• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1035-1041
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• 2000

Gamma irradiation was used to improve sanitation and quality of salted and fermented anchovy sauce. For commercial production, comparison with currently using sterilization methods, such as micro-filtration and heat treatment were also conducted. Control was prepared without irradiation and sterilization process. Microbiological, physiochemical, and sensory qualities were analyzed to observe the Quality changes during the storage. Irradiation at 5 kGy or above and micro-filtration process completely eliminated microorganisms detected in this study As irradiation dose increased, the color appeared brighter and irradiation at 5 kGy or above showed similar color L-value to that of sample treated with microfiltration. The color L, a, b-value of heat-treated sample always showed lower. The pH, salinity, and viscosity were sustained during storage. From the results of sensory evaluation, the samples treated with gamma irradiation and microfiltration obtained better scores than control or heat-sterilized. Gamma irradiation to salted and fermented anchovy sauce presented the best quality products among different sterilizing methods, especially at 5 kGy dose. Therefore, gamma irradiation can be successfully applied to commercial large scale production as a new sanitation technology with improved quality.

• Proceedings of the Korean Nutrition Society Conference
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• 2001.05a
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• pp.214.1-214
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• 2001

• Food Science and Preservation
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• v.14 no.2
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• pp.142-147
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• 2007

We optimized braising time to improve the storage quality of braised kidney beans. The beans were prepared with different heating times between 25 and 50 min. and then stored at $10^{\circ}C$ for 20 day. Physical, chemical, microbiological, and organoleptic quality indices were monitored throughout storage. Longer braising times yielded products with lower concentrated brine coverage. Bis resulted in higher soluble contents and slightly lower water activities. Excessive heating time exposed the kidney beans to air and caused rapid microbial growth on the surfaces of the beans, which negatively affected product quality. The longest heating time of 50 min. also resulted in a large increase in product hardness. A braising time of 30 min. was best for preservation, as good sensory quality was mainatained.

• Journal of Sensor Science and Technology
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• v.5 no.4
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• pp.17-24
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• 1996

Planar multi-junction thermal converters were fabricated for precise measurements of the ac voltage and current by an ac-dc transfer method. A heater and a thermocouple array were fabricated onto a sandwiched membrane, $Si_{3}N_{4}$ (200 nm) / $SiO_{2}$ (400 nm) / $Si_{3}N_{4}$ (200 nm), a thickness of $0.8\;{\mu}m$ and a size of $2{\times}4\;mm^{2}$, which is supported by a surrounding frame. The NiCr heater is located at the center of the membrane vertically. Hot junctions of $48{\sim}156$ pairs of thermocouples (Cu-CuNi44) are located near or onto the heater, and cold junctions are located onto the silicon frame. Output of the thermal converters for 10 mA dc input was $76\;mV{\sim}382\;mV$ dependent on a model, and short term stability of the outputs was ${\pm}5{\sim}15\;ppm$/ 10 min with 5 mA dc input. Responsivity in air was in the range of $3.9{\sim}14.5V/W$. Responsivity of the model BF48 in air which has 48 thermocouples was 2 times or greater than that of 3 dimensional multi-junction thermal converter in vacuum which has 56 thermocouples. AC-DC transfer differences with an input of 10 mA or less were less than ${\pm}1\;ppm$ in the frequency range from 5 Hz to 2 kHz, and about $2{\sim}3\;ppm$ at 5 kHz and 10 kHz.

• Journal of the Korean Vacuum Society
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• v.13 no.4
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• pp.182-188
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• 2004

Previous studies on the liquid Gallium ion sources used an electro-chemically etched tungsten wire with a coil-type heater. Such a structure requires excessive power consumption in the course of heating the liquid metal. In this work, a new structure is proposed that replaces the coil-type heater. It uses a Gallium reservoir made of six pre-etched 250$\mu\textrm{m}$ tungsten wires that surround the needle electrode. Gallium trading at the reservoir is observed to be much more stable, resulting in an improved beam stability.

• Resources Recycling
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• v.21 no.3
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• pp.48-55
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• 2012

Recently, the recycling with environmentally friendly method has been an issue for various fields. An effective removal method of coating layers from coated copper wires is one critical factor for recycling copper wire. We have adopted a high frequency heating routine for removing the coating layers on the coated copper wires, and attempted to find optimum conditions. The experimental results show that the copper wires should be maintained at or above $950^{\circ}C$ for rapid removal of the polyester. The simulation and experimental results are discussed with respect to the microstrucrual evolution during heating of the copper wires.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.327-332
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• 2001

Attempts were made to investigate the effect of gamma irradiation and heat treatment on quality changes of Bulgogi sauce during the storage at 4 and $20^{\circ}C$. Total acidity, Surface color, brix, microbial growth and sensory quality of test products were evaluated during storage. Total acidity of sauce did not change during storage at $4^{\circ}C$, whereas those of control and 4 kGy groups changed significantly during storage at $20^{\circ}C$. Gamma irradiation and heat treatment had little effect on brix of the suace during storage period. Surface color of control and 4 kGy group significantly changed during storage, especially at $20^{\circ}C$. Sucrose contents in sauce decreased during storage, while glucose and fructose contents increased. Sensory quality of sauces stored at $4^{\circ}C$ for 12 weeks was similar, except the control. Control and 4 kGy treated sauces stored at $20^{\circ}C$ for 6 week had detectable levels of off-flavor. Colifrom bacteria were not detected in sauces treated by either heat or gammma-ray. Total acrobic increases in colony counts were slower at $4^{\circ}C$. Yeasts or molds were not detected in sauces treated by heat or gamma-ray over 7-10 kGy. These results indicated that gamma irradiation over 7kGy or heat treatment of the sauce maintained acceptable quality.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.27-34
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• 2015

Heating patterns depending on the packaging materials were examined in order to investigate the causes of thermal deformation of packages used for ready-to-eat foods for microwave heating due to the non-uniformity of microwaves. Physical properties including tensile strength, heat-resistance and elongation of four different CPP grades were compared. High retortable CPP had higher sealing strength and heat resistance compared to the conventional CPPs. All CPP samples tested were proved to have melting temperatures around $160^{\circ}C$. However, they were all thermally deformed by microwave heating due to a limited penetration of microwave and non-uniform heating within the spicy sauce of high viscosity contained high salt, especially on the above the filling line and sealing edge of pouches. When the laminated stand-up pouches composed of G-PET/PET/PET/CPP and G-PET/PET/NY/CPP were retorted and microwaved, significant deformations were noticed in both samples after retorting. Besides, pouches contained titanium dioxide showed more intense thermal deformation than the control. When the $10{\mu}m$ aluminium foil was affixed on the pouch, small thermal deformation was observed only in the bottom layer. More studies are required to prevent the thermal deformation of packaging materials used for RTE foods during microwave heating by developing the technologies to increase the thermal stability of CPP layer and the modification of packaging design to modify the microwave access into the package.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.129-130
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• 2001

식육 제품 및 육가공품의 색은 그 식품의 품질과 선호도를 결정하는 중요한 척도로서 사용되며, 소비자는 밝은 척색의 육이나, 갈-회색의 가열한육 및 핑크색의 숙성된 육을 더욱선호한다(C. JO., et al. 2000). Hemo계 색소는 동물성 식품색소로, 적색은 주로 육 색소인 myoglbin과 혈색소인 hemoglobin에 의한 것이다. 육색소인 myoglobin은 공기 중에 방치하면 산소와 결합하여 Oxymyoglobin으로 변화하여 선명한 선홍색을 띄게 된다. 육류를 가열하면 일부 산화되지 않고 있던 myoglobin이 Oxymyoglobi을 거쳐 metmyoglobin으로 된다. (중략)

• Food Science of Animal Resources
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• v.22 no.2
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• pp.137-144
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• 2002

Pork loins that retailed in market were used as experimental samples. Some pork samples in raw state were packaged with PVDC in either aerobic or vacuum condition. The other pork samples were cooked until core temperature reached at 70$\^{C}$ and then packaged immediately in the same way with the raw samples. After these samples were irradiated by electron beam 6 kGy, the samples were stored in a refrigerator (2∼4$\^{C}$). Identification and quantification of cholesterol oxides were performed at 0 and 7 days. The results were following. During the early stage of storage, cholesterol oxides were not produced from the raw meat samples, but with the passage of storage time,7 $\alpha$-hydroxycholesterol, 7$\beta$-hydroxycholesterol, 7-ketocholesterol, 20 $\alpha$-hydroxycholesterol, $\beta$-epoxide and $\alpha$-epoxide, which were not produced during the early stage of storage, were produced. The production of cholesterol and lipid oxidation products were significantly higher (P<0.05) in the meats with aerobic packaging than those with vacuum packaging, Cooked meat after irradiation showed 7 $\alpha$-hydroxycholesterol, 7 $\beta$-hydroxycholesterol, $\alpha$-epoxide and cholestanetriol on the 7th day of storage, although those chemicals were not produced during the early stage of storage. Production of cholesterol oxides was significantly increased (P<0.05) with the passage of storage time for all treatments, and showed significantly lower value (P<0.05) with the vacuum packaging than these for aerobic packaging. Species of cholesterol oxides from irradiated meat after cooking were similar to those from cooked meat after irradiation. Collectively, it was found that the production of cholesterol oxides was more easily affected by packaging condition than irradiation.