• 대한금속재료학회지
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• 제49권11호
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• pp.868-873
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• 2011

In this study, the fabrication of ultra fine grained Mo bulk was conducted. $MoO_3$ nanopowders were prepared by a high energy ball-milling process and then reduced at the temperature of $800^{\circ}C$ without holding time in $H_2$ atmosphere. The particle size of Mo nanopowder was ~150 nm and grain size was ~40 nm. The two-step process was employed for the sintering of Mo nanopowder to obtain fine grain size. The densification over 90% could be obtained by the two-step sintering with a grain size of less than 660 nm. For higher density, modified two-step sintering was designed. 95% of theoretical density with the grain size of 730 nm was obtained by the modified two-step sintering.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1623-1629
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• 2014

Dry-cured pork neck samples were stored at $10^{\circ}C$ for 90 days under vacuum packaging (VP) or modified atmosphere packaging (MAP; 25% $CO_2$+75% $N_2$) conditions. The pH, moisture, water activity, total aerobic bacteria, and Enterobacteriaceae counts of dry-cured pork neck products with MAP were significantly lower than those with VP (p<0.05) after 90 days of storage. However, CIE $b^*$ and 2-thiobarbituric acid reacted substance (TBARS) values of the pork product with MAP were significantly higher (p<0.05) than those with VP. Total aerobic bacterial counts and Enterobacteriaceae counts of samples with MAP were lower than those with VP after 30 days of storage. Sensory results indicated that aroma, flavor and tenderness scores of the samples with both VP and MAP decreased during storage and the scores after >60 days of storage were lower than those at Day 1. In conclusion, despite presenting higher lipid oxidation, the samples stored in packages containing 25% $CO_2$ for 90 days at $10^{\circ}C$ have lower bacterial counts than vacuum-packed samples. Therefore, further studies should be performed on the packaging of dry-cured meat at adjusted concentrations of $CO_2$.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.428-432
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• 2009

40 goat kid ribcages were held for 7 days in storage conditions ($4^{\circ}C$) and used to determine the effects of three different packaging methods (atmospheric air, vacuum and modified atmosphere package (MAP) 10:70:20 mixture of $N_2:O_2:CO_2$) on meat quality of the chops. L* was affected by the packaging method being lighter than MAP chops. The coordinate a* significantly increased during storage time. For MAP-packed chops and those kept in atmospheric air, b* increased markedly during storage time whereas it remained unaffected throughout storage when in vacuum packages. Final pH values ranged from 5.6 to 5.8 and no effects were found for either storage time or packaging method. WHC means were lowest for the three packaging methods on day 7 of storage and highest on day 1. Storage time increased water loss in vacuum treatments. Trained panel colour acceptability was lower at 3, 5 and 7 days than on day 1 of storage for atmospheric air treatment and vacuum packaging, while for the MAP treatment average values on days 5 and 7 were lower than those observed on days 1 or 3. Trained panel odour was lower for atmospheric air and vacuum packages at 3, 5, and 7 days storage than at 1 day, while no differences were found in trained panel odour acceptability for MAP packages. With reference to consumers, the MAP proposed in the present study is the chosen method for storing goat meat, rather than vacuum or atmospheric air packaging.

• 한국식품저장유통학회지
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• 제14권1호
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• pp.105-108
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• 2007

거창과 서울에 거주하는 소비자로 20대부터 60대까지 남녀 280명을 대상으로 MA 필름으로 포장한 포장구 사과와 포장하지 않은 대조구 사과의 신선함, 단맛, 신맛, 향미, 아삭거림, 씹힘성, 구매의사에 대한 기호도를 조사한 결과 20대에서 신선함, 아삭거림, 씹힘성과 구매의사에서 대조구보다 포장구의 기호도가 유의적으로 높게 나타났다. 30대는 신선함, 신맛, 향미, 구매의사에서 40대는 향에서, 50대에서는 단맛과 향에서만 대조구보다 포장구의 기호도가 유의적으로 높게 나타났다. 그리고 60대에서 신선함, 향미, 구매의사에서는 대조구보다 포장구의 기호도가 유의적으로 높게 나타난 반면, 단맛, 신맛, 아삭거림에서는 포장구보다 대조구의 기호도가 유의적으로 높은 것으로 나타났다. 모든 연령에서의 대조구와 포장구 사과의 기호도는 맛의 특성 중 신선함(p=0.0011), 향미(p=0.0002), 구매의사(p=0.0018)에서 유의적으로 포장구가 높게 나타났고, 단맛, 신맛, 아삭거림, 씹힘성에서는 기호도 차이가 나타나지 않았다.

• 한국축산식품학회지
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• 제38권3호
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• pp.593-605
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• 2018

The present study was undertaken to assess the efficacy of sapota powder (SP) as natural preservatives and its better utilization in food processing with the incorporation of various levels of SP (2, 4, and 6%) by replacing lean meat. Based on the sensory attributes, pork patties with 4% incorporation of SP was found optimum and selected for further storage studies with control under aerobic and modified atmosphere packaging at refrigeration temperature ($4{\pm}1^{\circ}C$) for 42 days for assessing its antioxidant and antimicrobial efficiency. During entire storage period, indicators of lipid oxidative parameters such as thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA) and peroxide value (PV) followed an increasing trend for control as well as treated products; however, treated product showed a significantly (p<0.05) lower value than control. A significantly lower (p<0.05) microbial count in treated patties than control was noted during entire storage. The sensory attributes are better retained in treated product as compared to control and even on $42^{nd}$ day, overall acceptability of treated patties was found to fall in moderately acceptable category (5.95 in aerobic packets and 5.91 in modified atmosphere packets). Therefore SP has potential to enhance antioxidant and antimicrobial properties of pork patties during storage.

• 한국식품저장유통학회지
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• 제14권5호
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• pp.457-461
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• 2007

영주산 '후지' 사과의 전처리 및 포장방법별 저장기간 동안 품질변호를 알아보기 위하여 사과를 5% $CaCl_2$ 용액에 15분 동안 침지한 후 완전히 건조시켜 $25\;{\mu}m$ 두께의 LDPE 필름으로 박스단위로 포장하여 $0^{\circ}C$의 농협 현지저온저장고에서 21주간 중량감소율, 경도, 적정산도, 가용성 고형분함량, 비타민 C함량, 부패율 조사하였다. 중량감모율, 경도변화, Vitamin C 변화, 부패율 등에서 칼슘처리과 필름포장을 병행한 처리구(Ca-MA)가 다른 처리구에 비해 저장 중 품질변화가 가정 적은 것으로 나타나 영주산 '후지' 사과 저장시 선도유지에 효과적인 것으로 사료된다.

• KIEAE Journal
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• 제10권6호
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• pp.11-19
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• 2010

To meet with the nation's policy of Green Growth, local governments are rushing to propose an ecological urban development plan. And although various studies stress on the need of ecological planning to harmonize development with preservation, we have come to a point in which a quantitative evaluation of how much ecological planning contributes to the environmental load is needed. Through the increasing tendency of making plans based on the development of IT technology, capability of gathering environmental data and scientific instrument, studies on ecological planning's effect towards environmental load has recently begun. This study aims to perform a quantitative evaluation on how ecological planning mitigate urban heat island in the region of Namyang-ju Wallsanli. Three theories were used to mitigate urban heat island ; White network, Green network and Blue network. As a result, the atmosphere temperature was reduced the whole site $1.1^{\circ}C$ and partly $7^{\circ}C$ and the mean radiant temperature was reduced the whole site $1.1^{\circ}C$ and partly $8.7^{\circ}C$ on the modified ecological landscape plan in summer. The PMV index is 0~1 in ecologically modified landscape plan otherwise almost 3 in landscape plan. This study has its limits on the fact that results may differ from the actual plan as the study was performed based on the land use plan and building plan. However, what is important is that it shows a quantitative result of the effect that ecological planning has on surrounding environment and reducing environmental load.

• Asian-Australasian Journal of Animal Sciences
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• 제32권3호
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• pp.421-429
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• 2019

Objective: In this study, the effects of vacuum (VP) and high-oxygen modified atmosphere ($80%\;O_2+20%\;CO_2$) packaging (HiOx-MAP) on physico-chemical and microbiological properties of minced water buffalo meat were investigated. Methods: After minced meat preparation, samples were packaged under VP and HiOx-MAP and stored at $2^{\circ}C{\pm}0.5^{\circ}C$ for 14 days. Samples taken on certain days were subjected to total aerobic mesophilic bacteria, total aerobic psychrotrophic bacteria, lactic acid bacteria, Pseudomonas, Enterobacteriaceae and yeast-mold counts as well as pH, color ($L^*$, $a^*$, and $b^*$) and thiobarbituric acid reactive substances (TBARS) analyses. Results: In minced water buffalo meat packaged under HiOx-MAP, TBARS value exceeded 1 mg malondialdehyde/kg on the 4th day of the storage. In VP samples, TBARS value remained close to initial TBARS value during storage. According to the findings, $a^*$ value was determined to be high in the HiOx-MAP samples within initial days of the storage. However, no significant changes in $a^*$ value were observed in VP samples during storage. In contrast, the mean value of $L^*$ was detected as higher in HiOx-MAP sample than VP samples. The count of psychrotrophic bacteria increased more than that of mesophilic bacteria during storage. The growth of Enterobacteriaceae and Pseudomonas was delayed in both the packaging methods. However, lactic acid bacteria exhibited more growth in VP samples compared to MAP samples. Conclusion: The lipid oxidation proceeded faster than expected in minced water buffalo meat packed with HiOx-MAP method. This situation adversely affected the $a^*$ value. On the other hand, similar microbiological results were obtained in both packing methods.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2004년도 총회및 심포지움
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• pp.67-72
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• 2004

Quality of fresh-cut tomato slices was compared during cold storage under various modified atmosphere packaging conditions. Chilling injury of slices in containers sealed with Film A was higher than with Film B; these films had oxygen transmission rates of 87.4 and 60.0 ml $h^{-1}\;m^{-2}\;atm^{-1}$ at $5^{\circ}C\;and\;99\%$ RH, respectively. While slices in containers with an initial atmospheric composition of air, $4\%\;CO_2+1\;or\;20\%\;O_2,\;8\%\;CO_2+1\;or\;20\%\;O_2,\;or\;12\%\;CO_2+20\%\;O_2$ showed fungal growth, slices in containers with $12\%\;CO_2+1\%\;O_2$ did not. Low ethylene in containers enhanced chilling injury. Modified atmosphere packaging provided good quality tomato slices with a shelf-life of 2 weeks or more at $5^{\circ}C$. Experiments were conducted to compare changes in quality of slices of red tomato (Lycopersicon esculentum Mill. 'Sunbeam') fruit from plants grown using black polyethylene or hairy vetch mulches under various foliar disease management systems including: no fungicide applications (NF), a disease forecasting model (Tom-Cast), and weekly fungicide applications (WF), during storage at $5^{\circ}C$ under a modified atmosphere. Slices were analyzed for firmness, soluble solids content (SSC), titratable acidity (TA), pH, electrolyte leakage, fungi, yeasts, and chilling injury. With both NF and Tom-Cast fungicide treatments, slices from tomato fruit grown with hairy vetch (Vicia villosa Roth) mulch were firmer than those from tomato fruit grown with black polyethylene mulch after 12 days storage. Ethylene production of slices from fruit grown using hairy vetch mulch under Tom-Cast was about 1.5- and 5-fold higher than that of slices from WF and NF fungicide treatments after 12 days, respectively. The percentage of water-soaked areas (chilling injury) for slices from tomato fruit grown using black polyethylene mulch under NF was over 7-fold that of slices from tomato fruit grown using hairy vetch under Tom-Cast. When stored at $20^{\circ}C$, slices from light-red tomato fruit grown with black polyethylene or hairy vetch mulches both showed a rapid increase in electrolyte leakage beginning 6 hours after slicing. However, slices from tomato fruit grown using the hairy vetch mulch tended to have lower electrolyte leakage than those grown with black polyethylene mulch. These results suggest that tomato fruit from plants grown using hairy vetch mulch may be more suitable for fresh-cut slices than those grown using black polyethylene mulch. Also, use of the disease forecasting model Tom-Cast, which can result in lower fungicide application than is currently used commercially, resulted in high quality fruit for fresh-cut processing. Experiments were conducted to determine if ethylene influences chilling injury, as measured by percentage of slices exhibiting water-soaked areas in fresh-cut tomato slices of 'Mountain Pride' and 'Sunbeam' tomato (Lycopersicon esculentum Mill.). Ethylene concentration in containers without ventilation significantly increased during storage at $5^{\circ}C$, whereas little or no accumulation of ethylene occurred in containers with one or six perforations. Chilling injury was greatest for slices in containers with six perforations, compared to slices in containers with one perforation, and was over 13-fold greater than that of slices in control containers with no perforations. An experiment was also performed to investigate the effectiveness of including an ethylene absorbent pad in containers on subsequent ethylene accumulation and chilling injury. While ethylene in the no-pad controls increased continually during storage of both 'Mountain Pride' and 'Sunbeam' tomatoes at $5^{\circ}C$ under modified atmosphere conditions, no increase in accumulation of ethylene was observed in containers containing ethylene absorbent pads throughout storage. The ethylene absorbent pad treatment resulted in a significantly higher percentage of chilling injury compared with the no-pad control. In studies aimed at inhibiting ethylene production using AVG during storage of slices, the concentration of ethylene in control containers (no AVG) remained at elevated levels throughout storage, compared to containers with slices treated with AVG. Chilling injury in slices treated with AVG was 5-fold greater than that of controls. Further, we tested the effect of ethylene pretreatment of slices on subsequent slice shelf-life and quality. In slices treated with ethylene (0, 0.1, 1, or $10\;{mu}L\;L^{-1}$) immediately after slicing, ethylene production in non-treated controls was greater than that of all other ethylene pre-treatments. However, pretreatment of slices 3 days after slicing resulted in a different pattern of ethylene production during storage. Ihe rate of ethylene production by slices treated with 1 L $L^{-1}$ ethylene 3 days after slicing was greater during storage than any of the other ethylene treatments. With slices pre-treated with ethylene, both immediately and 3 days after slicing, the rate of ethylene production tended to show an negative correlation with chilling injury. Chemical name used: 1-aminoethoxyvinylglycine (AVG).

• 한국식품저장유통학회지
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• 제2권2호
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• pp.225-232
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• 1995

In order to study the effect of modified atmosphere packaging(M.A.P.) and controlled atmosphere(C. A.) storage on keeping freshness of mushrooms (Agricus-bisporus). Mushrooms was packaged with polyethylene(P.E.) film (40${\mu}{\textrm}{m}$, 60${\mu}{\textrm}{m}$, 80${\mu}{\textrm}{m}$) and C.A. conditions(CO2 concentration of 2%, O2 concentration of 2%) and storage at 0$\pm$1$^{\circ}C$, RH(relative hummidity) 92$\pm$1%. Gas composition in film was changed rapidly at early of storage, but it kept a constant level after 14 days of storage, and then kept at the level of 6~9% CO2 and 2~5% O2. Weight loss was 5% in non-packed mushrooms after 3 days of storage, but P.E. film, CO2 treated, C.A. conditions were 5% after 21 days of storage. Flesh firmness of the mushrooms was continuously decreased throughout storage period and the lowest of flesh firmness changed was 80${\mu}{\textrm}{m}$-P.E. film packing. Discoloration of the piteous of mushrooms appears to be the most Important factors to determine its marketability, L value of it appears to be of the high values at P.E. film packing and C.A. conditions during period. Large amount of ethanol and acetaldehyde were produced from the 7 days during storage, large contents of mannitol and trehalose were at the 14 days and 7 days during storage.