• 제목/요약/키워드: moisture-heat treatment

검색결과 151건 처리시간 0.026초

주정처리와 수분-열처리 떡볶이 떡의 저장기간에 따른 품질 특성 (Quality Characteristics of Tteokbokki Tteok after Ethanol and Heat Moisture Treatments During the Storage Periods)

  • 최해연;김진성;고은성;우혜은;박종대;성정민
    • 한국식생활문화학회지
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    • 제36권3호
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    • pp.325-332
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    • 2021
  • This study sought to investigate the effects of heat-moisture treatment (HMT) and ethanol treatment (EOH) for improving the quality and storage stability of Tteokbokki Tteok. The quality characteristics were evaluated by moisture, pH, color, texture profile analysis, and observing the microbial properties after the heat-moisture treatment or ethanol treatment. As the storage period increased, the moisture content of Tteokbokki Tteok tended to decrease except for the HMT group (p<0.05) while the pH did not show significant variation except for the EOH group (p<0.05). While measuring the color, the L-value tended to increase in all groups during the storage period. The a-value and the b-value showed the highest values in the HMT group and the control (CON) group, respectively. In the texture profile analysis, all groups showed a significant tendency to increase levels of hardness and chewiness as the storage period increased (p<0.05). The HMT group showed an increase in hardness and adhesiveness, which are characteristics of the HMT treatment. The results of examining the microbial properties of Tteokbokki Tteok showed that the total microbial count in the HMT group was 4.52 on the 8th day of storage, which was lower than the level in the CON group and the EOH group on the 4th day of storage. Yeast and mold were not measured during the storage period. Thus the results of this study showed that when manufacturing Tteokbokki Tteok, the heat-moisture treatment of rice powder increased the storage stability by delaying microbial growth and also had positive effects on quality.

소나무재선충병 피해를 받은 곰솔 원목의 열처리 소요시간 예측 (Prediction of Heat-treatment Time of Black Pine Log Damaged by Pine Wilt Disease)

  • 한연중;서연옥;정성철;엄창득
    • Journal of the Korean Wood Science and Technology
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    • 제44권3호
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    • pp.370-380
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    • 2016
  • 제주도 지역에서 소나무재선충병 피해를 받은 곰솔 원목의 이용확대를 위하여 열처리를 수행하였다. 열처리는 처리 원목의 중심부가 소나무재선충의 사멸온도인 $56^{\circ}C$를 30분간 유지하여야 한다. 곰솔 원목의 초기함수율과 말구지름은 각각 46% ~ 141%, 180 mm ~ 500 mm의 범위이고, 기본비중과 전건비중은 각각 0.47, 0.52이었다. $105^{\circ}C$ 조건에서 함수율과 말구지름에 따라 열처리에 소요되는 시간은 7.7 h ~ 44.2 h의 범위로 측정되었다. 다양한 함수율 및 지름을 갖는 곰솔 원목의 열처리 소요시간을 예측하기 위하여 열처리 진행 중 처리목 내부의 온도분포를 유한차분법을 적용한 2차원 열전달 해석을 통하여 제시하였다. 열전달 해석을 위한 목재의 열적 특성은 함수율에 따른 열전도계수와 비열을 적용하였으며, 자연대류와 강제대류를 합한 형태의 혼합대류에 의한 혼합대류계수를 적용하였다. 실험값과 예측 값의 오차는 3 ~ 45%의 범위로 분석되었다. 곰솔 원목에서 초기함수율이 50%이고, 말구지름이 200 mm, 300 mm, 400 mm인 경우, 예측된 열처리 소요시간은 각각 10.9 h, 18.3 h, 27.0 h이었다. 초기함수율이 75%일 때, 지름에 따라 각각 13.6 h, 22.5 h, 32.8 h이고, 초기함수율이 100%일 때, 지름에 따라 각각 16.2 h, 26.5 h, 38.2 h이었다. 이러한 열처리 소요시간의 예측방법에 소나무와 잣나무 등 다른 소나무재선충병 피해목의 물리적 특성을 적용하면, 함수율과 말구지름에 따른 열처리 소요시간을 제시할 수 있을 것으로 판단된다.

수분-열처리에 따른 칡 전분의 물리화학적 성질 (Modification of Physicochemical Properties of Arrowroot Starch by Heat-Moisture Treatment)

  • 차환수;김관;김성곤
    • Applied Biological Chemistry
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    • 제27권4호
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    • pp.252-258
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    • 1984
  • 칡 전분의 수분을 18, 21 및 24%로 조절하고, $100^{\circ}C$에서 16시간 가열 처리한 다음, 물리화학적 성질을 규명하였다. X-ray회절 양상은 수분을 24%에서 열처리한 경우 C형에서 A형으로 전환되었고, 수분 처리 수준이 높아질수록 팽화력 및 용해도는 감소하였다. 수분(24%)-열처리한 시료는 동일팽화력에서 대조구보다 높은 용해도를 보였으며, 물 결합 능력은 수분처리 수준이 높을수록 현저히 증가하였다. 칡 전분은 가열 및 냉각에 대하여 안정된 paste 점도를 보였으며, 수분-열처리에 의하여 호화온도는 증가하였고 점도는 감소하였다.

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Thermal characteristics of spent activated carbon generated from air cleaning units in korean nuclear power plants

  • So, Ji-Yang;Cho, Hang-Rae
    • Nuclear Engineering and Technology
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    • 제49권4호
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    • pp.873-880
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    • 2017
  • To identify the feasibility of disposing of spent activated carbon as a clearance level waste, we performed characterization of radioactive pollution for spent activated carbon through radioisotope analysis; results showed that the C-14 concentrations of about half of the spent activated carbon samples taken from Korean NPPs exceeded the clearance level limit. In this situation, we selected thermal treatment technology to remove C-14 and analyzed the moisture content and thermal characteristics. The results of the moisture content analysis showed that the moisture content of the spent activated carbon is in the range of 1.2-23.9 wt% depending on the operation and storage conditions. The results of TGA indicated that most of the spent activated carbon lost weight in 3 temperature ranges. Through py-GC/MS analysis based on the result of TGA, we found that activated carbon loses weight rapidly with moisture desorption reaching to $100^{\circ}C$ and desorbs various organic and inorganic carbon compounds reaching to $200^{\circ}C$. The result of pyrolysis analysis showed that the experiment of C-14 desorption using thermal treatment technology requires at least 3 steps of heat treatment, including a heat treatment at high temperature over $850^{\circ}C$, in order to reduce the C-14 concentration below the clearance level.

Improving the Dimensional Stability of Spruce and Birch Boards by Heat-Treatment at 190 and $210^{\circ}C$

  • Kang, Ho-Yang
    • 한국가구학회지
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    • 제20권6호
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    • pp.560-565
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    • 2009
  • It is known that heat treatment decreases the hygroscopicity of wood. Thus heat-treated wood is good for outdoor construction due to its improved dimensional stability. This study is to investigate the hygroscopicity and discoloration of spruce and birch boards heat-treated above $190^{\circ}C$. The equilibrium moisture contents (EMCs) at all relative humidities decreased with the increase of heat treatment temperature and/or time for both spruce and birch. It was revealed that heat-treatment temperature affected more on the hygroscopicity thaan heat-treatment time. The average basic densities decreased for the spruce specimens, but increased for the birch specimens with an increase of the treatment time and/or temperature. The same heat treatment condition (190-8) made the birch specimens darker than the spruce specimens.

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A Study on the Wave Type and the Damage of Hair according to Water content when Heat permanent is treated - Focus on Damaged Hair -

  • Lee, Soon-Hee;Choi, Jung-Myung
    • 패션비즈니스
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    • 제12권6호
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    • pp.11-22
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    • 2008
  • The goal of this study is to provide beauticians with the fundamental material to use effectively heat permanent wave in beauty industry as well as their customer's satisfaction. It carried out an experiment with damaged hair of a woman in her late twenties to investigate the change of physical and morphological characteristics by its water content when performing heat permanent wave. After spreading 0g, 1g, 2g, 3g, and 4g of water on damaged hair respectively, heat permanent wave was treated and the change of hair was observed. The change of physical characteristic was compared through permanent wave form of hair, tensile strength and elongation. The change of morphological characteristic was observed through Scanning Electron Microscope(SEM) and Transmission Electron Microscope(TEM). The result of experiment on the physical specificity revealed that permanent wave form was the most ideal when the water content was 2g, also 3g. Though the materials with much moisture content formed the results were not satisfied. The material with 0g of water content didn't make the wave. In terms of tensile strength and elongation, tensile strength was generally reduced as per the damaged degree of hair. On the contrary, elongation was increased. It observed the changes of morphological characteristic that the damage on hair cuticle was deepen, as its moisture content was decreased, and cuticle's surface was worn away. The observation of fine structure on hair section by transmission electronic microscope also certainly showed the result that damaged hair having experience with chemical treatment had got much damaged to hair cuticle as well as hair cortex. Generally chemical treatment makes hair damaged. Under consideration of this aspect, the ultimate goal of this thesis is to minimize the damage of hair caused by chemical treatment and get the satisfaction on the hair style. According to the result of experiment, the damaged hair whose moisture content was 3g showed the best permanent wave form.

건조 및 초저온 처리에 의한 뽕나무 종자의 장기 보존 (Cryopreservation of Mulberry(Morus) Seeds in Liquid Nitrogen(L$N_2$))

  • 최영철;류근섭;방혜선
    • 한국잠사곤충학회지
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    • 제42권1호
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    • pp.1-5
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    • 2000
  • To investigate the possibility of crypreservation of mulberry seeds in liquid nitrogen(LN$_2$), characteristics of the seeds were examined after picking mulberry syncarps and drying-heat treatment. Storage in LN$_2$has the potential of providing indifinite preservation of valuable seed germplasm. Determining the tolerance of seeds among given cultivars to LN$_2$cooling and subsequent rewarming is the first step to establishing the feasibility of LN$_2$storage. Seeds of 4 mulberry varities were treated to LN$_2$(-196$\^{C}$) for 24 hours after drying heat treatment. Seed moisture content of Daeryukppong was the highest. As moisture content of mulberry seed was below 1%, storage in LN$_2$was safe. And drying heat treatment for 60 minutes was suitable to prevent decreased germination rate and germination vigor of seeds. The seeds of Cheongilppong were unsuibable to cryopreserve in LN$_2$for longterm storage.

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EPR의 열화에 의한 충.방전 전류 특성에 관한 연구 (A Study on Properties of Charge & Discharge Current by Degrade in EPR)

  • 이성일
    • 한국전기전자재료학회논문지
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    • 제21권7호
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    • pp.679-685
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    • 2008
  • This paper describes the degraded properties of between the charge and discharge current for ${\gamma}$-ray irradiated in electric power cable rubbers using in nuclear power generating station. The charge and discharge current of degradation in EPR(Ethylene Propylene Rubber), which were irradiated with the radiant capacity of 0.033 Mrad/h, have been measured in order to investigate the influence of the atmosphere(in amount of reinforcing agent, moisture absorption and heat treatment) on electrical properties. When ${\gamma}$-ray were irradiated on the EPR with more reinforcing agent from 4 to 40 Phr, charge and discharge currents was increase due to the amount of reinforcing agent. It was verified that the discharging and charging currents irradiated by ${\gamma}$-ray were higher than those that was not irradiated. The amount of the degraded current was more after moisture absorption than before moisture absorption. The charge and discharge current after heat treatment was similar to that of before heat treatment and it was decreased with the time elapsed. As these properties related with ${\gamma}$-ray irradiation dose, it is suggested that these properties can be utilized as a index of irradiation degradation.

Crystallinity change of silkworm variety cocoons by heat treatment

  • Bae, Yu Jeong;Noh, Si Kab;Um, In Chul
    • International Journal of Industrial Entomology and Biomaterials
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    • 제42권1호
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    • pp.7-13
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    • 2021
  • In the present study, the effect of heat treatment on the crystallinity of the outside of silkworm cocoon in nine different silkworm varieties was studied using ATR-FTIR spectroscopy. Additionally, the morphological structure and moisture regain of the cocoon were examined. The silkworm cocoon showed different colors and external features depending on the silkworm variety. Moreover, the thickness of the filament (15.3-27.6 ㎛) and moisture regain of the cocoon (9.0%-11.0%) were quite different depending on the silkworm variety. The crystallinity index of the cocoon outside varied from 52.1% to 56.1%, depending on the silkworm variety. J300 and MO42 showed the highest (56.1%) and the lowest (52.1%) crystallinity index, respectively, indicating that the microstructure of sericin of the outside of the cocoon was affected by the silkworm variety. Regardless of silkworm variety, their crystallinity indexes decreased from 52.1%-56.1% to 49.9%-43.6% depending on the silkworm variety by the heat treatment at 250 ℃. Interestingly, the crystallinity degree decrease was somewhat different depending on the silkworm variety, implying that the cocoon sericin microstructure is strongly influenced by the silkworm variety.

습열처리 변성 쌀을 이용한 식혜제조 (Application of Heat/Moisture-Treated Rices for Sikhe Preparation)

  • 육철;조석철
    • 한국식품과학회지
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    • 제28권6호
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    • pp.1119-1125
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    • 1996
  • 습열처리 방식으로 물리적 변성시킨 쌀을 이용하여 식혜당화 특성을 살펴 보았다. 쌀을 습열처리 하였을 때 쌀 전분의 팽윤이 억제되었고 온화온도는 상승하였으며 호화 엔탈피는 감소하는 등 쌀 전분의 특성이 변하였고 이렇게 처리한 쌀을 이용하여 식혜를 제조 하였을 때 식혜 당화 속도는 크게 향상되었다. 즉 $121^{\circ}C$, 15 psi에서 시간별로 autoclaving하여 습열처리를 한 쌀을 가지고 식혜를 제조한 결과 당화시간이 경과함에 따라 일반 쌀을 이용하여 당화하였을 때에 비하여 당화시간이 Brix 및 환원당을 기준하였을 때 약1/2로 단축되었다. 일반 쌀의 경우 당화시간이 2시간이 경과되었을 때 Brix가 8.2인데 비하여 $121^{\circ}C$에서 1시간 autoclaving한 쌀을 이용하여 당화하였을 경우 당화시간이 1시간만에 Brix가 8.7로 높아짐을 보여주었고 당화 중에 생성된 환원당 역시 Brix 측정결과와 비슷한 경향을 보여 주었다. 한편 HPLC로 분석한 당화액의 당 조성은 습열처리한 쌀로 당화한 것과 일반 쌀을 이용하여 제조한 당화액간에 큰 차이가 없었다.

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