• Journal of Korea Foresty Energy
• /
• v.21 no.3
• /
• pp.10-17
• /
• 2002

This study was carried out to investigate a heat treatment condition and suitable drying schedule of bamboo material(Phyllostachys nigra var. henonis) for a vertical flute with small-notched bamboo. It is very important to prevent drying defects during its drying process. We investigated the effort of heat treatment the most suitable drying schedule for small-notched bamboo vertical flute without drying defects in this research. A direct heat treatment method and drying conditions of 3($20^{\circ}C$ 65%, $40^{\circ}C$ 40%, and dry at air condition) were applied to the Bamboo specimen that felled in several areas for a month. The result suggested that the most suitable drying schedule with the less split and the shortest time was to dry at $40^{\circ}C$, 40% condition and it was useful to direct heat-treatment because of reducing the number and size of split during drying bamboo.

• Journal of Bio-Environment Control
• /
• v.27 no.4
• /
• pp.356-362
• /
• 2018

Hot pepper is a kind of seasoning vegetables, which is a major item in the Korean vegetable market. Since the use of hot pepper is processed into pepper powder, which is a powder form of dried hot pepper, improvement of quality and productivity of dried hot pepper is important. Therefore, this experiment was conducted to suggest proper drying method by comparing the changes of hot pepper powder ingredients considering production cost according to the drying method. As a drying method, we used sun drying and heat drying which are widely used in practice. We also compared the productivity and quality of dried hot pepper by applying a dehumidifying drying method using a dehumidifier. Drying rate of hot pepper was highest of 85.1% at heat drying. Accordingly moisture content of hot pepper powder was lowest of 13.5% at heat drying. The American Spice Trade Association (ASTA) color value, which influenced the coloring of red pepper, showed higher in heat drying and dehumidified drying treatment than the sun drying treatment. The content of capsaicinoids was higher at sun drying treatment than that of at both heat drying and dehumidified drying treatments. The content of sugar was higher at heat drying and dehumidified drying treatment where drying time was relatively short than that of sun drying treatment. Also, there was no significant difference in sugar content between the two treatments. The production cost of dried hot pepper with dehumidified drying was 9.9% more efficient than heat drying. Through this study, it was found that heat and dehumidified drying method were effective in increasing sugar content and coloring of hot pepper powder. In order to improve the capsaicinoid content of red pepper, it is considered that appropriate drying temperature and drying time should be added in the process of heat drying and dehumidified drying.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.43 no.5
• /
• pp.17-26
• /
• 2011

Drying behavior and physical properties of HwBKP, SwBKP, and OCC handsheets depending on kneading, refining and wet pressing were analyzed. The maximum drying shrinkage velocity was newly adopted to verify the effect of mechanical treatment of pulps by evaluating drying behavior according to varying the kneading, refining and wet pressing treatments. Those various treatments were changed to evaluate the relationship between the maximum drying shrinkage velocity and handsheets properties. When the drying shrinkage and the maximum drying velocity increased by refining and wet-pressing, handsheets strength was increased. The maximum drying shrinkage velocity showed higher correlation with physical properties of paper than WRV at different refining loads at SwBKP and mixed pulp. At high wet-web dryness, drying shrinkage, the maximum drying shrinkage velocity and strength properties of handsheet were increased. It meant that drying shrinkage behavior was highly affected by not only fibers' shrinkage but also fiber bonding. Kneading pre-treatment for KOCC and SwBKP effectively modified fiber properties and increasing paper strength and drying shrinkage. The effect of kneading pre-treatment was also confirmed by the maximum drying shrinkage velocity. Strength properties of mixed pulp handsheets were not increased by the kneading pre-treatment, although the maximum drying shrinkage velocity and WRV was increased. It meant that fibers network bonding of HwBKP was limited because of ves sels and ray cells' interference for bonding. Therefore in order to improve paper strengths containing HwBKP by mechanical treatments, interference of vessels and ray cells for fiber bondings should be carefully controlled.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.20 no.1
• /
• pp.67-74
• /
• 2018

This experiment was conducted to develop a healthy tea by fumigation, low temperature drying, drying and instant immersion using flowers of Robinia pseudoacacia L. that bloom in May in all regions of Korea. The drying was drying after fumigation treatment, low temperature drying, drying and instant immersion. The color of the flowers, beverage color, the sugar content, and the taste of the beverage were measured after changing the weight of the flowers. The change in the weight of flower tea was 11% ~ 12.5% of the body weight. The change in the color of the flowers appeared to be the lightest brown in the treatment of drying, and the other treatment area became turbidity white. The color of the beverage was yellowish from the tea treated with drying and became pale yellow when fumigation, low temperature drying and instant immersion. Sugar content was highest at 2.9brix from the drying and 2.6-2.7brix at the other three treatments. The taste was the best in the drying treatment, and the instant taste dipped in the tastes.

• Journal of the Korean Wood Science and Technology
• /
• v.44 no.5
• /
• pp.677-684
• /
• 2016

This study was carried out to confirm the effects of the knife-incising and longitudinal kerfing treatment on high-temperature drying characteristics of red pine square timber with dimensions of thickness 15 cm. The range of final moisture content was investigated 5.6% to 7.5% after drying. The differences did not exist in the moisture content and distribution according to the pretreatment condition. In the case of longitudinal kerfing treatment, the surface check occurrence was reduced than the control. In addition, the twist had a tendency to decrease due to the longitudinal kerfing treatment. The knife-incising and longitudinal kerfing treatment were investigated to be ineffective on internal checks and drying shrinkage.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.34 no.2 s.115
• /
• pp.36-43
• /
• 2006

This study was carried out to determine the ways in which drying improves and develops dredged soils which exist widely in the lowlands of Korea. Before drying there were large variations in the fundamental physico-chemical properties of dredged soils collected from different places. In the sample soils, saturated hydraulic conductivity decreased gradually with an increase in bulk density with the exception that in air-dried soils a reverse trend was observed. Also in the sample soils, the sedimentation volume and the consistency limits decreased gradually with the decrease in soil water content after the air-drying treatment. The porosity of the sample soils decreased from $0.67{\sim}0.87m^3/m^3\;to\;0.58{\sim}0.66m^3/m^3$ and the liquid-phase range decreased from $0.41{\sim}0.83m^3/m^3\;to\;0.29{\sim}0.71m^3/m^3$. The solid-phase range of sample soils increased $0.13{\sim}0.33m^3/m^3\;to\;0.24{\sim}0.37m^3/m^3$ same as above with air-drying treatment. In conclusion the air-drying treatment caused an irreversible effect on some physical properties. Accordingly, these facts indicate that the effects of air-drying treatment on these properties are considered to be resulted from irreversible changes in the structural status of the sample soils.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.1
• /
• pp.11-16
• /
• 2007

This study was carried out to investigate the effect of Vapor-dam treatment on drying drying rates, prevention of checks and V-shaped split during air circulating oven drying bamboo (Phyllostachys pubescens Mazel et Z) tube. It was shown that the drying time from green to around 7~8 % of moisture content was required less as drying schedule was more severe, and distinctly dominated by the drying rate during the initial drying stage. Area shrinkages in cross section and thickness shrinkages measured during air circulating oven drying test were very large. Surface checks and V-shaped splits were occurred in untreated samples just after the beginning of drying, while sixty seven percentages of all the Vapor-dam treated samples could be produced without drying defects. The V-shaped splits occurred in the Vapor-dam treated samples were influenced more by the sealing of the vapor evaporation through the cross section than drying schedule.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.1
• /
• pp.17-26
• /
• 2007

This study was conducted to investigate the effects of End-coating (CO) treatment and Vapor-dam (V) treatment on the air circulating oven drying characteristics of green stock (Paulownia tomentosa) for drum. The reduction of the weight of specimens was greatly displayed in order of control (C-NC) treatment, End-coating (C-CO) treatment, Vapor-dam (V-NC) treatment and Vapor-dam/End-coating (V-CO) treatment after the beginning of drying. The V-CO treated specimen showed smoother temperature gradient compared with the V-NC treated specimen throughout whole drying stage and there was little temperature gradient between the inner and outer part of the cylindrical stock. The C-CO treated specimen showed higher value of vapor pressure in both the inner and outer part of the cylindrical stock until the middle stage of drying, while after the middle stage of drying only the inner part of the cylindrical stock presented higher value compared with the C-NC treated specimen. The distribution of the absolute vapor pressure of the V-CO treated specimen was similar to that of the V-NC treated specimen during the initial stage of drying. However, the former showed a large distribution in order of the hollow, the outer part, the inner part of the cylindrical stock after the initial stage of drying, which was entirely different model of distribution from that of the V-NC treated specimen. Surface checks and ring failures were not observed for all of the specimens, while end checks were severely occurred for the C-NC treated specimen and the V-NC treated specimen.

• Food Science and Preservation
• /
• v.4 no.1
• /
• pp.69-75
• /
• 1997

Peony is a medicinal herb which have utilized widely as chineses medicine. The paeoniflorin is the predominant component In peony root, monoterpene glucoside containing pinane structure. The effective components were extracted with the cold water from the intact peony roots, and effectively extracted with 70% ethanol from the dry powder of peony roots. The changes of paeoniflorin contents were investigated during the drying process of peony roots and processing of peony extract by the heat-treatment. Air-drying was the best condition for the preservation of paeoniflorin content among the drying processes of peony roots. But convective drying at 6$0^{\circ}C$ was recommended for the drying process of peony roots in large scale. The paeoniflorin in peony extracts was not destroyed by the treatment at 6$0^{\circ}C$ and 8$0^{\circ}C$ for 5 hrs, but destroyed 30%, 28% and 40% of paeoniflorin by treatment at 10$0^{\circ}C$ for 5 hrs, 115$^{\circ}C$ and 121$^{\circ}C$ for 10 minutes, respectively. The paeoniflorin was continueously extracted for 4 hrs from the dry pieces of peony roots(0.5$\times$0.5$\times$0.5cm) in boiling water but destroyed gradually after 4 hrs at 10$0^{\circ}C$. Paeoniflorins in 70% ethanol extracts of peony root were not destroyed at all in the process of concentration to dry powder at 60"C on vacuum.cuum.

• Korean journal of food and cookery science
• /
• v.13 no.5
• /
• pp.635-638
• /
• 1997

Dried raddish leaves were prepared by using three different pre-treatment methods (shady sun-drying, freezing after blanching, and shady sun-drying after blanching). Then, the retention of minerals in dried raddish leaves was determined. It was shown that the retention of most minerals (Na, K, Fe, Ca, Mg) except P was higher when shady sun-drying method was used. The retention of P was shown to be the lowest when freezing after blanching method was used.