• Title/Summary/Keyword: drying pretreatment

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A Study on the Characteristics of Electric Arc Furnace Slag Concrete According to the Changing of the Pretreatment Method (전처리방법(前處理方法)의 변화(變化)에 따라 제작(製作)된 전기로(電氣爐)슬래그콘크리트의 특성(特性) 연구(硏究))

  • Kim, Nam-Wook;Jeon, Jun-Hong;Bae, Ju-Seong
    • Resources Recycling
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    • v.18 no.4
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    • pp.52-61
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    • 2009
  • Purpose of this research is deducing optimum pretreatment method of electric arc furnace slag from comparing and investigating the properties of electric arc furnace slag and electric arc furnace slag concrete by existing pretreatment method and surface pretreatment method being used by this research. Besides, as the surface pretreatment method, the method of naturally drying for 6 hours after impregnating with an inorganic type silica solution for 1 day was used. From the results, comparing the hot water treatment method, surface treatment method being used by this research is more effective. Therefore, it is judged that surface treatment method is more effective in the decrease of expansibility of electric arc furnace slag and practical use.

Determination of PEG Concentration and Solvent Selection for Freeze-Drying of Highly-Degraded Waterlogged Woods (고함수율 수침고목재의 동결 건조를 위한 PEG 전처리 농도 및 용매 설정)

  • Kim, Soo-Choul;Park, Won-Kyu;Yi, Yong-Hee
    • Journal of Conservation Science
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    • v.9 no.1
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    • pp.40-47
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    • 2000
  • Dimension stability was examined after PEG pretreatment and post freeze-drying treatment in order to determine the PEG(#3350) concentration and solvent for pre-treatment of freeze-drying of highly-degraded waterlogged ash woods(Fraxinus spp.; ca. 5,700 BP) excavated from peat lands at Pyungtack, Kyounggi-do. At the low concentration (<30-40%) of PEG soaking in both water and t-butanol, the weight increases abruptly, but at high concentration (>50%) gradually, consequently, taking longer treatment time. PEG loading was higher in t-butanol solution than in water. However, the best dimesional stability was obtained from freeze-drying after lower PEG solution (40% in water) soaking. Low dimensional stability, found in the samples treated with higher PEG solutions (60%-70% in t-butanol), might come from incomplete freezing and excess PEG absorbing moisture. The samples air-dried after 70% PEG treatment had collapse defects. In conclusion, the use of low concentration (about 40% in water) PEG solution was the most suitable pretreatment for freeze drying of highly-degraded waterlogged ash woods.

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Drying Characteristics of Osmotically Pre-treated Carrots (삼투처리한 당근의 건조 특성)

  • Youn, Kwang-Sup;Choi, Yong-Hee
    • Korean Journal of Food Science and Technology
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    • v.28 no.6
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    • pp.1126-1134
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    • 1996
  • The physical characteristics changes of carrots during drying were studied to minimize the quality degradation by applying improved drying process and pretreatment method. Physico-chemical properties of the product were analyzed, and then, drying mechanisms were explained by diffusion coefficients and drying models. In hot air drying process, the drying and rehydration efficiencies were high at low relative humidity and high temperature. Browning degree and specific volume also showed similar trend to drying efficiency. Diffusion coefficient, which describes moisture transfer, was also high at low relative humidity and at high temperature. It was verified using. Arrhenius equation that drying process was influenced by temperature. It was also observed during experiment that temperature changes were more effective in drying than relative humidity changes. Quadratic model was the most fittable in explaining the process. As a result of analyzing the experimental data with respect to the drying time, the contents of carotene and moisture could be modeled as a polynomial. As the air velocity increased, drying performance and rehydration efficiency increased.

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Active Ingredients and Antioxidant Activities of Salvia plebeia R. Br. According to Pretreatment Conditions (전처리 조건에 따른 배암차즈기(Salvia plebeia R. Br.)의 주요 성분의 함량 및 항산화)

  • Kim, Yong-Joo;Jeong, Ji-Suk;Park, No-Jin;Go, Geun-Bae;Son, Byeong-Gil
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.12
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    • pp.1948-1953
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    • 2014
  • This study examined changes in antioxidant activity as well as contents of rosmarinic acid, homoplantaginin, and luteolin, which is the main substance of Salvia plebeia R. Br. (SPR) known to have anti-inflammatory efficacy, according to drying, blanching, and fermentation conditions. Rosmarinic acid content was 16.42 mg/g upon hot-air drying and 10.19 mg/g upon hot-air drying after blanching, and there was no significant difference in the case of leaf and root freezing or cold-air drying. Rosmarinic acid content was 8.69 and 8.15 mg/g in the case of air-drying in the shade and freeze-drying, respectively, and decreased to 0.05 mg/g or undetected after fermentation. SPR processed by freeze-drying, cold-air drying in the shade, and hot-air drying showed ABTS radical scavenging ability over 98.5% at a concentration over $500{\mu}g/mL$ as well as excellent radical scavenging ability of 87.3% in the case of hot-air drying after blanching. Root showed lower ABTS radical scavenging ability than leaves. SOD-like activity was measured to be 6.1~27.8% at a concentration of $1,000{\mu}g/mL$, which was significantly difference from ABTS radical scavenging ability. As rosmarinic acid and homoplantagine, an anti-inflammatory material contained in SPR, are almost undetectable after oxidation fermentation during processing, hot-air drying after blanching or drying seems to be suitable to develop SPR as a functional substance.

Quality Properties of Dried Melon with Different Pretreatments (전처리 방법이 건조참외의 품질에 미치는 영향)

  • 김지강;정석태
    • Food Science and Preservation
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    • v.4 no.2
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    • pp.147-153
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    • 1997
  • Oriental melon has been increased in production amount, but its processed food was not made in spite of the fact that shelf-life of the fresh fruit is short. This study was carried out to develop a dried product with no use sulfur treatment. Fresh melons were peeled, cut into 6 pieces, and soaked to the following pretreatments soaking in sugar syrup(SS), sodium chloride(SC), ascorbic acid(AA) and sodium polyphosphate(SP). After preatreatments the melon pieces were dried by hot air drying at 5$0^{\circ}C$ for 9 and 12 hours, and the dried melons were air blown at $25^{\circ}C$ for 1 day. The dried samples were evaluated for moisture content, texture, rotor, and sensory quality. The moisture content of dried melons soaked in SS and SC were lower than those that were soaked in AA and SP after hot air drying. The melons dried for 12 hours were high in hardness, gumminess, chewness and adhesiveness and excellent in sensory evaluation compared to 9 hours. The "L" value of SS was higher and the "a" value was lower in Hunter color. And SS treatment inhibited browning of the dried melon and improved sensory characteristics in color, flavor, texture and taste. Sucrose concentration had no significant effect on color, hardness and sensory score in banal product. The combination of SS with SP represented a highly effective antibrowning treatment for the dried melon and the product was kept in good color for 3 months at room temperature.at room temperature.

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Quality Characteristics of Ginger and Ginger Pomace Powder according to Pretreatment Methods (전처리 방법에 따른 생강과 생강박 분말의 품질 특성)

  • Yun-Jeong Jo;Jong-Kug Lee;So-Yeon Lee;Jung-Il Ju
    • The Korean Journal of Food And Nutrition
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    • v.37 no.4
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    • pp.180-188
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    • 2024
  • In this study, chemical properties and functional ingredients of ginger and ginger pomace discarded after juice were analyzed. Ginger and ginger pomace were subjected to hot air drying, steaming, followed by hot air drying, soaking in vitamin C for 1 hour and 3 hours. When soaked in vitamin C for 3 hours, the moisture content was highest at 9.2% for ginger and 7.3% for ginger pomace. Among inorganic ingredients, the potassium (K) content was high at 2,633.6 mg% in hot air-dried ginger after steaming and at 1,584.3 mg% in ginger pomace. Total flavonoid content of ginger pomace was high at 67.3 mg/g when soaked in vitamin C for 3 hours. Gingerol content was the highest at 9.8 mg/g when ginger was dried with hot air. It was 10.5 mg/g in ginger pomace. After ginger pomace was steamed and dried with hot air, shogaol content was as high as 2.0 mg/g.

Development of wast vinyl pretreatment system by dry method (폐비닐의 건식 전처리시스템 개발)

  • Lee Hyun-Yong;Lee Jae-Kyung;Ryoo Byung-Soon
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.69-70
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    • 2006
  • Waste vinyl tretreatment system has been developed by the joint project between KIMM and Woosung Co. General process for removal of impurities from waste vinyl is consisted of feeding, separating, cutting, washing, drying and recovering impurities. However, there are problems such as wastewater when washing of waste vinyl. In order to solve these problems we have developed new dry type cleaning system.

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Effects of pretreatments and storage temperature on the quality of lotus leaves (연잎의 품질특성에 미치는 전처리 방법과 저장온도의 영향)

  • Choi, Jeong-Sil;Kong, Moon-Hee;Yeo, Soo-Hwan;Choi, Han-Seok;Jeong, Seok-Tae
    • Food Science and Preservation
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    • v.23 no.2
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    • pp.155-161
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    • 2016
  • This study aimed to investigate the effects of pretreatments blanching, roasting, drying, and storage temperatures ($25^{\circ}C$, $4^{\circ}C$ and $-10^{\circ}C$) on their quality of lotus leaves. As a result, the lotus leaves retained a good appearance when stored at $25^{\circ}C$ for 5 days, $4^{\circ}C$ for 30 days, and $-10^{\circ}C$ for 90 days, regardless of the pretreatment used. At the same storage temperatures, pH, soluble solids, total acid content, polyphenols, and microorganisms were significantly different among the pretreatments (p<0.05). Soluble solids, pH, and total acid contents were not significantly different for the same pretreatments at different storage temperatures. However, the polyphenol, oxalic acid, and tartaric acid contents of lotus leaves were significantly different after drying and blanching treatments. In particular, it was shown that polyphenol content of the lotus leaf was affected by both pretreatment and storage temperature. In conclusion, the lotus leaves appeared in good condition until 5 days at $25^{\circ}C$, 30 days at $4^{\circ}C$, and 90 days at $-10^{\circ}C$, regardless of the pretreatment while influenced by storage temperature.

Characteristics of the Radio-Frequency/Vacuum Drying of Heavy Timbers for Post and Beam of Korean Style Housings Part II : For Korean red pine heavy timbers with 250 × 250 mm, 300 × 300 mm in cross section and 300 mm in diameter, and 3,600 mm in length

  • Lee, Nam-Ho;Zhao, Xue-Feng;Shin, Ik-Hyun;Park, Moon-Jae;Park, Jung-Hwan;Park, Joo-Saeng
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.2
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    • pp.132-139
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    • 2011
  • This study examined the characteristics of radio-frequency/vacuum dried Korean red pine ($Pinus$ $densoflora$) heavy timbers with 250 ${\times}$ 250 mm (S), 300 ${\times}$ 300 mm (L) in cross section and 300 mm in diameter, and 3,600 mm in length, which were subjected to compressive loading after a kerf pretreatment. The following results were obtained : The drying time was short and the drying rate was high in spite of the large cross section of specimens. The moisture gradient inall specimens was gentle in both longitudinal and transverse directions owing to dielectric heating. The shrinkage of the width in the direction perpendicular to was 21 percent ~ 76 percent of that of the thickness of square timbers in the direction parallel to the mechanical pressure. The casehardening for all specimens was very slight because of significantly reduced ratio of the tangential to radial shrinkage of specimens and kerfing. The surface checks somewhat severely occurred although the occurrence extent of the surface checks on the kerfed specimens was slight compared withthat on the control specimen.

Preparation of Barley Leaf Powder Tea and Its Quality Characteristics (보리잎 분말차의 제조와 그 품질특성)

  • Kim, Dong-Chung;Kim, Dong-Won;Lee, Sung-Dong;In, Man-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.6
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    • pp.734-737
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    • 2006
  • This study was carried out to establish the manufacturing process of barley leaf powder tea. The optimal manufacturing process among many trials was determined with sensory evaluation. Finally established process and operation conditions were as follows: pretreatment (cutting and washing), steaming ($100^{\circ}C$, 30 sec), primary drying and roasting ($130^{\circ}C$, 40 min), rolling (RT, 25 min), middle drying and roasting ($60^{\circ}C$, 30 min), final drying and roasting ($55^{\circ}C$, 25 min), drying ($60^{\circ}C$, 20 min), roasting ($85^{\circ}C$, 20 min), and powdering (120 mesh). The barley leaf powder tea produced by this process mainly consisted of dietary fiber (33.8%), amino acids (12.9%), minerals (4.7%) and ${\beta}-carotene$ (6.9 mg%).