• Title/Summary/Keyword: Deep freezing

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Effects of Deep Freezing Temperature for Long-term Storage on Quality Characteristics and Freshness of Lamb Meat

  • Choi, Mi-Jung;Abduzukhurov, Tolibovich;Park, Dong Hyeon;Kim, Eun Jeong;Hong, Geun-Pyo
    • Food Science of Animal Resources
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    • v.38 no.5
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    • pp.959-969
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    • 2018
  • This study investigated the effects of deep freezing and storage temperature ($-50^{\circ}C$, $-60^{\circ}C$, and $-80^{\circ}C$) on the quality and freshness of lamb. To compare the qualities of deep frozen and stored lamb, fresh control and normal freezing conditions ($-18^{\circ}C$) were adopted. As quality and freshness parameters, drip loss (thawing loss and cooking loss), water-holding capacity (WHC), texture profile analysis (TPA), thiobarbituric acid reactive substances (TBARS), and total volatile basic nitrogen (TVBN) were evaluated during 5 months of storage. Temperature influenced the drip loss and WHC, and deep freezing minimized the moisture loss during frozen storage compared to the normal freezing condition. Lamb frozen and stored at deep freezing temperature showed better tenderness than that stored in normal freezing conditions. In particular, lamb frozen at lower than $-60^{\circ}C$ exhibited fresh lamb-like tenderness. Regardless of temperature, evidence of lipid oxidation was not found in any frozen lamb after 5 months, while TVBN was dependent on the applied temperature. Therefore, this study demonstrated that deep freezing could potentially be used to maintain freshness of lamb for 5 months. From the quality and economic aspects, the freezing and storage condition of $-60^{\circ}C$ is estimated as the optimum condition for frozen lamb.

Seismic deformation behaviors of the soft clay after freezing-thawing

  • Zhen-Dong Cui;Meng-Hui Huang;Chen-Yu Hou;Li Yuan
    • Geomechanics and Engineering
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    • v.34 no.3
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    • pp.303-316
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    • 2023
  • With the development and utilization of urban underground space, the artificial ground freezing technology has been widely used in the construction of underground engineering in soft soil areas. The mechanical properties of soft clay changed greatly after freezing and thawing, which affected the seismic performance of underground structures. In this paper, a series of triaxial tests were carried out to study the dynamic response of the freezing-thawing clay under the seismic load considering different dynamic stress amplitudes and different confining pressures. The reduction factor of dynamic shear stress was determined to correct the amplitude of the seismic load. The deformation development mode, the stress-strain relationship and the energy dissipation behavior of the soft clay under the seismic load were analyzed. An empirical model for predicting accumulative plastic strain was proposed and validated considering the loading times, the confining pressures and the dynamic stress amplitudes. The relevant research results can provide a theoretical reference to the seismic design of underground structures in soft clay areas.

Physicochemical Properties of Pork Neck and Chicken Leg Meat under Various Freezing Temperatures in a Deep Freezer

  • Kim, Eun Jeong;Lee, SangYoon;Park, Dong Hyeon;Kim, Honggyun;Choi, Mi-Jung
    • Food Science of Animal Resources
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    • v.40 no.3
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    • pp.444-460
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    • 2020
  • This study was conducted to investigate the effects of freezing and storage temperature (-18℃, -50℃, and -60℃) on the physicochemical properties of pork neck and chicken leg meat in home-scale deep freezers. Pork neck was cut into a thickness of 3 cm (9×9×3 cm, 150 g), individually packed in air-containing packages, and stored at different temperature (-18℃, -50℃, and -60℃) for 6 months. Chicken leg meats were prepared (10 cm long, weighing 70 g) and packed in the same manner. Frozen samples were thawed at 2℃. Physicochemical properties such as thawing loss, cooking loss, water-holding capacity, color, volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances (TBARS) were evaluated. The samples frozen by deep freezing (-60℃) was favorable with respect to thawing loss, color, and VBN. Samples frozen at -60℃ had lower values of thawing loss and VBN than those frozen at -18℃ for all storage periods (p<0.05). Color parameters were more similar to those of fresh meat than to those of samples frozen at -18℃ for 6 months. The TBARS of all samples were below 0.3 mg malondialdehyde/kg, thereby indicating oxidative stability of lipids. Consequently, deep freezing at -60℃ may be acceptable for maintaining the quality of fresh pork neck and chicken leg meat for 6 months without deterioration.

Dyeing Properties and Storage Stability of Leaf Powder Prepared from Dyer's Knotweed (I) - by Freeze Drying method - (생쪽잎분말의 염색성 및 저장성 (I) - 동결건조방법 -)

  • Shin, Youn-Sook;Son, Kyung-Hee;Yoo, Dong-Il
    • Textile Coloration and Finishing
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    • v.21 no.1
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    • pp.10-20
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    • 2009
  • The objective of this study is to investigate the efficacy of leaf powder colorants as substitutes for traditional fresh juice extract dyeing. Three kinds of leaf powder colorants were prepared by freeze drying method with or without deep freezing as pre-treatment: one powder colorant from fresh leaf juice with deep freezing; two kinds of powder colorant from fresh leaves with and without deep freezing. Their dyeing properties and storage stabilities were studied and compared with the traditional fresh juice extract dyeing. The presence of indigo in the powder colorants was confirmed by UV/Visible absorption spectra. They showed absorption peak at 602nm which was same with indigo absorption peak. Dyeing was done at low temperature around 6$^{\circ}C$. All three powder colorants produced B colors on silk fabrics, showing similar color to the one dyed traditionally with fresh juice extract. The powder colorants from leaves gave higher color strength than the powder from leaf juice. The powder colorant prepared from leaves with deep freezing was the most stable for long term storage as its color and color strength were not changed after 360 days. So, this was used for further dyeing to study the effects of concentration and repeat dyeing on color strength and colorfastness. Fastnesses to dry cleaning and rubbing were fairly good above 4 rating. Further study is needed to improve light fastness. It was concluded that the leaf powder colorant with deep freezing could be used as a substitute for traditional juice extract dyeing at all seasons.

Frost Heaving in Artificial Ground Freezing

  • 생뢰효박
    • Proceedings of the Korean Geotechical Society Conference
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    • 1994.03b
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    • pp.13-46
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    • 1994
  • Artificial ground freezing methods have been applied to geotechnical construction projects for stabilizing earth materials and controlling water seepage into the ground. However, this can result in frost heaving and causes the same engineering problems as encountered with the natural freezing of soil. In natural freezing, the ground freezes from the surface downward. When artificial ground freezing is applied at a deep location, however, freezing is limited locally. The soil condition differs between them as follows: Natural freezing - unsaturated and without overburden pressure. Artificial freezing -- saturated and under overburden pressure. The authors investigated the practical application of artificial ground freezing and examined the frost behaviour of a saturated soil under overburden pressure. This paper presents the results obtained from experiments concerning frost heaving and discusses frost heaving at the freezing site.

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Preservation of Marine Heterotrophic Bacteria by Using a Deep-freezing Method

  • Park, Shin-Hye;Lee, Hyun-Sang;Lee, Hong-Kum
    • Journal of Microbiology
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    • v.39 no.3
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    • pp.240-243
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    • 2001
  • The effect of cryoprotectants and suspending solutions on the preservation of marine heterotophic bacteria was investigated. Six halotolerant and four halophilic bacterial isolates suspended in either distilled water or artificial seawater were preserved in glycerol and dimethylsulfoxide at -70$\^{C}$, respectively. After one year of preservation, the recovery rates on the appropriate agar plates were estimated. The survival rate was found to be dependent on the strain tested, regardless of the preservation conditions tested.

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Deep Brain Stimulation of the Subthalamic and Pedunculopontine Nucleus in a Patient with Parkinson's Disease

  • Liu, Huan-Guang;Zhang, Kai;Yang, An-Chao;Zhang, Jian-Guo
    • Journal of Korean Neurosurgical Society
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    • v.57 no.4
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    • pp.303-306
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    • 2015
  • Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is a novel therapy developed to treat Parkinson's disease. We report a patient who underwent bilateral DBS of the PPN and subthalamic nucleus (STN). He suffered from freezing of gait (FOG), bradykinesia, rigidity and mild tremors. The patient underwent bilateral DBS of the PPN and STN. We compared the benefits of PPN-DBS and STN-DBS using motor and gait subscores. The PPN-DBS provided modest improvements in the gait disorder and freezing episodes, while the STN-DBS failed to improve the dominant problems. This special case suggests that PPN-DBS may have a unique role in ameliorating the locomotor symptoms and has the potential to provide improvement in FOG.

Fine Structure of Pericanalicular Cytoplasm of Taurocholic Acid-treated Rat Liver as Revealed by Deep Etching with Rapid Freezing (Taurocholic acid 투여 흰쥐 담세관주위세포질의 미세구조에 관한 급속동결 deep etching법에 의한 연구)

  • Shin, Young-Chul
    • Applied Microscopy
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    • v.28 no.1
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    • pp.73-82
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    • 1998
  • To elucidate how microfilaments and vesicles participate in bile formation, the pericanalicular cytoplasms were observed in the liver of rats treated with taurocholic acid by deep etching with rapid freezing, and copmpared them with the findings on convensional thin sections. The microfilaments were identified around the bile canaliculi in the forms of core filaments of microvilli, filaments of pericanalicular web running in parallel to the border of bile canaliculi, and filaments on the junctional complex. In taurocholic acid-treated rats, microfilaments could be visualized around the bile canaliculi and along their borders. The microfilaments appeared to be installed to link to both the canalicular membrane and vesicles. Such specialized microfilaments are considered to participate in the translocation of vesicles in the pericanalicular cytoplasm. From the evidence, it is assumed that the microfilament induces the vesicles to transport and fuse to bile canalicull into which bile acids is secreted by exocytosis.

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Color Characteristics of Soybeans as Influenced by Freezing and Cooking Conditions

  • Lee, Jun-Ho;Seog, Eun-Ju;Park, Yong-Hee
    • Preventive Nutrition and Food Science
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    • v.3 no.2
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    • pp.105-110
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    • 1998
  • Color characteristic of thawed samples of frozen cooked soybean pree of selected cultivar (Gomultong) depending upon cooking temperature an dtime as well as freezing conditions were evaluated . Samples were either cooled in 4$^{\circ}C$ refrigerator (control), or frozen at - 4$0^{\circ}C$ deep freezer for 12 hrs and then stored in 4 $^{\circ}C$ refrigerator , or immersed in liquid nitrogen (LN2) and then each samples were cooked for 5, 10, 20 and 40 min at 65, 80 and 95$^{\circ}C$, respectively. Freezing effect was not significant for all color characteristics except for b. Significant cooking temperature by cooking time interacts were found for all characteristics excepts for L.

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Effect of Temperature and Stirring speed on the Processing of Plum Concentrated Extract. (온도 및 교반속도가 매실엑기스 가공에 미치는 영향)

  • 이상대;조숙현
    • Food Science and Preservation
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    • v.3 no.2
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    • pp.121-129
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    • 1996
  • Plum highlighted as a health food is needed to diversify the processed products because labor storage is big problem since the fruit was producted massively in June. The Plum was extracted by the pressing type extractor after washing, drying and removing the seed by seed separator. The crude extract was concentrated with stainless steel vessel at different temperature and stirring speed. This study was obtained as follows. The sugar content of fresh plum concentrated extract was 55.3~58.3$^{\circ}$Brix, and of the freezing plum concentrated extract was 75.5~70.3$^{\circ}$Brix. In color difference, the freezing plum concentrated extract was more deep black than fresh plum. In change patten of pH, it was decreased as concentration was proceed. The final pH was 2.3~2.2 in fresh plum, and 1.8~2.2 in freezing plum. The total acid content of fresh plum concentrated extract and the freezing plum was 45.4~47.8, 60.3~60.9%, respectively. The content of evaporation at 85$\pm$5$^{\circ}C$ was constant irrespective of stirring speed. The yield of extraction of fresh plum was higher than freezing plum. According to this results, the use of stainless vessel, 50rpm, which gave a highly qualified plum concentrated extract.

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