• Food Science of Animal Resources
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• v.29 no.4
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• pp.457-465
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• 2009

The characteristics of Holstein colostrum according to the methods that were employed in processing it were analyzed in this study to improve its industrial utilization. Colostrum samples were collected from the dairy farm of the National Institute of Animal Science (NIAS). The milk fat, protein, lactose, and SNF contents of colostrum were 4.34, 6.99, 3.37, and 11.10%, respectively. The effects of spray drying, freeze drying, freezing, acidification, and inoculation of lactic-acid bacteria on the characteristics of colostrum were then compared. The freezing of colostrum was found to be proper for long-term storage in a farm. Freeze-dried colostrum powder could not meet the processing requirements and the component standards for animal products in terms of the total bacterial and coliform bacteria counts, but spray-dried colostrum powder could meet the microbiological requirements because of its bactericidal effect during the spray-dry treatment. The inoculation of lactic-acid bacteria showed a better inhibitory effect on coliform than the acidification treatment, but protein precipitation appeared because of the low pH and the high acidity. To estimate the effects of the processing methods employed on the IgG of colostrum, the IgG contents of the milk treated by long temperature long time (LTLT) ($65^{\circ}C$, 30 min), by inoculating the lactic acid bacteria starter, by spray drying, and by freeze drying were measured. The IgG contents of the colostrum were changed significantly by the processing treatment employed, from 53.98 mg/mLto 33.28, 34.82, 21.98, and 36.89 mg/mL, respectively.

• Food Science and Preservation
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• v.18 no.5
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• pp.661-668
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• 2011

This study was conducted to devise appropriate blanching-process conditions as a means to convert Doraji, which is widely used in Korean food due to its unique fragrance and flavor, into frozen food materials for various uses. For the Hunter L values representing the brightness transformation among the surface color and gloss changes that were observed in Doraji before and after freezing, and after Doraji went through a blanching process, the specimen that went through a blanching process at $80^{\circ}C$ showed a significantly higher value compared to another specimen processed at a higher temperature, and the first specimen's value also rose after freezing. Meanwhile, for the hardness values, they declined more as the blanching temperature became higher and as the processing time became longer. For the number of total counts and the number of coliform groups, the number of total counts at $3.75{\times}10^5$ and $1.25{\times}10^5$ cfu/g before the blanching process was reduced into the approximately 2-3 log scale, and no coliform group was detected after the blanching process. As for the peroxidase activity, its activation was decreased by the blanching process, and more than 89% of the peroxidase became inactivated in all the specimens that went through the blanching process. The sensory characteristics of the frozen-thawed Doraji by test group showed the radish leaves blanched at $90^{\circ}C$ for 1 min to be the most highly evaluated in terms of the overall preference level (p<0.05).

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1691-1707
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• 2022

Cheonji Lake, the caldera of Baekdu Mountain, located on the border of the Korean Peninsula and China, alternates between melting and freezing seasonally. There is a magma chamber beneath Cheonji, and variations in the magma chamber cause volcanic antecedents such as changes in the temperature and water pressure of hot spring water. Consequently, there is an abnormal region in Cheonji where ice melts quicker than in other areas, freezes late even during the freezing period, and has a high-temperature water surface. The abnormal area is a discharge region for hot spring water, and its ice gradient may be used to monitor volcanic activity. However, due to geographical, political and spatial issues, periodic observation of abnormal regions of Cheonji is limited. In this study, the degree of ice change in the optimal region was quantified using a Landsat -5/-7/-8 optical satellite image and a Modified U-Net regression model. From January 22, 1985 to December 8, 2020, the Visible and Near Infrared (VNIR) band of 83 Landsat images including anomalous regions was utilized. Using the relative spectral reflectance of water and ice in the VNIR band, unique data were generated for quantitative ice variability monitoring. To preserve as much information as possible from the visible and near-infrared bands, ice gradient was noticed by applying it to U-Net with two encoders, achieving good prediction accuracy with a Root Mean Square Error (RMSE) of 140 and a correlation value of 0.9968. Since the ice change value can be seen with high precision from Landsat images using Modified U-Net in the future may be utilized as one of the methods to monitor Baekdu Mountain's volcanic activity, and a more specific volcano monitoring system can be built.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1750-1756
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• 2011

This study evaluated the effect of antioxidants treatment; (Vit. C and E) on the physicochemical and sensory properties of Tarakjuk treated with gamma-irradiation under two different temperature conditions, e.g. room and frozen temperatures. In samples of Tarakjuk irradiated at room temperature, Vit. C gradually decreased the pH level as the concentration increased (p<0.05), whereas Vit. E did not. Addition of both Vit. C and E to Tarakjuk decreased TBA (2-thiobarbituric acid) value while also increasing viscosity. However, these antioxidants did not cause any change in Hunter's color values. Sensory properties showed that Vit. C and E significantly improved the overall acceptability of Tarakjuk, and the addition of 0.1% each Vit. C and E was best treatment. In samples of Tarakjuk subjected to combined treatment with antioxidants and irradiation under frozen temperature conditions, Vit. C and E were effective in decreasing TBA value, improving viscosity, and maintaining sensory quality. Especially, co-treatment with 0.1% Vit. C and E augmented the observed effect (p<0.05). Therefore, combined treatment with antioxidants and irradiation under frozen temperature conditions could improve the final sensory quality of gamma-irradiated Tarakjuk.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.1
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• pp.27-31
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• 1985

To get well matured farm yard manure from ricestraw as quickly as possible during winter season, straw piles wrapped with polyethylene film and/or straw thatch were stored in the vinyl house or open air. Their maturities and changes of temperature in heap were investigated from the beginning of December 1983 to March of next year. Heat increment in vinyl house was high $2-5^{\circ}C$ than at open air at the lowest temperature but it didn't rise over the freezing point. However, the highest temperature was arisen over than $20^{\circ}C$ averagely at the vinylhouse compared to those of open air during three months. Temperature in piles of straw manure was reached to about $70^{\circ}C$ in maximum and rose again very rapidly after repiling in the vinyl house, whereas increment of temperature after repiling was delayed and took long times to reach the maximum temperature at open air. Wrapping with P.E. film also affected the insulation of decomposing heat of straw pile and promoted the repeat of piling even at open air. By these results, ricestraw would be decomposed rapidly by insulation with P.E. film in the vinyl house and could be reached to matured compost for application to field on next spring season. P.E. film covered for vinyl house was endured until May of next year without tear by weathering.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.5
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• pp.66-77
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• 2019

This study investigated the feasibility of wintering evergreen broad-leaf trees in the Incheon coastal area through a climate analysis. The coldest monthly mean air temperature ranged from $-2.9^{\circ}C{\sim}-1.6^{\circ}C$. The warmth index of the coastal area of Incheon ranged from $98.89^{\circ}C{\cdot}month-109.03^{\circ}C{\cdot}month$, while the minimum air temperature year ranged from $-13.9^{\circ}C{\sim}-3.6^{\circ}C$. This proved that the Incheon coastal area was not suitable for evergreen broad-leaf trees to grow as the warmth index ranges from $101.0^{\circ}C{\cdot}month{\sim}117.0^{\circ}C{\cdot}month$, and the temperature year-round is $-9.2^{\circ}C$ or higher. This suggests the coastal areas of Incheon is not suitable for the growth of evergreen broad-leaf trees, however some evergreen broad-leaf trees lived in some parts of the area. Wind speed reduction and temperature effect simulations were done using Landschaftsanalyse mit GIS program. As a result of the simulations of wind speed reduction and temperature effects affecting the evergreen broad-leaf trees, it was discovered that a coastal wind velocity of 8.6m/sec was alleviated to be 5m/sec~7m/sec when the wind reached the areas where evergreen broad-leaf trees were present. It was also discovered that species that grew in contact with buildings benefited from a temperature increase of $1.1^{\circ}C{\sim}3.4^{\circ}C$ due to the radiant heat released by the building. Simulation results show that the weather factors affecting the winter growth damages of evergreen broad-leaved trees were wind speed reduction and local warming due to buildings. The wind speed reduction by shielding and local warming effects by buildings have enabled the wintering of evergreen broad-leaved trees. Also, evergreen broad-leaved trees growing in the coastal area of Incheon could be judged to be gradually adapting to low temperatures in winter. This study reached the conclusion that the blockage of wind, and the proximity of buildings, are required for successfully wintering evergreen broad-leaf trees in the coastal area of Incheon.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.893-901
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• 2015

This study investigated the effects of thawing conditions on physiological activities and quality of peeled garlic. Peeled frozen garlic was analyzed after thawing at low temperature ($4^{\circ}C$), room temperature ($20^{\circ}C$), tap water ($20^{\circ}C$), radio frequency of 27.12 MHz, and 2.45 GHz in a microwave. As a result, the time required to thaw garlic to $0^{\circ}C$ by various thawing methods was shortest at2.45 GHz in a microwave, followed by $20^{\circ}C$ tap water, radio frequency of 27.12 MHz, $20^{\circ}C$, and $4^{\circ}C$. Microwave thawing was faster than other methods, but it resulted in significant non-uniformity of heating. The hardness of peeled garlic significantly decreased upon freeze-thawing, whereas it showed improved hardness upon radio-frequency thawing. Total color difference in garlic increased upon freeze-thawing, and it was not improved by various thawing methods. Antioxidant activities were determined for DPPH radical scavenging ability, SOD-like activity, and reducing power. Total phenolic compounds and flavonoids in garlic extract were measured as $3.222{\pm}0.214{\mu}g$ GAE/g and $0.149{\pm}0.03{\mu}g$ QE/g, respectively. The content of total phenolic compounds was significantly reduced by 2.45 GHz microwave thawing ($1.90{\pm}0.02{\mu}g$ GAE/g); however, flavonoid contents were slightly reduced under freezing and thawing conditions. The DPPH radical scavenging ability of garlic extracts was not affected by thawing methods; however, SOD-like activity and reducing power were slightly reduced by freeze-thawing. These results indicate that physiological activities were not improved by radio-frequency thawing; however, thawing time and maintain hardness were reduced compared with conventional thawing methods.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.267-276
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• 2006

To investigate the physiological responses to winter freezing stress naturally occurring, the level of lipid peroxidation and enzymatic antioxidant responses were compared between zoysiagrass and creeping bentgrass during overwintering. Root mortality of creeping bentgrass was significantly higher than zoysiagrass at January. Root growth of creeping bentgrass was nearly parallel with temperature fluctuation, while zoysiagrass showed little changes in root growth until the end of April. Total nonstructural carbohydrate of zoysiauass was 10% higher than creeping bentgrass. Malondialdehyde(MDA) content in creeping bentgrass was 2-fold higher than that of zoysiagrass. The peroxidase(POD) activity of creeping bentgrass in January was 4.2 times higher, while superoxide(SOD) and catalase(CAT) activities lowered 22% and 67%, respectively, compared to zoysiagrass. These results suggest that zoysiagrass roots much properly operate cold tolerance mechanism and: are less susceptible to cold stress in comparison to creeping bentgrass.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.770-774
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• 2002

The effect of mixing ratio of materials and their retort processing conditions on the physical properties and preference of oyster porridge were investigated. Rice gave adequate viscosity (about 800 cp) to the porridge as it was used 10～12% level and half of it was ground. Potato starch, waxy corn starch, and Perfectamyl AC showed small variation in viscosity unrelated to the temperature, that was a good condition for high quality porridge. Especially, waxy corn starch had a good property for retort porridge because its viscosity was maintained high during the processing and decreased to preferable one after processing. Purity CSC, modified starch gave gum-like texture and didn't cause water-separation much after freezing and thawing treatment of the porridge. Therefore, it was good for enhancing the physical property of the porridge as a co-additive of waxy corn starch when it was used at quarter level of waxy corn starch. Xanthan gum increased dispersibility of materials and it was useful for stabilizing physical quality of the porridge without affecting preference when it was used below 0.2% concentration. As a result, the optimal material-mixing ratio was determined as rice 10% (50% of it was ground), waxy corn starch 1.5%, Purity CSC 0.5%, xmthan gum 0.2%, salt 0.3%, and water 87.5%. Oyster's porridge, retort processed with this recipe, showed stable physical property after 6 month storage at room temperature.

• Journal of Mushroom
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• v.15 no.2
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• pp.69-72
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• 2017

Diversification to develop oak pruned neck utilization technology reduction of operation cost of cheonma(Gastrodia elata) farmers is the purpose of this research, but the results of the experiment are as follows. The soil chemistry of the plantation was very weak in 2015 when the pH was 5.7, weakly acidic and EC was 0.41 (ds/m), but the faux spring area was very sunny, but at the end of May, early June, late July And so on were at a maximum temperature of $25^{\circ}C$ or more, and underground temperature fell below freezing in late January 2016. In the content of the survey of the harvested volume, treatment with a diameter of 6 to 10 cm appeared in 1,366 g total weight and in treated plots with a diameter of 20 cm or more, appeared in 1,542 g, confirming that the number and weight of the interspaces from the small neck is higher than the practice.