• Food Science of Animal Resources
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• v.34 no.6
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• pp.777-783
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• 2014

This study investigated the effect of various freezing and thawing techniques on the quality of beef. Meat samples were frozen using natural convection freezing (NF), individual quick freezing (IQF), or cryogenic freezing (CF) techniques, followed by natural convection thawing (NCT) or running water thawing (RT). The meat was frozen until the core temperature reached $-12^{\circ}C$ and then stored at $-24^{\circ}C$, followed by thawing until the temperature reached $5^{\circ}C$. Quality parameters, such as the pH, water binding properties, CIE color, shear force, and microstructure of the beef were elucidated. Although the freezing and thawing combinations did not cause remarkable changes in the quality parameters, rapid freezing, in the order of CF, IQF, and NF, was found to minimize the quality deterioration. In the case of thawing methods, NCT was better than RT and the meat quality was influence on the thawing temperature rather than the thawing rate. Although the microstructure of the frozen beef exhibited an excessive loss of integrity after the freezing and thawing, it did not cause any remarkable change in the beef quality. Taken together, these results demonstrate that CF and NCT form the best combination for beef processing; however, IQF and NCT may have practical applications in the frozen food industry.

• Asian Journal of Turfgrass Science
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• v.4 no.1
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• pp.42-48
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• 1990

Experiments were conducted to investigate the soil freezing depth and pattern with freezing measuring instruments during 1988-l989 winter season in Kangwon province. Freezing measuring instrument was made with acrylic pipes which were consisted of inner and outer parts. Inner pipe was filled with 0.01 % methylene blue solution and rubber hose to protect pipe breakdown by solution freezing. Freezing measurements were carried out by observing discoloration of methylene blue solution. Moisture content of evergreen trees and ground cover plants was also examined in the winter season. The observed results are as follows: 1.In the land of I OOM above sea level, soil freezing depth became deeper as the sum of Accumulated degree-days of temperature below 0˚C(0˚C . day) increased: Soil freezing depth was 30-40cm at l00˚C, 42-43cm at 150˚C, and 47cm at 200˚C day 2.Soil freezing with vinyl mulching was less developed by l3cm at l00˚C with sum of subzero temperature, by l7cm at 200˚C than that of the bare ground. Soil of rich hulls mulching with 4Ocm was not frozen until soil freezing at the bare ground was developed to 25cm depth. 3.Cashmeron mulching was more effective than felt mulching in the heat insulation of soil. 4.Thawing of soil was done from the lowest part of the frozen in the ground to upward in the beginning and after that it was done from the surface of frozen soil to downward. Finally thawing was completed at the middle of frozen soil.

• 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.

• Journal of the Korean Geosynthetics Society
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• v.12 no.3
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• pp.23-29
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• 2013

The mechanical behavior of frozen soils is different from that of unfrozen soils due to the phase change between water and ice. The strength characteristics of frozen soils are governed by the intrinsic material properties such as grain size, ice and water content, air bubbles, and by externally imposed testing conditions such as temperature, freezing time, and strain rate. Especially, the strength of the frozen soils is generally higher than that of unfrozen soils due to ice binding capacity with soil particles, and is strongly affected by a highly complex interaction between the solid soil skeleton and the pore matrix, composed of ice and unfrozen water. In this study, the direct shear test and unconfined compression test are carried out inside of a large-scaled freezing chamber, and the relationships between cohesion and unconfined compression strength under various freezing temperature conditions are discussed.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.233-238
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• 1996

This study was conducted to investigate the effects of cryoprotective agents and thawing temperature on the survival rate of the bisected embryos of mouse. The results of this study were summairzed as follows: 1. In in vitro culture after frozen with DMSO, glycerol, ethylene glycol or propanediol and thawed, the rates of normally developed bisected morula which was denuded were 31.7, 39.1, 28.0 and 23.1%, respectively. 2. The survival rates of bisected morula encased into the zona pellucida in in vitro culture after frozen with DMSO, glycerol, ethylene glycol or propanediol and thawed were 72.4, 68.7, 64.0 and 59.5%, respectively. 3. The survival rates of bisected denuded blastura in in vitro culture after frozen with DMSO, glycerol, ethylene glycol or propanediol and thawed were 48.3, 44.8, 32.1 and 28.6%, respectively. 4. The survival rates of bisected blasturae encased into the zona pellucida in in vitro culture after frozen with DMSO, glycerol, ethylene glycol or propanediol and thawed were 73.6, 67.4, 53.0 and 49.1%, respectively. 5. In in vitro culture after frozen with DMSO, glycerol, ethylene glycol or propanediol and thawed at room temperature, the rates of the normally developed bisected morula which was encased into the zona pellucida were 67.1, 62.3, 57.7 and 53.0%, respectively, and those of the bisected blasturae encased into the zona pellucida were 70.8, 65.4, 56.6 and 52.1%, respectively. 6. The survival rates of bisected morula which was encased into the zona pellucida in in vitro culture after forzen with DMSO, glycerol, ethylene glycerol or propanediol and thawed at 37$^{\circ}C$ were 74.3, 71.3, 63.9 and 57.4%, respectively, and those of bisected blastura encased into zona pellucida were 76.0, 69.1, 61.1 and 56.1%, respectively.

• Animal Bioscience
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• v.35 no.8
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• pp.1270-1278
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• 2022

Objective: The objective of this study was to evaluate quality characteristics of reduced-salt pork sausage (PS) using pre-rigor muscle compared to those of regular-salt PS. In addition, effects of freezing on sausage batter with different temperatures (-30℃ vs -70℃) on quality characteristics of both sausage batter and cooked sausages during frozen storage were observed. Methods: Pre-rigor and post-rigor pork hams were used to manufacture low-fat sausages. Sausages using post-rigor (Post) muscle were manufactured at a salt level of 1.5%, whereas those with pre-rigor (Pre) muscle were processed at salt level of 1.0%. After these muscles were made at two salt levels (1.5% salt, Post-rigor; 1.0% salt, Pre-rigor), Sausage batters were stored at two frozen temperatures (-30℃ vs -70℃). During storage for 12 wks, they were measured for physicochemical and textural properties every 4 wks up to 12 wks. Results: pH values and temperatures of sausage batter of pre-rigor muscle were higher than those of post-rigor muscle regardless of the frozen temperature. The lightness and yellowness values of batter at the initial storage were the highest during storage. For PS, there were no differences in most parameters measured among all treatments. However, expressible moisture values (%) of Pre-30 and Pre-70 were lower than those of Post-30 (p<0.05). Conclusion: Regardless of frozen temperature during storage, quality characteristics of pre-rigor PS with salt level of 1.0% salt were similar to those of post-rigor PS with salt level of 1.5%. By using the pre-rigor muscle, salt content could be reduced by one third of the regular-salt level (1.5%) of post-rigor muscle.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.691-696
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• 2012

We conducted this study to investigate the quality characteristics of mashed red pepper(MRP) with different freezing(-20, -30, -40, -50, -60 or $-70^{\circ}C$) and thawing(4, 10, 20, 30, 40 or $50^{\circ}C$) temperature. Frozen and thawed MRP was evaluated for ascorbic acid contents(AsA), capsaicinoids contents, free sugar contents, ASTA value, and flavor patterns. The AsA of frozen MRP with freezing temperature showed a range of 67.08~80.35 mg/100 g FW, and the mean AsA losses after frozen were 57~64% compared to raw red pepper. Capsaicinoids contents, free sugar contents, and ASTA values of frozen MRP with freezing temperature were no significant difference compared to raw red pepper. The AsA of thawed MRP with thawing temperature showed a range of 70.34~81.59 mg/100 g FW, and the mean AsA losses after thawed were 45.12~52.69% compared to raw red pepper. Capsaicinoids contents and free sugar contents of thawed MRP with thawing temperature were no significant difference compared to raw red pepper, whereas the ASTA value decreased according to the increasing of thawing temperature. Flavor patterns of thawed MRP after $20{\sim}50^{\circ}C$ thawing were clearly different from the raw red pepper. Overall, it is recommended that the best freezing and thawing temperature for preserving the quality of MRP is freezing at $-20^{\circ}C$ and thawing at $10^{\circ}C$.

• Journal of the Korean Geotechnical Society
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• v.33 no.3
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• pp.37-47
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• 2017

The geotechnical characteristics of frozen ground is one of the key design issues for the construction of infrastructure in cold region. In this study, the dynamic properties (shear modulus and damping ratio) of frozen and unfrozen soils sampled from Terra Nova Bay located in eastern Antarctica, where Jang Bogo station was built, were investigated using Stokoe-type resonant column test (RC). In order to freeze the reconstituted soil specimen, the RC testing equipment was modified by adding a cooling system. A series of resonant column tests were performed in frozen and unfrozen soils with various soil densities and temperatures. The shear modulus (G) and damping ratio (D) of soil frozen at $-7^{\circ}C$ were compared with those of unfrozen soil. In addition, the effect of temperature rise on the maximum shear modulus ($G_{max}$) and damping ratio was experimentally investigated. This study has significance in that the difference of dynamic soil properties between frozen and unfrozen soils and the effect of temperature rise on frozen soil were identified.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.910-915
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• 1996

Ascidian muscle was blackened during the frozen storage, so the prevention against blackening was investigated. Low storage temperature and packaging in polyethylene bags delayed the blackening of ascidian muscle during the frozen storage. The blackening was prevented by dipping for $3{\sim}5$ minutes in 3% brine solution containing 0.3% citric acid, packaging in the polyethylene bag, freezing at $-45^{\circ}C$ for 5 hours and storing at $-20^{\circ}C$. Under this condition, the color and the quality of frozen ascidian muscle were nearly not changed for 200 days.

• Korean Journal of Animal Reproduction
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• v.8 no.1
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• pp.22-28
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• 1984

This experiment was carried out to investigate effects of DMSO or ethylene glycol as a cryopotectant and of freezing methods on survival rate of forozen-thawed rat 2-cell embryos by morphological observation. 2-cell embryos were recovered from oviducts of Sprague Dawley females mated with males of same strain on day 2 of pregnancy after inducing superovulation by intrapertioneal injection of PMSG and HCG. In slow freezing and thawing groups, embryos were frozen to -79$^{\circ}C$ or -196$^{\circ}C$ in a glass test tube containing 0.2ml PBI with 1.5M DMSO or 1.2M ethylene glycol at a rate of 0.3-1.0C/min. and thawed slowly. When samples were frozen to -79$^{\circ}C$, higher survival rate was obtained in the medium containing DMSO (43.9%) than ethylene glycol (41%). And similar result was obtained (32.5% in DMSO vs. 31.4% in ethylene glycol) when samples were frozen. In rapid freezing and thawing groups, embryos were frozen to -79 or -196$^{\circ}C$ in a glass test tube containing 0.2ml of PBI with 1.5M DMSO or 1.2M ethylene glycol by rapid cooling, and thawed rapidly. When samples were frozen to -79$^{\circ}C$, 1.5M DMSO (13.2%) was more effective than 1.2M ethylene glycol (6.1%). When the storage temperature was -196$^{\circ}C$, survival rates were 9.8% in 1.5M and 5.4% in 1.2M ethylene glycol.