• Journal of Sericultural and Entomological Science
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• v.52 no.1
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• pp.73-78
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• 2014

This study was carried out to establish the self-specification and shelf-life by standardization of manufacturing process for Tenebrio molitor larvae. First, standardization of manufacturing process for T. molitor was set up. Sterilization for larvae placed on a multistage shelf with intervals of about 10 cm was carried out at $115^{\circ}C$, $1kgf/cm^2$ for 10 min. After sterilization, T. molitor larvae were frozen at less than $-35^{\circ}C$ for more than 12 hrs. And then, they were dried under $-15^{\circ}C$, 0.5 torr vacuum for more than 30 hrs. Second, we decided self-specification for T. molitor larvae. Their moisture, acidity, peroxide, crude protein and crude fat level should be 5% or less, 3 mg/g or less, 30 meq/g or less, 45% or more, and 25% or more, respectively. Also, oleic acid, representative material, level was set up 11 ~ 16%. Third, we decided shelf-life by analysis of the physicochemical characteristic, sensory evaluation and microbial indicators. The final expiry date for lyophilized T. molitor larvae in PET bottle was calculated as 12 months from date of manufacture. We expect that optimal manufacturing process system, self-specification, and shelf-life proposed in this study can be used in industrial production of T. molitor as a novel food.

• Food Science and Preservation
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• v.23 no.3
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• pp.438-444
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• 2016

This study was performed to determine the optimal freezing point for the reliable cold storage of Korean agricultural products, and to provide basic data for determining the storage temperature based on the quality characteristics. Additional supercooling temperature analysis was conducted to explore the possibility of supercooling storage. To determine the effects of quality characteristics on the freezing point, the hardness, acidity, moisture and sugar content were analyzed. The crops were frozen using customized cooling unit and their freezing and supercooling points were determined based on their heat release points. The freezing temperatures of garlic, leek, cucumber, hot pepper, grape, oriental melon, netted melon, peach, cherry tomato, plum, daikon, sweet persimmon, apple, sweet potato, mandarin, pear, and strawberry were -1.6, -0.5, -0.5, -0.7, -1.6, -1.6, -1.3, -0.8, -0.3, -1.1, -0.3, -1.7, -1.5, -1.5, -0.8, -1.5, and -$0.9^{\circ}C$, respectively; otherwise, supercooling points were -7.8, -3.7, -3.3, -4.9, -5.7, -4.6, -2.8, -3.3, -5.9, -4.2, -0.8, -4.7, -3.2, -3.7, -4.7, -4.2, and -$3.4^{\circ}C$, respectively. These results suggest that the ideal freezing temperature of crops could be estimated through freezing point depression because of their sugar content, and this technique should be used to maintain an optimum storage temperature. However, cold storage is complicated and further study is required because of the effects of long-term cold storage on the crops.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.169-182
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• 2014

This study investigates the physicochemical quality characteristics of tomato sauce added with different kinds of pimpinella brachycarpa. The results are as follows. The pH of tomato sauce added with freeze-dried pimpinella brachycarpa, in contrast to the tomato sauce with raw pimpinella brachycarpa, decreased as the addition quantity of the sample increased. As for sugar content, PBP0 with Pimpinella brachycarpa contained was shown to be the highest with 10.83. For chromaticity, all values (e.g, L, A and B) of tomato sauce added with pimpinella brachycarpa and with freeze-dried pimpinella brachycarpa decreased showing significant differences among the samples as the addition quantity of the samples increased. With increased addition quantity of the sample with freeze-dried Pimpinella brachycarpa, its water content decreased. PBP4, addition group with 4% of freeze-dried Pimpinella brachycarpa, was shown to be the highest DPPH free radical scavenging activity as 29.58. When adding Pimpinella brachycarpa to tomato sauce, a total number of micro-organisms decreased. In case of adding raw Pimpinella brachycarpa rather than freeze-dried Pimpinella brachycarpa, it created a further effect on an inhibitive action of growing and developing micro-organisms. In the preference of tomato sauce with Pimpinella brachycarpa, PBF2 with 2% of Pimpinella brachycarpa had the highest score as 5.1 for the color. For taste, 3.7, the lowest taste score, was shown in PBF1with 1% of Pimpinella brachycarpa. The overall preference revealed that PBF2 was the highest scoring 5.8.. PBF3 was scored highest with 5.9 for overall preference. From the comprehensive findings, 2~3% of the addition ratio between raw Pimpinella brachycarpa and freeze-dried Pimpinella brachycarpa in the production of tomato sauce is considered the most preferable.

• International Journal of Highway Engineering
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• v.3 no.4 s.10
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• pp.105-116
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• 2001

This study was performed to evaluate the characteristics of waste foundry sand (WFS) and the asphalt mixture made of a foundry waste sand. To estimate the applicability of WFS, chemical and physical properties were measured by XRF(X-ray fluorescent), and SEM(Scanning electronic microfilm). To improve the stripping resistance of WFS asphalt mixture, anti-stripping agents (a hydrated lime and a liquid anti-stripping agent) were used. To improve tensile properties and durability of WFS asphalt concrete mixture, LDPE(low-density polyethylene) was used as an asphalt modifier Marshall mix design, indirect tensile strength, tensile strength ratio(TSR) after freezing and thawing, moisture susceptibility and wheel tracking tests were carried out to evaluate performance of WFS asphalt concrete. Comparing with conventional asphalt concrete, WFS asphalt concretes showed similar or the better qualify in mechanical properties, and satisfied all specification limits. Therefore, it Is concluded that waste foundry sand can be recycled as an asphalt pavement material.

• Food Science and Preservation
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• v.16 no.6
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• pp.797-803
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• 2009

The effects of drying methods on the browning and moisture sorption characteristics of Rubus coreanus were studied. Fruits were steamed for 5 min at $100^{\circ}C$, dried by sun drying, infrared drying, or freeze drying, and powdered to a size of 20 mesh. Color values were measured and equilibrium moisture contents (EMC) were determined at $20^{\circ}C$, over a range of water activity ($a_w$) from 0.11 to 0.90. The browning indices $L^*$ and $a^*$ values were higher and lower, respectively, in freeze-dried Rubus coreanus compared with other samples. The $b^*$ value was greatest in freeze-dried Rubus coreanus. EMC tended to increase with increasing $a_w$ values, and a particularly sharp increment was observed above 0.75 $a_w$. The EMC of freeze-dried Rubus coreanus was significantly higher compared with the EMC of sun-dried and infrared-dried fruit at constant aw. The moisture sorption isotherms showed a typical sigmoid shape, and the Halsey, Kuhn, and Oswin models were the best fits for the sun-dried, infrared-dried, and freeze-dried powder isotherms, respectively. With respect to monolayer moisture content, the Guggenheim-Anderson-Boer (GAB) equation showed that the various drying methods yielded very different results, with monolayer moisture contents of 0.005 g $H_2O/g$ dry solid in infrared-dried and 0.019 g $H_2O/g$ dry solid in sun- and freeze-dried powders, respectively. These results indicate that the drying method affects the browning and moisture sorption characteristics of Rubus coreanus.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.5-16
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• 2012

The second scientific antarctic station of South Korea is under construction at Terra Nova Bay located in eastern Antarctica. Ground condition in the Antarctica is frozen in general, but there are seasonal frozen grounds with active layers sporadically. When the active layer is frozen, frost heaving occurs that might cause the differential movement of frozen ground and the failure of structures. Therefore, it is necessary to determine the frost heaving susceptibility of soils at Terra Nova Bay before starting antarctic station construction. This study presents experimental investigation of the frost heaving susceptibility of soil samples with variation of particle sizes and unfrozen water contents. The soil samples were taken from five different locations at Terra Nova Bay and physical properties, unfrozen water content, and frost heaving tests were performed. For the frost heaving tests, soil specimens were frozen with constant freezing temperatures at the top and with drainage at the bottom in order to stimulate the frost heaving. The frost heaving tests provide volume expansion, volumetric strain, and heaving rate which can be used to analyze the relationship between the frost heaving vs. particle size and the frost heaving vs. unfrozen water content. Experimental results show that the more the fine contents exist in soils, the more frost heaving occurs. In addition, the frost heaving depends on unfrozen water content. Experimental data can be used to evaluate the frost heaving susceptibility of soils at the future construction site in the Antarctica.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.154-163
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• 2003

This study was performed to examine the freezing and thawing properties of the high strength concrete using recycled coarse aggregate. The recycled coarse aggregate was replaced by 0%, 25%, 50%, 75% and 100% of natural crushed aggregate. The compressive strength of the concrete used recycled coarse aggregate was shown in more than $400kgf/cm^2$ at the curing age 28 days. The weight loss ratio by freezing and thawing was shown in less than 1% at all mix type. The pulse velocity and relative dynamic modulus were decreased with increasing the freezing and thawing cycles. Also, durability factor for the freezing and thawing were decreased with increasing the content of recycled coarse aggregate. But, recycled concrete replaced with recycled coarse aggregate 100% was shown in more than 60 by durability factor in freezing and thawing of 300cycles Accordingly, these recycled coarse aggregate can be used for high strength concrete.

• Reproductive and Developmental Biology
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• v.31 no.1
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• pp.43-48
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• 2007

This study was conducted to examine the characteristics of fresh and frozen semen, proliferating efficiency by AI, and the coat color of offsprings in Korean Native Striped Cattle (Bos namadicus Falconer, Chikso). Semen were collected from 6 heads of tiger-coated male Chikso. In vitro fertilization (IVF) was conducted with frozen-thawed semen and in vitro matured Korean native brown cattle (general Hanwoo) oocytes. Total 18 heads of Hanwoo and Chikso were inseminated using Chikso semen. Coat colors of total 40 offsprings produced by AI were evaluated. The characteristics of the fresh and frozen-thawed Chikso semen did not differ among individuals. In vitro fertilization rate of Chikso semen was not different from that of general Hanwoo semen. However, developmental rate to the blastocyst stage of IVF embryos was higher in Chikso semen (25.9%) than in general Hanwoo semen (p<0.05). There was no difference in conception rate after AI between Chikso and general Hanwoo. The coat colors of offsprings varied, only 42.5% (17/40 heads) of offsprings had tiger coat color. Futhermore, only 55% of offsprings produced from the tiger-coated recipients had tiger coat color. This result shows that proliferation of Chikso by AI is possible, but further research approaches may be needed to enhance the productivity of tiger-coated Chikso.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1451-1457
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• 2007

The physical and chemical characteristics of powders from hot air and freeze dried leaves and roots of Acorous calamus L. were investigated. Two parts, upper and lower, of leaves, and two kinds of roots, 4 and 6 years old, were dried at 30 and $40^{\circ}C$, freeze-dried, and ground to make powder. Contents of moisture, ash, crude fat, and crude protein in freeze dried powder of upper leaf were 4.87%, 6.73%, 2.22%, and 3.57%, respectively. Water absorption index (WAI) and water solubility index (WSI) in freeze dried powder of lower and upper leaves were 8.476 and 0.077 g/mL. Contents of chlorophyll a, chlorophyll b and total chlorophyll in freeze dried powder of upper leaves were 12.18, 16.86, and 29.11 mg/100 g, respectively. Contents of total and reducing sugar in freeze dried powder of 4 and 6 years roots were $111.89{\sim}119.21$ ppm and $5.02{\sim}5.22$ ppm, $109.92{\sim}114.65$ ppm and $5.21{\sim}5.32ppm$. Contents of total polyphenols and flavonoids in freeze dried powder of upper leaf were 125.02 and $21.02{\mu}g/mg$, respectively.

• Food Science and Preservation
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• v.12 no.5
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• pp.442-448
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• 2005

To develop efficient drying method, one of important process in manufacturing of Saengsik, uncooked food, the change of physicochemical characteristics and functional component contents of cereals dried by various drying methods was investigated. The proximate composition and dietary fiber content of rice, brown rice, glutinous rice and barley showed little changes during hot-air drying (50$\circC$, 55$\circC$, 60$\circC$) and freeze-drying. Yellowness(b) value of hot-air dried products was higher than one of freeze-dried products. The content of niacin was 0.77 mg% in milled rice, 1.84 mg% in brown rice, 0.68 mg% in glutinous rice, 1.00 mg% in barely dried by hot-air at 60$\circC$ and was lower than those of other samples. $\beta$-glucan content in barely was not changed by hot-air drying and freeze-drying method. In conclusion, hot-air drying would be recommended for barley having $\beta$-glucan, a kind of functional components and freeze-drying should be used for raw materials having heat-labile components such as niacin.