• 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.

• 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%.

• 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.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.726-735
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• 2016

This study was carried out to evaluate the high-temperature drying characteristics of douglas-fir, hemlock, and radiata pine square timber with dimensions of thickness 15 cm and 18 cm. As a result, radiata pine showed the lowest final moisture content followed by douglas-fir and hemlock without reference to the timber size. Moreover, when the longitudinal kerfing is processed, the final moisture content was lower than control. The kerfing treatment was effective to decreasing the twist of radiata pine and hemlock. When douglas-fir is processed to the shape like the edge-grained timber that does not include the pith, the decrease of drying defect was possible.

• Archives of Pharmacal Research
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• v.29 no.9
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• pp.735-740
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• 2006

Lactic acid bacteria (LAB) quickly attenuate or are killed during the freeze-drying process and storage. The effect of some natural polysaccharides, which are known as potent antitumor and immunomodulating substances, on the viability of the LAB, Lactobacillus acidophilus and Bifidobacterium breve, on freeze-drying and storage were investigated. Among the polysaccharides tested, red ginseng polysaccharide (RGP) and chitosan significantly inhibited the cell death of the LAB during freeze-drying, and fucoidan and RGP most potently protected the cell death of the LAB during storage. The stabilities of the LAB on the addition of RGP and fucoidan were comparable to that of skimmed milk. However, white ginseng polysaccharide (WGP) did not promote storage stability. When 5% skimmed milk/5% RGP treated LAB were freeze-dried and stored, their viabilities were found to be significantly higher those treated with 5% or 10% RGP. The stabilizing effect of 5% RGP/5% skimmed milk during LAB freeze-drying and storage stability was comparable to that of treatment with 10% skimmed milk. Based on these findings, we believe that RGP beneficially improves the stability of LAB during the freeze-dry process and storage.

• Journal of the Korean Wood Science and Technology
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• v.39 no.2
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• pp.125-131
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• 2011

The characteristics of radio-frequency/vacuum drying Japanese larch boxed heart round logs with 150 mm and 210 mm in diameter and 2,500 mm in length, subjected to compressive loading, after the pretreatment of kerf were investigated. The results of this study were as the follows: The drying time of about 120 hours~130 hours was needed from green to about 15 percent of moisture content. The gradient of final moisture content for all specimens was very gentle in both longitudinal and transverse directions owing to dielectric heating. The surface checks seriously occurred although the occurrence extent of surface check for the kerfed specimens was slight compared with that for the control specimens because drying stress was relieved by kerf. The occurrence of surface checks for the L-specimen was more serious than that for the S-specimen.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.249-257
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• 2004

Drying and curing characteristics of PCM resins using the induction heater and short-wave infrared emitter module was studied to develop a compact oven system for the high speed CCL and post-treatment equipment. Drying of the polyester resins using the induction heater and infrared heater showed that the blistering tendency of polyester resin coating increased regardless of additives and colors of resins as the heating rate and/or dry film thickness increased. The blistering of polyester resin coating layer occurred when the heating speed was over than $25^{\circ}C/sec$ for the dry film thickness of $19\~20um$, which is the typical thickness of finish coating in CCL. So did it when the heating speed was over than $40^{\circ}C/sec$ for the dry film thickness over than 10 um. The heating efficiency of paint coated steels by the infrared heating was strongly dependent on the colors of paint coating and generally increased for the dark surface and/or coating. But the faster drying of the PCM resin coatings increased the blistering tendency of coating layer. The blistering limit for the typical finish coating by the infrared heating was estimated as the heating rate slower than $20^{\circ}C/sec$ regardless of colors of PCM resins.

• Journal of the Korean Wood Science and Technology
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• v.23 no.1
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• pp.35-41
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• 1995

Persimmon boards of 30mm thick were dried, their temperatures were monitored during drying with 490 and 200watt microwave, and the drying efficacy and problems were investigated. The effects of pretreatments such as presteaming and prefreezing were also examined. The persimmon green lumbers of 80% moisture content were dried to 10% for only 50~60 and 110 minutes with 49watt and 200watt microwave, respectively. Severe internal checks were, however, found in all boards. The presteamed boards collapsed on their surfaces earlier than the controls. It may attribute to the high temperature inside boards during microwave drying and the decrease of their internal tensile strength caused by the presteaming treatment. To increase the internal tensile strength of the pretreated boards and to reduce their internal checks, they were air-dried at room temperature. The air-dried boards could be dried to 10% moisture content clearly and free from defects with 200watt microwave. The heating efficiency were also calculated with the maximum weight loss per minute of 490watt and 200watt.

• Journal of the Korean Electrochemical Society
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• v.8 no.1
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• pp.42-46
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• 2005

It has been known that the synthesis of the cathode materials for the lithium rechargeable batteries by the sol-gel process has many advantages over the conventional solid-state method. It has been, however, a continuing issue that new additional steps should be introduced to commercialize this process. In this work, spray drying was introduced to the existing sol-gel process as a continuous mass production method of the pre-heat treatment precursor materials. The precursors of $LiCoO_2$ and $LiNi_{0.8}Co_{0.2}O_2$ were continuously produced through spray drying from the solution containing stoichiometric amount of lithium, cobalt, and nickel sources as well as a chelating agent. The process variables, such as pH of the starting solution, spray drying conditions, and calcination conditions were optimized. The XRD pattern for the synthesized material indicated a good crystallinity with a layered structure.

• 보일러설비
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• s.81
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• pp.101-102
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• 2000