• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.245-246
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• 2012

The analysis of microstructure is essential to understand the material behavior such as shrinkage, strength, and permeability. In this study, three different easy-to-apply specimen preparation methods for the mercury intrusion analysis were chosen, and their effectiveness in removing pore water and thus impeding further hydration was evaluated. As a result, it was found that the direct freeze-drying was the most effective among the three methods.

• Journal of Ginseng Research
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• v.18 no.1
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• pp.60-65
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• 1994

Fresh ginseng of same grade was stored under the 4$\pm$1$^{\circ}C$ and 87~92% RH for 10 weeks. During the storage, an aliquot amount of the ginseng was drawn, freeze dried and chemical constituents and physicochemical parameters were measured. After 10 weeks of storage drying rate and shrinkage of ginseng were 1520% and 9.04%, respectively, mold growth was seen at week 5 and observed for 51.2% of the ginseng week 10. Amylase activity level was elevated at the early stage of storage and decreased to 5% of initial value at week 5. At week 5, the elevated amylase activity was inconcomitant with the appearance of the mold growth. Crude protein contents were increased and decreased, respectively 5 week post storage. No significant changes in crude fat, crude fiber, ash, total sugar, n-butanol extract and ginsenoside were observed. The content of water-extractable substance showed maximum at week 7 to 8. The value of pH was slightly elevated and reducing sugar was increased during the storage. Key words Ginseng storage, physicochemical properties, drying rate, shrinkage, amylase activity.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.236.3-237
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• 2003

Fine particles of water-soluble pharmaceuticals were prepared using a new micronization method, Carbon Dioxide Assisted Nebulization in a Bubble Dryer(CAN-BD). The process utilized mixtures of CO$_2$ in aqueous solution at supercritical conditions to form an emulsion. The aerosols were dried with pre-heated nitrogen, and the drying chamber was operated at near atmospheric pressure. The dry particles were collected on membrane filter at the bottom of the drying chamber. Several processing parameters such as flow rate, temperature, pressure, solid concentration and processing scale were accessed using NaCl, human serum albumin, and granulocyte-colony stimulating factor as model pharmaceuticals. (omitted)

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.4
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• pp.477-484
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• 2010

The majority of currently domestic dried sea foods is holding sanitary safety on storage and distribution, a structural problem to be in quality serious to sun drying. This paper the productive times and the on-site operation that production is fixed are easy, and it have reported the experimental results that carried out on development of a drying system toward field which can keep the highest quality and economy.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.9-14
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• 2010

Several presowing seed treatments have been used to facilitate the seed germination and seedling emergence. The study was performed to design a model of presowing seed treatments in Taraxacum platycarpum. Germination and seedling growth responses to temperature, drying, chilling, $GA_3$ and priming were investigated to know the optimum germination conditions and presowing treatment. The optimum temperature condition for germination and seedling growth were $15{\sim}20^{\circ}C$ at dark condition. The seeds exposed to infra red light, however, did not germinate. The moisture content of seeds dried at $35^{\circ}C$ for 3.5 hours was returned to the level of unimbibed seeds. The germination of seeds dried under dark condition was better than those dried under infra red light. Prechilling treatment imposed for 6 weeks showed higher germination rate than $GA_3$ treatment or priming. In field test, the highest field emergence was observed in the seeds dried after prechilled for 6 weeks and followed by drying followed by $GA_3$ > low temperature > $KNO_3$ priming. Imbibition with 0.1 mM $GA_3$ solution for 2 hours then drying at 35 for 3.5 hour under dark condition was effective to the practical presowing treatment for Taraxacum seeds.

• Mycobiology
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• v.42 no.1
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• pp.59-65
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• 2014

Entomopathogenic fungi are promising pest-control agents but their industrial applicability is limited by their thermosusceptibility. With an aim to increase the thermotolerance of Isaria fumosorosea SFP-198, moisture absorbents were added to dried conidial powder, and the relationship between its water potential and thermotolerance was investigated. Mycotized rice grains were dried at $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, and $40^{\circ}C$ and the drying effect of each temperature for 24, 48, 96, and 140 hr was determined. Drying for 48 hr at $10^{\circ}C$ and $20^{\circ}C$ reduced the moisture content to < 5% without any significant loss of conidial thermotolerance, but drying at $30^{\circ}C$ and $40^{\circ}C$ reduced both moisture content and conidial thermotolerance. To maintain thermotolerance during storage, moisture absorbents, such as calcium chloride, silica gel, magnesium sulfate, white carbon, and sodium sulfate were individually added to previously dried-conidial powder at 10% (w/w). These mixtures was then stored at room temperature for 30 days and subjected to $50^{\circ}C$ for 2 hr. The white carbon mixture had the highest conidial thermotolerance, followed by silica gel, magnesium sulfate, and then the other absorbents. A significant correlation between the water potential and conidial thermotolerance was observed in all conidia-absorbent mixtures tested in this study (r = -0.945). Conidial thermotolerance in wet conditions was evaluated by adding moisturized white carbon (0~20% $H_2O$) to conidia to mimic wet conditions. Notably, the conidia still maintained their thermotolerance under these conditions. Thus, it is evident that conidial thermotolerance can be maintained by drying mycotized rice grains at low temperatures and adding a moisture absorbent, such as white carbon.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.925-931
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• 1997

An attempt was made in this study to investigate the possibility of processing seasoned and semi-dried horse mackerel (Tracharus japonnicus) and to examine its keeping quality, by analyzing the factors such as water content, pH, volatile basic nitrogen, viable cell count, peroxide value, color value and sensory evaluation. For processing of the seasoned and semi-dried product, optimum conditions of drying temperature and drying time were $20^{\circ}C$ and 4 hr, respectively, under $50{\pm}5%$ of relative humidity and 2 m/sec of air blast speed. The shelf-life of the products, vacuum-packaging method in nylon/polyethylene/linear low density polyethylene $(0.015/0.045/0.04\;{\mu}m)$ film bag, was 42 days during storage at $-3{\pm}0.5^{\circ}C$, while that of unpackaged one was only 28 days.

• Applied Chemistry for Engineering
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• v.8 no.1
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• pp.1-7
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• 1997

We show that the usage of the cyclic pressure function in the freeze drying is more effective than the drying rate of the constant pressure process. The ultimate object of this process is to reduce energy costs by shortening the drying time. In this work, the concept of cyclic pressure function to decrease the drying time and the effects of the following factors on drying rate are considered ; pulse type, size in amplitude of pressure, size of intermediate time. Temperature for drying has always been maintained constantly at $20^{\circ}C$ and the pulse type could have found to give useful results than the constant pressure by altering chamber pressure from low pressure to high pressure Also, when the amplitude of the pulse is 0.4 torr and the intermediate time is six hour the drying rate was increased considerably.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.249-253
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• 1995

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred in the initial stage of heating fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after heating. Activation energy of the browning reaction for red ginseng was about 9.0 kcal/mol. Browning reaction of red ginseng was accede- rated with an increase in steaming time, and a great extent of browning reaction occurred between 60-90 min of steaming at 10$0^{\circ}C$. Browning pigments of red ginseng were mostly water soluble subset.

• Applied Biological Chemistry
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• v.24 no.4
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• pp.218-223
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• 1981

This study was conducted to investigate the effects of post-harvest drying method and subsquent storage condition on the quality of garlic bulbs for 10 months from July, 1980 to April, 1981. The 27% weight loss of garlic bulbs by HPHD (hot air post-harvest frying) for 12 days at $40^{\circ}C$ (8hrs/day) was equal to that by NPHD (conventional natural post-harvest drying) for 35 days. But the decay occured 5.5% only in NPHD. During the storage period of garlic bulbs by HPHD, their decay and weight ]oss were less 25.4% and 13.5% in ambient storage, and less 14.2% and 7.5% in low temperature storage than those of NPHD. When garlic bulbs were stored in low temperature, the weight loss and decay were less 20.0% and 22.4% in NPHD, and tess 14.0% and 9.9% in HPHD than those in ambient temperature storage. The Quality of garlic bulbs packed with 0.08mm polyethylene film stored at ambient temperature for 2 months was so poor as to be inedible because of the adverse effect of $CO_2$ and the growth of molds, but in low temperature storage for 10 months it was in good shape showing the weight loss, the decay and the sprouting 2.6%, 3.4% and 26.8%, respectively.