• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.245-250
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• 1977

Experiment were conducted to find out the effective drying method of citrus peel produced in Korea by varying the temperature of hot air, surface area of peels, peels from several citrus varieties and physicochemical treatment of the peel. 1. About $3{\sim}6\;days$ were required to reduce the moisture level of the peel from 70%(wet basis) to 20% at room temperature without forced convection. 2. Drying was speeded up until the temperature of hot air reached $60^{\circ}C$. Beyond that no significant increase in drying rate was observed. About 50 minutes were needed to reduce the moisture level (dry basis) to below 10% at $60^{\circ}C$ by forced convection 3. When the peel surface area was increased twice by cutting the peel into 256 fractions, the overall drying time (the time required to reduce the moisture level to 10%, dry basis) was shortened to 15 minutes from 50 mintes of the original peel. 4. No significant difference in drying rate was observed among the peels from several citrus varieties except Shaddock jabon and Citrus ponki tanaka, which dried more slowly than others. 5. Treatment of $Ca(OH)_2$ and the pressing of the peel before drying were effective in drying only when the initial moisture content was substantially higher.

• The Journal of Natural Sciences
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• v.15 no.1
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• pp.97-109
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• 2005

This experiment was established to find out the effect of drying methods on the fruit and powder color of red pepper. Hunter's L, a, and b values of the dried fruit were also higher with the cut fruit in comparison with the whole or punched fruit. The Hunter's a value of the pepper powder after drying and grinding was slightly higher for the whole fruit with sun drying, but it was higher for the cut fruit in case of heat drying. The ASTA value was higher when pepper fruits were sun dried. For the heat drying, the value was higher with the drying temperature $60^{\circ}C$.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.60-66
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• 2009

This study was conducted to investigate into the effective drying method for three greens such as bang-a (Isodon japonicus), aster (Aster yomena) and lettuce greens (Ixeris dentata) Nakai. We have dried three greens using the different drying methods, have made methanol extracts and have also determined the physiological activities in $1,000mg{\cdot}L^{-1}$ extracts. Total phenolic compound contents were most increased by 65.1 and $60.2mg{\cdot}L^{-1}$ in the extracts of bang-a and aster which were frozen dried, however, that in lettuce greens were oven dried by $51.2mg{\cdot}L^{-1}$. Total flavonoid contents were extremely much more in bang-a extracts dried in the oven by $70.6mg{\cdot}L^{-1}$, however, aster and lettuce greens extracts frozen dried by 53.9 and $35.8mg{\cdot}L^{-1}$. DPPH radical scavenging activity in bang-a extracts were greatly increased by 78.8% when bang-a were frozen and dried, however, that in aster were not significant by $89.8{\sim}90.9%$. DPPH radical scavenging activities in lettuce greens extracts were became highest in the order f oven drying (91.9%), natural drying (91.0%) and freeze drying methods (90.9%). Nitrite radical scavenging activities in bang-a and aster extracts were most increased in the natural drying treatment by 73.3 and 78.2%, however, that in lettuce greens extracts were highest in freeze drying treatment by 75.1%.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.2
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• pp.67-74
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• 2001

A field experiment was carried out to determine the effects of chemical/mechanical treatments at mowing on the field drying rate and hay quality of alfalfa(Medicago sativa L., cv. Vernal) and spring oats(Avena satvia L., cv. Swan). The chemical drying agent of 2% $K_2CO_3$, mechanical mower conditioning, and no treatment(control) were treated for hastening hay-making in the spring of 1997. The forages were harvested at early bloom stage in alfalfa and heading stage in oats. After field dry, square bales were made by hay baler, and the dry matter(DM) loss, visual estimation and nutritive value of hay were evaluated after storing two months. The field drying rates of alfalfa and oats were high at mechanical treatment, but the drying effectiveness of chemical agents alone was very low. With mower conditioning, the duration of field dry was shortened by 1 day compared with control. therefore, mower conditioning enhance the field drying rate of alfalfa and oats. The DM loss of alfalfa and oats hay was reduced by mechanical treatment, but the efficiency by chemical alone was low. The visual score(leafiness, green color, odor and softness) of hay at mechanical treatment was slightly higher than that of chemical and control. The nutritive value(ADF, NDF, in vitro digestibility, and relative feed value) of hay was also high with treatment of mechanical, but those of chemical alone were similar compared with control. The nutritive value of hay after two months in both alfalfa and oats was decreased when compared with at harvest.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.173-178
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• 2002

Fresh Shiitake mushrooms were irradiated by UV-B or dried by using hot air to increase the vitamin D$_2$content. Vitamin D$_2$content was determined by high-performance liquid chromatography Irradiating the inside of the mushroom cap was more effective in increasing vitamin D$_2$content than irradiating the outside of the mushroom cap. Irradiation of UV-B at 0, 2.5, 5.0, 7.5 and 10 J/㎠ increased the content of vitamin D$_2$in the mushroom to 21.51, 120.78, 144.38, 168.08, and 187.69 $\mu\textrm{g}$/g, respectively. Vitamin D$_2$content of Shiitake mushrooms with irradiation of 10 J/㎠ decreased from 187.69 to 98.78 $\mu\textrm{g}$/g by 6 hours of hot-air drying. When three kinds of drying method (UV-B irradiation followed by hot-air drying, hot-air drying, and sunlight drying) were compared, the combination of UV-B irradiation and hot-air drying was the most effective in terms of increasine the vitamin D$_2$content in the mushroom.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.380-386
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• 1995

An attempt was made to determine the effects of drying methods including shady air drying, presteamed and shady air drying, microwave drying, and freeze drying on the volatile flavor components with Commelina communis L.. Essential oils from the samples were isolated by simultaneous steam distillation-extraction(SDE) method using diethyl ether as solvent. Concentrated samples were analyzed by gas chromatography(GC) and combined gas chromatography-mass spectrometry(GC-MS). Respective 29, 47, 36, and 24 volatile flavor components were identified in shady air dried samples, presteamed and shady air dried samples, microwave dried samples, and freeze dried samples. The kinds and amounts of volatile flavor components were evidently depended upon the drying methods. 6,10,14-trimethylpentadecanone was regarded as the most abundant component in shady air dried samples, 6,10,14-trimethyl-2-pentadecanone in presteamed and shady air dried samples, neophytadiene in microwave dried samples, and ethyl acetate in freeze dried samples.

• Korean Journal of Medicinal Crop Science
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• v.10 no.1
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• pp.24-28
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• 2002

Effect of pretreatment processing (peeling time, drying temperature, sample type) on the quality of hot air drying peony roots was investigated. Peony roots were peeled for 0, 10, 20, 30, 60, 90 and 120 minute in the peeling machine after water washing. Sample types were whole or cut (thickness of 3mm). Temperatures of hot air drying were 30, 40, 50 and $60^{\circ}C$ The level of water contents in dried sample was $14{\sim}15%$. Drying time was muth reduced as the peeling time, cutting sample types and higher temperature. Contents of paeoniflorin were maintained highest amount (3.48%) in the non-peeling cut sample dried at $30^{\circ}C$ and lowest amount (2.29%) in the 120min-peeling whole one dried at $60^{\circ}C$. Skin color of dried peony roots was heavily discolored in the sample of non-peeling whole type dried at $60^{\circ}C$ and the color was dark brown $({\Delta}E\;was\;46.1)$. When considering shortening of drying time, preservation of active compounds and maintenance of color, the best pretreatment method of drying in peony roots was non-peeling, cut type processing.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.1-8
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• 2016

The purpose of this study is to predict the cracking behavior and suggest the method of controlling the cracking in concrete box culvert for power transmission due to differential drying shrinkage. Drying shrinkage cracking is mainly influenced by the moisture diffusion coefficient that determines moisture diffusion rate inside concrete structures. In addition to the diffusion coefficient, surface coefficient of concrete surface and relative humidity of ambient air simultaneously affect the moisture evaporation from concrete inside to external air outside. Within the framework of drying shrinkage cracking mechanism, it is necessary to perform the numerical analysis, which involves these three influencing factors to predict and control the shrinkage cracking of concrete. In this study, moisture diffusion and stress analysis cor responding to drying shrinkage on concrete box culvert are performed with consideration of diffusion coefficient, surface coefficient, and relative humidity of ambient air. From the numerical results, it is found that cracking behavior due to differential drying shrinkage of box culvert shows the different feature according to three influencing factors and the methodology of controlling of drying shrinkage cracks can be suggested from this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.95-98
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• 1985

This study was carried out to investigate changes in the compositions of fatty acids according to the different drying methods of raw mugwort. Raw mugwort from Kang-wha was dried with four methods such as sun-drying, shady sun-drying, heated oven-drying and freeze-drying. Total contents and fatty acid compositions of the ethyl ether extracts from the dried mugworts were examined. Total contents of the ethyl ether extracts showed remarkable differences with drying methods; freeze-dried mugwort had the highest content (5.60%), while oven dried mugwort revealed the lowest content (2.45%). Eleven fatty acids and four unknown peaks were identified by gas-liquid chromatography; major fatty acids were linoleic acid, linolenic acid and palmitic acid. Fatty acids of mugworts dried by 4 different methods were the same in kinds, but different in their compositions. The content of polyunsaturated fatty acids $(C_{18:2}+C_{18:3})$ was the highest and the loss of low volatile fatty acids was the least in mugwort dried by the freeze-drying method. The volatile fatty acids considerably decreased in oven-dried mugwort. However, the contents of polyunsaturated fatty acids were a little higher in oven-dried mugwort than in sun-dried and shady sun-dried mugwort, and the lowest in sun-dried mugwort.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.4032-4038
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• 2014

Vegetable fatty acid solid soap requires a drying process for moisture evaporation and hardness after being manufactured through saponification. Although the soap is manufactured by mixing additives mainly from natural ingredients, existing studies have focused primarily on the usability of vegetable solid soap. Consequently, research into the physical properties of vegetable fatty acid solid soap mixed with natural ingredients has been unsatisfactory. Therefore, this study attempted to compare and observe the changes in the physical properties (pH, surface tension, critical micelle concentration, and cleansing power) of solid soap in accordance with the drying period and additives (tea tree E.O and $TiO_2$) using pH paper, the Du Nouy measurement method, sedimentation method, and ultrasound washer. Regardless of the mixture with additives, vegetable fatty acid solid soap showed the same pH, and there was no change in the pH while maintaining pH 8 beginning from the $2^{nd}$ weeks to $12^{th}$ weeks of drying. In addition, as a result of measuring the surface tension and CMC, regardless of the drying period, only the soap added with $TiO_2$ showed an even value of 62.5mg/L, whereas the other soap specimens showed a decline in CMC to 25mg/L on the fourth week of drying. As a result of measuring the detergency, the removal efficiency of vegetable fatty acid solid soap mixed with tea tree E.O and $TiO_2$ and dried for four weeks was 4.50~4.65%, which was higher than that of the vegetable fatty acid solid soap without additives (3.62~3.92%).