• Title/Summary/Keyword: hot air dry

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The Drying Characteristics of Cooked-Ginseng Root and Its Shrinkage during Dehydration (증자인삼(蒸煮人蔘)의 건조특성(乾燥特性)과 건조(乾燥)에 수반(隨伴)하는 삼근(蔘根)의 수축(收縮))

  • Chun, Jae-Kun;Park, Hoon;Suh, Chung-Sik
    • Applied Biological Chemistry
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    • v.28 no.3
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    • pp.167-173
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    • 1985
  • Hot air drying characteristics of six year old cooked ginseng root at temperature ranges of $55{\sim}75^{\circ}C$ under 1.8m/sec air velocity and shrinkages accompained were investigated. Drying time to reach equilibrium moisture content of the root takes from 20 to 30 hours, depending on the subjected drying temperatures and root sizes. Drying curve shows that it has two or three falling stages and drying constant are continuously changed. Higher drying constant was observed both at early and late stages of drying. Shrinkage ratio of length, diameters, surface area and volume of the root were 13.0, 39.8, 47.7 and 68.5%, respectively, after 40 hours dry at $55^{\circ}C$. The most of shrinkage was observed at early drying stage.

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Influence of Mixtures and Curing Conditions on Strength and Microstructure of Reactive Powder Concrete Using Ternary Pozzolanic Materials (배합 및 양생조건이 3성분계 포졸란재를 이용한 RPC의 강도발현 특성에 미치는 영향)

  • Janchivdorj, Khulgadai;Choi, Seung-Hoon;So, Hyoung-Seok;Seo, Ki-Seog;So, Seung-Young
    • Journal of the Korea Concrete Institute
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    • v.25 no.4
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    • pp.457-465
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    • 2013
  • This study discussed the influence of mixtures and curing conditions on the development of strength and microstructure of RPC using ternary pozzolanic materials. Through pilot experiment, various RPC was manufactured by adding single or mixed ternary pozzolanic materials such as silica fume, blast furnace slag and fly ash by mass of cement, up to 0~65%, and cured by using 4 types of method which are water and air-dried curing at $20^{\circ}C$, steam and hot-water curing at $90^{\circ}C$. The results show that the use of ternary pozzolanic materials and a suitable curing method are an effective method for improving development of strength and microstructure of RPC. The unit volume of cement was greatly reduced in RPC with ternary pozzolanic materials and unlike hydration reaction in cement, the pozzolanic reaction noticeably contributes to a reduction in hydration heat and dry shrinkage. A considerable improvement was found in the flexural strength of RPC using ternary pozzolanic materials, and then the utilization of a structural member subjected to bending was expected. The X-ray diffractometer (XRD) analysis and Scanning Electronic Microscope (SEM) revealed that the microstructure of RPC was denser by using the ternary pozzolanic materials than the original RPC containing silica fume only.

Climate Change Impacts in Natural Resources and Livestock in Mongolia Climate

  • Batima, P.;Natsagdorj, L.;Bayarbaatar, L..;Bolortsetseg, B.;Natsagsuren, N.;Erdenetsetseg, B.
    • The Korean Journal of Quaternary Research
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    • v.18 no.2 s.23
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    • pp.103-104
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    • 2004
  • This paper discuss some results of observed changes of meteorological elements as temperature, precipitation and some extreme indexes in Mongolia. Mongolia is one of the largest landlocked countries in the world. The climate is characterized by a long lasting cold winter, dry and hot summer, low precipitation, high temperature fluctuation and relatively high number of sunny days per year. During last 60 years the annual mean air temperature has risen $1.66^{\circ}C$. Intensive warming of > $2^{\circ}C$ was observed at higher altitudes of high mountains when warming of < $1^{\circ}C$ was observed the Domod steppe and the Gobi Desert. Heat Wave Duration have statistically significant risen trend with increaded number of days by 8-18 at significance level of 95-99.9% depending on geography and Cold Wave Duration have shortened by 13.3 days significance level of 95-99%. In general, by the amount of precipitation, Mongolia falls in semi-arid and arid region. It is 300-350 mm in the high mountain regions while it is only 50-150 mm in Gobi Desert regions. The changes of annual precipitation have very localized character i.e.decreasing at one site and increasing at a sit nearby. Annual precipitation decreased by 30-90 mm in the northern-central region and increased by 2-60 mm in the western and eastern region. The magnitude of alteration changes in precipitation regardless increasing or decreasing is 5-25%. A trends, significant at the level of 90%, found where changes are more than 40 mm or more than 15% of annual mean value. Moreover, the soil moisture resources was decreased in the last 40 years. Specially, moisture contents of the top soil have decreased 2 times(N. Natsagsuren, 2002). Months of June and July in Mongolia is the year that moisture is not inhibiting vegetation growth. Unfortunately, its also found that moisture in this time tends to decrease. Increased temperature, decreased precipitation and soil moisture are most likely resulted in occurences of more intense drought spells that have taken place during the recent years. Intimately, these changes have considerable impact on livestock in Mongolia.

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Changes in Quality by Drying Methods, Different Storage Conditions and Package Mediums for Established GAP Guide Book in Scutellaria baicalensis Georgi (황금 GAP 지침 설정을 위한 건조방법, 저장조건 및 포장재료에 따른 품질변화)

  • Kim, Myeong Seok;Kim, Kil Ja;Choi, Jin Gyung;Kwon, Oh Do;Park, Heung Gyu;Kim, Hyun Woo;Kim, Seong Il;Kim, Young Guk;Cha, Seon Woo;Shim, Jae Han
    • Korean Journal of Medicinal Crop Science
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    • v.25 no.2
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    • pp.89-94
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    • 2017
  • Background: The purpose of improving the quality of oriental medicinal herbs is to contribute to the improvement of the income of farm. The present study investigated the effect of reasonable drying methods, different storage conditions and packageing materials on quality and stability of Scutellaria baicalensis Georgi and for developing GAP (good agricultural practice) guide book. Methods and Results: Three methods of drying Scutellaria baicalensis roots produced over two years were used to estimate loss rate owing to drying, storage, and packaging. The methods of drying were categorized into natural drying (36 - 60 h by sunshine), drying with heat dryer (2 - 10 h), or drying with gas bulk dryer (2 - 10 h). After cleaning, and initial drying for a few days under controlled temperature conditions, the second phase of drying was carried out at 35, 45 and $55^{\circ}C$. Changes in hunter color values and quality under the two studied storage treatments (at $20^{\circ}C$ indoors and at $4^{\circ}C$ in a refigerator) were evaluated. Storage period for 60, 120, and 180 days in three packaging materials, PE (polyethylene package), PP (polypropylene gunnysack), and WP (watertight packing paper) were studied. Conclusions: Initial cleaning, reasonable gas drying and hot air drying, and drying in an oven at 35 and $45^{\circ}C$ after cutting the roots resulted in the lowest loss rates in S. Baicalensis root. Hunter color valuse indicated that stroage of dry roots at room temperature was better than PP packaging, and that cold stroage was better than PE packaging for long-term stability.

Utilization of Chitin Prepared from the Shellfish Crust 2. Effect of Chitosan Film Packing on Quality of Lightly-Salted and Dried Horse Mackerel (갑각류부산물을 이용한 키틴의 제조 및 이용에 관한 연구 2. 키토산필름포장이 반염건(半鹽乾) 전갱이의 가공 및 저장 중 품질에 미치는 효과)

  • AHN Chang-Bum;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.1
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    • pp.51-57
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    • 1992
  • The preservative effect of chitosan film packing on quality of lightly-salted and dried horse mackerel was studied. In preparation of chitosan film, blue crab shell chitosan was dissolved in dilute acetic acid$(1.0\%,\;v/v)$, filtered, and spreaded on plastic plate and dried at $50\pm2^{\circ}C$. The chitosan film thus obtained was neutralized with 1.0N NaOH for 2 hrs and dried at room temperature after washing several times with distilled water. The lightly-salted and dried horse mackerel product was prepared by drying for 4 hrs at $40\pm2^{\circ}C$ in hot air dryer after packing with the chitosan film. During storage at $5.0\pm0.5^{\circ}C$, moisture content of the product was higher than that of the reference, but contents of VBN(volatile basic nitrogen) , amino nitrogen, and TMA of the product on dry basis were lower than those of the reference. Viable cell count, TBA value, and peroxide value of the product were also lower than those of the reference. Judging from the result of sensory evaluation, the chitosan film packing in the storage of lightly-salted and dried horse mackerel was remarkably elongated shelf-life of the product. From the results of chemical and sensory evaluation, it was concluded that chitosan film packing was an effective method for retaining the quality of lightly-salted and dried horse mackerel.

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Effect of Drying Methods on Physicochemical Properties of Agar (건조 방법이 한천의 물리${\cdot}$화학적 특성에 미치는 영향)

  • KIM Oc-Do;KIM Yuck-Yong;LEE Nahm-Gull;CHO Young-Je;LEE Kang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.5
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    • pp.681-688
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    • 1996
  • To investigate the effort of drying methods on the physicochemical properties of agar, gel strength, viscosity, melting and setting point, and phase transition by differential scanning calorimetery (DSC) during its heating were determined. In addition the structural differences of agar powder by scanning electron microscope (SEM) was examined. The most shortest onset temperature of gel strength increase was extruding method among any other methods. Viscosity of agar with hot air method, 400.00 cps at $45^{\circ}C$, was markedly increased, but with spraying and extruding ones were little change. The melting and setting point, and the temperature for maximum endothermic and enthalpy for agar with extruding one, $80.01^{\circ}C,\;36.05^{\circ}C\;and\;61.72^{\circ}C,\;0.73\;cal/g$, respectively, were lowest among the drying ones. But in the case of reheating after gelling, there were little change in all methods. Observing the surface structure of agar with SEM, extruding method showed the most unstable with absorptive property.

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Changes on Physicochemical Properties of Panax ginseng C. A. Meyer during Repeated Steaming Process (증숙 횟수에 따른 고려인삼의 이화학적 특성 변화)

  • Hong, Hee-Do;Kim, Young-Chan;Rho, Jeong-Hae;Kim, Kyung-Tack;Lee, Young-Chul
    • Journal of Ginseng Research
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    • v.31 no.4
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    • pp.222-229
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    • 2007
  • Changes on physicochemical properties of fresh Korean ginseng during repeated 9 times steaming processes, steaming $90{\sim}95^{\circ}C$ for $1{\sim}3\;hr$ followed by hot air-drying at $50^{\circ}C$ for $36{\sim}48\;hr$, were investigated. The water contents decreased from 73.4% of fresh ginseng to 13.7% finally. The final yields in bases of total weights and dry matter were 21.0% and 79.0%, respectively. As the times of steaming processes increased, lightness (L value) decreased and redness (a value) increased in color of ginseng powder. Browning index also rapidly increased after 3 times of steaming process in particular. Total water soluble sugar contents decreased from 55.4% in fresh to 38.6% in final processed ginseng, but acidic polysaccharide contents increased by about 50% with increasing times of steaming process. Total phenolic compound contents significantly increased with repeated steaming processes especially after 5 times of steaming processes and crude saponin contents also increased in some degree. In the case of major ginsenosides, the contents of $Rb_1$, $Rb_2$, $Rg_1$, Re (representative ginsenosides in fresh ginseng) decreased, but those of $Rg_2$, $Rh_1$, $Rg_3$ (unique ginsenosides in red ginseng) increased after especially 5 times of steaming processes.

Development of Composite Flours and Their Products Utilizing Domestic Raw Materials -Part V. The Preperation of Noodles made of Composite flours- (국산원료(國産原料)를 활용(活用)한 복합분(複合粉) 및 제품개발(製品開發)에 관한 연구(硏究) -제5보 복합분(複合粉)을 이용(利用)한 면류(麵類)의 제조(製造)-)

  • Kim, Hyong-Soo;Oh, Jung-Suk
    • Korean Journal of Food Science and Technology
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    • v.7 no.4
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    • pp.187-193
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    • 1975
  • A supplemental effect of Undaria Pinnatifida extract on the composite flour prepared from a blend of wheat, barley, sweet potato, potato, and defatted soybean flours was studied in terms of binding properties, cooking test, and sensory analysis. Dry noodle of the composite flour was made by the conventional method and air dried. Instant noodle was prepared in a hot vegetable oil bath after the noodle was made. The standard was made of wheat flour only. 1. The noodle prepared with composite flour (wheat flour : barley flour, 5 : 5) and Undaria Pinnatifida extract (1 or 2%) showed same results of cooking and sensory tests as well as properties of texture as the standard. 2. The mixture of wheat, barley and defatted soybean flour (10%) had a less efficient binding capacity with Undaria Pinnatifida extract. The binding effect was, however, significantly improved with the wheat and barley flour mixture with either sweet potato or potato flour. 3. The instant noodle prepared with the composite flour (either barley, or sweet potato, or potato was mixed with wheat flour up to 70% separately) and hydroxypropyl methyl cellulose (1% as final) showed the higher oil absorption and the sensory results were the same as the standard. Nevertheless, the binding properties and cooking quality were less efficient.

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Comparative Study on the Control and Removal of Formaldehyde for the Urea-formaldehyde Resin Bonded Plywood -Adhesive control- (요소수지접착합판(尿素樹脂接着合板)의 유리(遊離)포름알데히드 방산(放散)제거 및 조절방법에 대한 비교연구(比較硏究))

  • Lee, Hwa-Hyoung
    • Journal of the Korean Wood Science and Technology
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    • v.9 no.3
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    • pp.16-23
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    • 1981
  • This study has been carried out to make a comparative study for the adhesive control methods specifically developed for application to formaldehyde. The method for formaldehyde determination used in this report is the improved chromo tropic acid determination. The results are summarized as follows: 1. The soaking treatment in aqueous solution of urea wok the most scavenging effect on the formaldehyde release from a plywood sample glued with a urea formaldehyde adhesive, and other removal treatment such as resorcinol, albumine-, and hardener-treatment gave significant reduction too. 2. In glue shear strength of dry test, 2% of resorcinol treatment and soaking treatment showed the highest strength and all the other treatment met the standard, but in hot water soaking test, 2% of resorcinol treatment gave the best results, on the other hand, adding the hardener showed the lowest strength and failed in meeting the standard. 3. Air dried moisture content of all treated plywood met the standard which calls for 13% or bellow. 4. In this comparative study, we can make a strong combination each other or go into the details of one treatment for the best result through the more study.

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The Effect of Cellophane Film Packing on Quality of Semi-Salted and Dried Mackerel during Processing and Storage (셀로판 필름보장이 반염건고등어의 가공 및 저장중의 품질에 미치는 효과)

  • 이응호;안창범;김복규;이채한;이호연
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.2
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    • pp.139-147
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    • 1991
  • The preservative effect of cellophane film packing on the quality of semi-salted and dried mackerel was studied. The product(P) of semi-salted and dried mackerel was prepared from raw mackerel by filleting, cleaning, soaking in 15%9v/w) salt solution for 30min, draining, packing with cellophane film (PT# 300, thickness:$20{\mu}{\textrm}{m}$) and drying for 4 hrs at $40^{\circ}C$ in hot air dryer. The product (C) was also prepared without cellophane film packing after draining. The product (C) and (P) were stored at $5.0{\pm}0.5^{\circ}C$. After processing and during storage, moisture content of product (P) was higher than that of product (C), but contents of VBN(volatile basic nitrogen), amino nitrogen and TMA of product (P) on dry basis were lower than those of product (C). Viable cell count, TBA value, peroxide value and decreasing rate of polyenoic acid of product (P) were also lower than those of product (C). In sensory evaluation, the shelf life of product (C) was about 9 days and that of product (P) was about 14 days. From the results of chemical and sensory evaluation, it was concluded that cellophane film packing was a good condition for preserving the quality of semi-salted and dried mackerel.

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