 건조방법에 따른 (+)-catechin 및 (-)-epicatech고 함량은 동결건조법이 다른 건조법보다 높은 양상을 나타내었다. 6. paeoniflorin, albiflorin, (+)-taxifolin 3-O--$\beta$-D-glucopyranoside, (+)-catechin 및 benzoic acid의 함량은 건조 및 처리 온도가 증가할 수록 감소하는 양상을 나타내었다.