• 설비공학논문집
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• 제16권4호
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• pp.374-382
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• 2004

Diffuser design is crucial for water-chilled heat storage. Its impact on the system performance is more significant for the underground tank due to inherent limit on the aspect ratio and tank shape. The effect of diffuser shape on the performance of the water-chilled heat storage is numerically investigated. Three dimensional simulation has been conducted for fully incorporating the complex diffuser shape and the non-symmetric tank shape. Mixing at the inlet of the diffuser depends on the inlet Reynolds number, Froude number and the diffuser shape. Three types of the diffuser shape and the broad range of Reynolds number (Re=400, 800, 1200) and Froude number (Fr=0.5, 1.0, 2.0) are examined. The performance of the heat storage tank is evaluated by the thermocline thickness which is reverse to the degree of stratification. The radial regulated plate diffuser, which is the suggested diffuser shape in this study, shows the lowest thermocline thickness in the condition considered.

• 한국가금학회지
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• 제24권1호
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• pp.17-28
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• 1997

This experiment was carried out to investigate the effects of different chilling and packing methods on physico-chernical properties of cold-stored chicken breast and thigh meats. Dehoned chicken breast and thigh meats were chilled either air spray or ice-water immersion method. The chilled meats were either vacuum packed or atmosphere packed, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The pH of both immersion chilled meats and vacuum packed meats were higher than those of their counterparts(P<0.05). The pH of atmosphere packed meats increased as the storage period extended. The moisture contents of vacuum packed meats were remarkably higher than those of atmosphere packed meats. The pH of all treatments decreased as the storage period extended. The shear values of air spray chilled and vacuum packed breast meats were significantly higher than immersion chilled and vacuum packed ones. However, immersion chilled and atmosphere packed breast meats were significantly higher than those of air spray chilled and atmosphere packed breast meats. The shear values of immersion chilled and vacuum packed thigh meats were significantly higher than those of immersion chilled and vacuum packed thigh meats. In atmosphere packed thigh meats, air spray chilling method showed higher shear values than those of immersion chilled thigh meats. In thigh muscle, tenderness values tended to decrease as the storage period extended(P<0.05). Contents of water soluble proteins of vacuum packed and air spray chilled breast and thigh meats were higher than those of their counterparts as the storage period extended(P<0.05). The contents of water soluble proteins significantly decreased as the storage period extended. Salt soluble proteins of atmosphere packed breast and thigh meats were remarkably higher than those of vacuum packed ones(P<0.05). Total lipid contents of atmosphere packed and air spray chilled breast and thigh meats were higher than those of atmosphere packed and immersion chilled meats as the storage period extended. The vacuum packed meats were significantly higher in total lipid contents than those of atmosphere packed meats. The storage period decreased the total lipid contents of cold chicken, Major fatty acids in cold-stored chicken were oleic, palmitic, linoleic and stearic acids, regardless of chilling method. Unsaturated fatty acids of all treatments decreased, but saturated fatty acids increased as the storage period extended.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1099-1104
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• 2008

Recent year, mean energy consumptions of a people are higher than other country. And international oil price became over 120 dollar. This energy environment as well as energy war. Maybe, the Meteorological Administration is going to enforce scorching heatwave special report system from that come summer. Besides, 2008 summer, maximum demand power is expected by 64,240,000kW. The electric power equipment reserve rate appeared in to keep 12.5% level. Chilled water storage system witch is one of electric load administration system. Heat pump system used cooling tower heat recovery is advantage that use is possible to summer in small a public bath building. In this paper, we suggest that heat pump system by heat recovery using cooling tower when it is heating operation of ambient air temperature. To apply cooling tower heat recovery heat pump to chilled water heat storage type and achieved performance evaluation about operation. As a result, performance of heat pump system that about 121% in cooling mode, 138% in heating mode higher than KEPCO standard. And heating operation possible to ambient air temperature about $23^{\circ}C$, which of appear cooling tower outlet temperature about $13^{\circ}C$.

• 한국축산식품학회지
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• 제22권3호
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• pp.222-227
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• 2002

진공포장한 한우육 우둔부위를 1$^{\circ}C$, 4$^{\circ}C$의 일반공기순환 냉장고와 1$^{\circ}C$, 4$^{\circ}C$의 냉수에 침지하여 3, 7, 10, 14일 동안 저장하였을 때, 처리구간의 물리적 육색 (CIE L*, a*, b*)은 크게 변화하지 않은 것으로 나타났다. 그러나 육색소 산화를 나타내는 MetMb의 함량은 처리구간에 따라 변화를 보여 대조구 (4$^{\circ}C$-공기순화)가 가장 빠른 증가를 나타내었으며, 저장 14일째 T2 (4$^{\circ}C$-냉수침지)구가 유의적으로 (p<0.05) 낮은 MetMb함량을 보였다. 한편 이런 결과는 지방산화와도 유사한 경향을 보였는데, 대조구 (4$^{\circ}C$-공기순환)의 TBARS 수치가 저장기간 동안 가장 빠른 증가를 나타낸 반면, T3(1$^{\circ}C$-냉수침지) 구의 TBARS는 크게 증가하지 않았다. 이러한 결과는 냉수침지 방법이 지방산화와 육색소 산화를 억제시킬 수 있다는 것을 의미한다. 포장감량 또는 공기순환 처리구(control, T1)가 냉수침지 처리구(T2, T3)에 비해 높게 나타났다. 총 육색소 함량은 전 저장기간 동안 처리구간에 유의적(p>0.05)인 차이가 없었다. 이상의 결과를 종합해 볼 때, 한우육을 진공포장하여 1$^{\circ}C$ 냉수에 침지시켜 숙성시키는 방법이 지방산화를 억제시키고 육색소의 안전성을 유지할 뿐만 아니라 포장감량도 줄일 수 있는 숙성법이라고 사료된다.

• 한국축산식품학회지
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• 제22권3호
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• pp.228-233
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• 2002

본 연구는 진공포장 한우육의 냉수침지 숙성방법이 한우육의 연도 및 미생물증식에 미치는 영향을 구명하고자 수행하였다. 저장기간이 경과함에 따라 근절길이는 냉수침지 처리구가 저장 3일째 유의적(p<0.05)으로 긴 것으로 나타났으며, 저 장 3일째를 제외 한 저 장기간 동안 유의적 인 차이는 없었으나 대조구에 비해 긴 경향을 보였다. 또한 유리칼슘 농도에 있어서도 저장 7일 째 냉수침지 처리구가 유의적(p<0.05)으로 높게 나타났으며, 역시 저장 7일째를 제외한 저장기간 동안 유의적인 차이는 없었으나 대조구에 비해 높은 경향을 보였다. 한편 전단가와 근원섬유 소편화 지수에 있어서는 저장기간이 경과함에 따라 두 처리구간에 있어서 유의적인 차이는 나타나지 않았지만, 냉수침지 처리구가 상대적으로 낮은 전단가와 높은 소편화지수의 경향을 보였다. 이 같은 결과는 냉수침지 숙성이 일반공기순환냉장고의 숙성보다 근절의 길이를 길게 하고, 근형질내 칼슘의 농도를 높이며, 소편화 지수를 높게 한 결과 연도를 향상시킬 수 있다는 가능성을 제시한 것으로 사료된다. 덧붙여, 총세균수는 일반공 기순환냉장실에 저장한 것에 비해 냉수침지 처리구가 유의적(p<0.05)으로 낮은 것으로 나타나, 온도의 변이를 줄이는 것에 기인하여 미생물의 성장억제에도 효과적일 것으로 사료된다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.63-63
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• 2005

• 한국축산식품학회지
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• 제35권4호
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• pp.557-563
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• 2015

The present study was carried out to investigate the effects of soy protein hydrolysates (SPHs) addition on the quality characteristics of pork patties. The SPHs was prepared by subcritical water process (SWP) at 180℃ without holding time and mixed with the pork patty components at varying concentrations (0-3%), and the patties were stored at 4℃ for 14 d. As quality parameters, instrumental color, thiobarbituric acid-reactive substances (TBARS), pH, water holding capacity (WHC) and shear force were measured at the end of storage. Regardless of SPHs concentration, the addition of SPHs significantly manifested low L* and high a* values compared to those of untreated control (p<0.05). For b* value, addition of SPHs in the 0.5-1.5% was unaffected, while >2.0% of SPHs caused significantly lower b* than control (p<0.05). The color changes in pork patties with and without SPHs were also identified in visual appearance where the pork patties containing 0.5-2.0% showed bright red color which was comparable to brownish color of control and patties containing >2.5% SPHs. Lipid oxidation was delayed by the addition of 0.5-1.5% SPHs, while it was accelerated by the addition of 3% SPHs. The pH of patties increased with increasing concentration of SPHs, whereas there were no significant differences in WHC and shear force of patties. Consequently, the results indicated that the addition of 0.5-1.5% SPHs had a potential advantage in suppressing oxidative deterioration of fat-containing meat products during chilled storage.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.69-69
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• 2004

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2003년도 하계학술대회 논문집
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• pp.213-213
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• 2003

• 한국축산식품학회지
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• 제29권2호
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• pp.213-219
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• 2009

돼지고기 저지방 부위를 구성하고 있는 근육들 중 지방함량이 높은 5개 근육들의 냉장유통 중 품질변화를 예측하고자 냉장상태에서 14일 동안 저장하면서 근육별 이화학적 품질변화를 조사하였다. 수분함량, 지방함량, pH는 저장기간이 경과됨에 따라 유의적인 차이가 없었지만, 보수력에서는 supraspinatus, semitendinosus, longissimus dorsi 근육은 저장기간이 경과됨에 따라 유의적으로 증가하였다(p<0.05).포장감량은 모든 근육에서 저장기간이 경과점에 따라 감량이 증가하였지만(p<0.05), 가열감량과 경도는 저장기간에 따른 차이가 없었다(p>0.05). 결론적으로 돼지 저지방 부위 5개 근육들은 냉장저장 14일 동안 이화학적 특성의 변화정도에서 차이를 나타내었으며, 이러한 결과는 돼지 저지방 부위 근육을 활용한 구이용 상품화 추진에 기초 자료로 활용될 수 있을 것으로 사료된다.