• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.2
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• pp.55-60
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• 2009

Gochujang was prepared and fermented in 20 L new and reused Onggis, stainless and plastic containers. Quality attributes of the Gochujang were analyzed during the fermentation at room temperature. The microporous Onggicontainers, were found to promote the fermentative microbial growth, helping to create the desirable condition for good quality Gochujang. Reused Onggi resulted in Gochujang with higher content of amino nitrogen and free amino acids, and lower reducing sugar than new Onggi, which provided good sensory qualities in odor, taste and overall acceptability.

• Journal of the Korean Ceramic Society
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• v.55 no.2
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• pp.153-159
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• 2018

Porous ceramic plates were prepared from Onggi clay and bamboo charcoal powder at 1100 and $1200^{\circ}C$ and their porous properties and water absorption, and the cooling effect of porous plates, were investigated to produce eco-friendly porous ceramics for a self-cooling system that relies on the evaporation of absorbed water. Porous properties were dependent on the particle size of charcoal powder pore forming additive and the firing temperature; properties were also found to be dependent on the total pore volume, average pore size and porosity, which had values of $0.103-0.243cm^3/g$, 0.81 - 2.56 mm and 20.9 - 38.2%, respectively, at $1100^{\circ}C$ and $0.04-0.18cm^3/g$, 0.33 - 2.03 mm and 10.8 - 30.9%, respectively, at $1200^{\circ}C$. Cooling temperature difference of flowing air parallel to surface of porous ceramic plates fired with two kinds of charcoal powder at $1100^{\circ}C$ was $3.5-3.6^{\circ}C$ at $26^{\circ}C$ and 60% of relative humidity in a closed box. Cooling temperature difference was dependent on the number of porous plates and the distance between porous plates. A simple and eco-friendly cooling system using porous ceramic plates fired from Onggi clay and charcoal powder was proposed.