• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.762-766
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• 1990

The effect of storage conditions on the oxidative stability of cholesterol in butter was studied by identifing cholesterol oxides by TLC. Experimental variables for storage conditions were packaging(packaged and unpackaged), storage temperature(ambient and refrigerated), light source(dark, fluorescent and ultraviolet), and storage period(2, 4, 6, and 8 weeks). No cholesterol oxides were detected from packaged butter under all storage conditions. When unpackaged butter was stored under darkness at ambient and refrigerated temperatures, cholesterol oxides were not detected even after 6 weeks of storage, but small amounts of $7{\alpha}-and\;7{\beta}-hydroxycholesterols$ were detected after 8 weeks of storage. When unpackaged butter was stored under ultraviolet light at ambient temperature, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$ cholestane-triol, and cholesterol epoxide were detected after 2 weeks of storage, and when fluorescent light was used instead of ultraviolet light, the same species of cholesterol oxides were detected after 6 weeks of storage.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.543-548
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• 2006

The effects of food grade fructooligosaccharide (FOS), isomaltooligosaccharide (MOS), galactooligosaccharide (GOS), and inulin on the growth of five strains of bifidobacteria in fermented milk were investigated. Their effect on culture viability during refrigerated storage was also determined. FOS showed the highest growth-promoting activity for all bifidobacteria except for Bifidobacterium bifidum. Growth rates of B. adolescentis, B. breve, and B. infantis were stimulated by oligosaccharides and inulin, whereas B. longum growth was stimulated by the oligosaccharides but not inulin. In contrast, growth of B. bifidum was enhanced only by inulin. Both acetic and lactic acid production by Bifidobacterium spp. was also enhanced in the presence of 5.0% oligosaccharides. The viability of bifidobacteria cultured with oligosaccharides and inulin, particularly with FOS, was significantly higher than control cultures after 4 weeks of refrigerated storage. The utilization of oligosaccharides is likely to enhance the growth rate, activity, and viability of bifidobacteria.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.431-436
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• 2006

Effects of vacuum packaging and modified atmosphere packaging (MAP) on shelf life of selenium-supplemented chicken meat during refrigerated storage were examined. Body weight and feed efficiency were unaffected by dietary selenium level. Dietary treatments and packaging methods had no significant effects on level of microbial growth, lightness, and metmyoglobin content. MAP decreased purge loss (10.9-34.5%) and lipid oxidation (15.2-15.9%) more efficiently than vacuum packaging. Broiler chicks supplemented with ${\alpha}$-tocopherol or ${\alpha}$-tocopherol + selenium had similar TBA values. Dietary supplementation of 4 and 8 ppm selenium reduced lipid oxidation, and this effect was less significant in MAP breast meat.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.372-381
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• 2003

This study aims to find out the optimized insulation thickness of refrigerated warehouse with different envelope structures (RC and PC wall) and insulation materials (urethane and icynene). Each of them is compared according to the thickness of insulation (100, 150, 200 mm/50 or 250 mm) and the temperature of cold storage room (0, -6, -15$^{\circ}C$). As results, it is proved to have the best economical efficiency in life cycle cost when PC wall with thickness of 100 mm (0 and -6$^{\circ}C$) and 150 m (-15$^{\circ}C$) urethane, respectively, are applied.

• Korean Journal of Clinical Pharmacy
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• v.9 no.1
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• pp.71-76
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• 1999

The stability of penicillin G potassium injection after reconstitution was evaluated in two different diluents of sodium chloride $0.9\%$ and dextrose $5\%$ in water stored at room temperature or refrigerated condition. The concentrations of penicillin G, stored for 24 hours at room temperature or for 10 days at refrigerated condition, were determined by HPLC. Also the pHs of the reconstituted solutions were monitored. The concentrations and pHs of penicillin G potassium 500,000 U/ml injection after reconstitution gradually decreased in all conditions. Stored at room temperature after reconstitution, a new peak which suspected as degradation products of penicillin G was detected in 5 hours in sodium chloride $0.9\%$, 4 hours in dextrose $5\%$ in water. At refrigerated condition, the new peak was detected in 4 days in both sodium chloride $0.9\%$ and dextrose $5\%$ in water. The degradation products of penicillin G allergy have been thought to be one of the substances responsible for evoking allergic reactions. In conclusion, the penicillin G potassium 500,000 U/ml injection after reconstitution was stable for 4 hours in sodium chloride $0.9\%$ 3 hours in dextrose $5\%$ in water solution at room temperature. At refrigerated condition, both solutions were stable for 3 days after reconstitution.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.39 no.12
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• pp.36-42
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• 2010

• Journal of Digital Convergence
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• v.18 no.4
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• pp.55-65
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• 2020

The factors for service quality improvement of frozen and refrigerated warehouses are derived and the differences in perception about service quality improvement between shippers and operators of frozen and refrigerated cargos are analyzed. The objective of this study is to propose quality improvement measures for frozen and refrigerated cargo services using the importance-performance analysis (IPA). As a result, 15 analysis factors were derived. It was found through independent sample t-test that there is no difference in perception about quality improvement between shippers and operators. Furthermore, four top priority investment areas were derived from the IPA: maintaining temperature and humidity, securing variable storage space, on-time stocking and releasing, and providing information service. Meanwhile, inventory management service ability, on-time stocking and releasing, and reliable cargo storage ability needed urgent improvement. This study has industrial implications in that it proposes practical improvement measures for service quality improvement.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.248-254
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• 2015

We conducted this study to investigate the amount of RS and cooking characteristics of the commercial extrusion-cooked noodles. Ten kinds of noodles were selected and grouped according to the storage conditions; dry noodles (3), refrigerated noodles (2), freeze noodles (4), and dry noodle made from wheat flour as a control (not extrusion-cooked). The total starch of commercial noodles ranged from 62.50% to 84.13%, Refrigerated Naengmyeon and dry Dangmyun had high proportions of total starch (respectively 84.13% and 80.13%, respectively). The amounts of apparent amylose ranged from 25.01% to 42.93% and RS ranged from 0.61% to 5.99%. A high proportion of the total starch was rendered digestible by extrusion cooking, and a small amount of RS remained in the samples. Dry Dangmyun had the highest percentages of RS (5.99%), followed by refrigerated Naengmyeon C (2.41%) and dry Jjolmyeon (1.94%), and those of the other noodles were lower than that of the control (1.86%). Cooking properties and texture measurements were evaluated. Cooking loss and turbidity of cooking water were highest in dry Jjolmyeon and dry Naengmyeon. There was little cooking loss in dry Dangmyun and freeze rice noodles. In particular, dry Dangmyun and refrigerated Naengmyeon C containing high amounts of RS and amylose had relatively high measurements of hardness and tensile strength.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.113-118
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• 2006

The effects of dietary Rhus verniciflua Stokes supplementation (0%, 2%, 4% and 6%/feed) on meat color, water-holding capacity (WHC), lipid oxidation and fatty acid composition in m. longissimus from Hanwoo (Korean cattle) beef during refrigerated storage were investigated. The $L^*$, $a^*$, $b^*$ and $C^*$ values of 4% group were significantly (p<0.05) higher than those of the other groups for 7 days of storage. The $a^*$, $b^*$ and $C^*$ values declined gradually during storage in all of the groups and the decline was more rapid in control group. The metmyoglobin (%) was significantly (p<0.05) increased during storage time in all of the groups, but the 4% group had a lower rate of metmyoglobin accumulation during storage. WHC was significantly (p<0.05) higher in the 2% and 4% groups than in the other groups. The TBARS (thiobarbituric acid reactive substances) value of day 0 was not significantly (p>0.05) different among 4 diet conditions, but the TBARS value after 5 days of storage was significantly (p<0.05) higher in the control group than in other groups. The proportions of C18:1, MUFA, UFA and MUFA/SFA ratio were significantly (p<0.05) higher in the meat from Rhus verniciflua Stokes-supplemented Hanwoo than in the control group. Consequently, the meat from Rhus verniciflua Stokes-supplemented Hanwoo showed higher color stability, WHC, unsaturated fatty acids and retarded lipid oxidation compared to the control meat. In particular, dietary Rhus verniciflua Stokes supplementation with 4% extended storage life compared to the other groups.

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.115-122
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• 1990

Effects of 7.5% potassium sorbate and/or 1% ascorbic acid dip on she]f-life of chicken parts stored at $4^{\circ}C$ was investigated. There was no remarkable difference in the microbial growth between 1% ascorbic acid dipped chicken parts and untreated chicken parts. Off-odor developed after 8 days storage and bacterial spoilage was occurred after 12 days storage. 7.5% potassium sorbate dip significantly retarded mesophilic and psychrotrophic counts compared with untreated, markedly reduced growth rate of Enterobacteriaceae. Fecal coliforms were not detected and bacterial spoilage was not occurred until 21 days storage. off-odor developed after 19 days storage and color was not significantly deteriorated until 21 days storage. Additional effect of 7.5% potassium sorbate and 1% ascorbic acid dip was found on retarded mesophilic, psychrotrophic and Enterobacteriaceae counts compared with 7.5% potassium sorbate dip alone. Bacterial spoilage was not occurred until 21 days storage. off-odor developed after 21 days storage and color was not significantly deteriorated until 21 dayss storage.