• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.478-485
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• 2017

The effect of high carbon dioxide and ethylene treatment on postharvest ripening regulation of red kiwifruit (Actinidia melanandra) was investigated during cold storage. Physio-chemical properties such as weight loss, firmness, SSC, acidity, and market quality were analysed in red kiwifruit held at $10^{\circ}C$ compared to the fruit treated with carbon dioxide and ethylene during 75 days of storage. No significant weight loss was detected in red kiwifruit treated with carbon dioxide until 75 days of storage while the most rapid loss was found in fruit treated with ethylene. In ethylene-treated fruit, the firmness was dramatically reduced from 4.2kg on the first day to 1.2 kg after 27 days of storage at $10^{\circ}C$. However, the firmness of the carbon dioxide-treated fruit was 1.8kg after 54 days of storage. The highest level of SSC(%) was investigated within the 27 storage days at $10^{\circ}C$ for fresh red kiwifruit treated with exogenous ethylene, whereas the carbon dioxide-treated fruit exhibited a greatly increased SSC after 64 days. The carbon dioxide-treated red kiwifruit maintained statistically(p<.01) higher levels of acidity compared to the control and the exogenous ethylene-treated ones during 41 days of storage at $10^{\circ}C$. The SSC/Acid ratio of fruit treated with carbon dioxide was significantly lower (p<.01) maintained than the other two treatments (ethylene-treated and control fruit)throughout the 75-day experiment. Based on the quality characteristics of postharvest red kiwifruit, it could be concluded that the carbon dioxide treatment significantly delayed the ripening process and maintained the market quality of harvested red kiwifruit, which can be a potential application for commercial use in the kiwi industry.

• Food Science and Preservation
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• v.9 no.2
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• pp.131-136
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• 2002

Quality changes of satsuma mandarin (Citrus unshiu Marc. var. miyagawa) during storage by storage warehouse were investigated. Citrus were treated with 2000-folds diluted iminoctadime-triacetate solution and 1.5% chitosan with 0.5% CaCl$_2$ solution, and were at 30$\^{C}$ for 24 hr before storage. The citrus of about 12kg/26L plastic container were stored at room temperature, and at 4$\^{C}$ with 87% relative humidity. Decay ratio of citrus with precise temperature and humidity control were lower than the others during storage. Penicillium italicum Monilia candida Alternara citri, Mucor hiemalis, Phomopsis citri Botrytis cinerea, Phoma citricarpa Clomererella cingulata, Penicillium digitatum were identified as putrefactive microorganisms in citrus storage. Weight loss, moisture content of peel and flesh were decreased slowly during storage. 24% of original acid content were decreased at room temperature on 120 days storage, compared to 15∼18% loss on cold storage. Total sugar of citrus was decreased rapidly after 90 days, and vitamin C content were also decreased rapidly after 60 days during storage.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.474-477
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• 2006

Dynamic rheological properties of commercial 0.8, 1.0, and 1.2% gums [carboxylmethylcellulose (CMC), guar gum, hydroxypropylmethylcellulose (HPMC), tara gum, and xanthan gum], which can be dissolved in cold water, were investigated by small-deformation oscillatory measurements. Magnitudes of storage (G') and loss (G") moduli increased with increasing concentration of gum solutions except for xanthan gum. Guar gum exhibited greatest G' and G" values among all gums except for G' value at 0.8% concentration. Slopes of G' and G" decreased with increasing concentration of gum solutions except for xanthan gum. Tan ${\delta}$ (G"/G') values decreased with increasing concentration of gum solutions except for xanthan gum. Tan ${\delta}$ values of xanthan gum solutions were much lower than those of other gum solutions, indicating that xanthan gum solutions were predominantly more elastic than viscous.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.57-67
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• 2001

This study was implemented with pH, Color, Water-holding capacity, Drip loss, Cooling loss, Shear force, and Panel test to compare fresh meats cold storage of Bonggye-ri, DuDong-myeon, Ulsan. and the followings are summary of the result. 1 For the change of pH by the period of storage(temperature of 2$^{\circ}C$), there was a considerable difference between 1, 3rd day and 5, 7th day, but it wasn't a great difference 2 There wasn't any considerable difference for L*, a*, b* value by the period of storage. 3 The drip loss increased by the period thus a difference was existed, no difference was shown in cooking loss. 4. There was no considerable difference in shear force by the period. 5 For the total preference of panel test, the 1st day was the best followed by 3rd day, and no considerable difference was seen between 3 and 5, 7th day.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.256-261
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• 2017

The effects of temperature and length of cold storage on the quality maintenance of fresh "Gold" kiwifruit were investigated. Physio-chemical properties were analyzed in kiwifruit held at $2^{\circ}C$ and $6^{\circ}C$ temperatures compared to fruit at room temperature ($20{\sim}28^{\circ}C$) during 8 weeks of storage. Low temperatures ($2^{\circ}C$ and $6^{\circ}C$) significantly delayed softening and soluble solids content (SSC) accumulation compared to higher temperature ($20{\sim}28^{\circ}C$). Physico-chemical properties of fruits, including weight losses, firmness, SSC, titratable acidity (TA), SSC/TA ratio, and flesh color properties were monitored during storage. Fast firmness loss was detected in fruit stored at higher temperatures compared to low temperature ($2^{\circ}C$). Similar results were observed for acidity according to storage temperature and length of cold storage, whereas SSC increased to the limited values (%Brix) during storage. The soluble solids content (SSC) increased markedly during the first 60 days of storage and remained almost constant thereafter for all treatments. SSC accumulation rates decreased from 5 weeks after storage probably due to differences between initial and ripe kiwifruits, and SSC decreased with each passing week due to natural starch conversion over time. The SSC/acid ratio increased from 18 to 27 until 5 weeks after storage and then slowly declined in all kiwifruit stored at different low temperatures. Sensory evaluation results showed no differences in kiwifruit flesh color stored at two storage temperatures of $2^{\circ}C$ and $6^{\circ}C$.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.633-640
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• 2008

In this study, the effects of feeding citrus byproducts on various qualities of pork during cold storage were investigated, such as water holding capacity, drip loss, meat color, storage stability, rancidity, and antioxidant activity. Pork samples (195 days old, $115{\pm}3\;kg$, female) used for the experiment was divided into three groups: T0(pigs not fed citrus byproducts), T1(pigs fed 3% and 5% citrus byproducts during growth and the finishing period, respectively), and T2(pigs fed 6% and 10% citrus byproducts). The loin used for the experiment was obtained from 5 pigs of each group, vacuum packaged, and then stored at $3^{\circ}C$ for 4 weeks. There was no difference among T0, T1, and T2 for pH, water holding capacity, or drip loss. As for the meat color of the loin, T1 and T2 showed higher redness($a^*$ value) during early chilling but showed higher yellowness($b^*$ value) during late chilling. T1 and T2 showed higher electron donating ability and lower volatile basic nitrogen, total plate count, and TBA values than T0, regardless of the chilling period. Thus, feeding citrus byproducts improves the storage stability of chilled pork in terms of rancidity and antioxidant activity.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.4
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• pp.499-505
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• 2011

The purpose of this research was to study the characteristics of Hanwoo (Korean native cattle) beef fed without mugwort (T0) and Hanwoo beef fed with mugwort (T1) during storage at$3{\pm}1^{\circ}C$ for 50 days. During cold storage, $a^*$ and $b^*$ value of meat color for T1 decreased slowly compared to those of T0, there was significant difference between T0 and T1 after 40 days (p<0.01). The shear force value of T0 and T1 decreased (p<0.001), and the drip loss and cooking loss of T0 and T1 increased (p<0.05). However, there was no significant difference between T0 and T1. During refrigeration period, the volatile basic nitrogen contents of T1 slowly increased compared to T0, there was significant difference between T0 and T1 after 50 days (p<0.01). The total plat count and thiobarbituric acid value of T1 slowly increased compared to T0, and there was significant difference between T0 and T1 after 30 days (p<0.01). Further, the decrease of the antioxidant activity of T1 was delayed, there was significant difference between T0 and T1 after 40 days (p<0.05). There was no significant difference of taste, juiciness, or tenderness of cooked meat between T0 and T1. The aroma and palatability of cooked meat for T1 fed with mugwort were significantly superior than those of T0 at day 30 after storage (p<0.05).

• Applied Biological Chemistry
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• v.38 no.3
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• pp.239-247
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• 1995

The improvement of distribution system and freshness prolongation of crisphead lettuce were carried out through vacuum cooling and distribution under the low temperature. Lettuce that vacuum-cooled and transported by cold storage car was shown better freshness than that distributed by conventional method when they arrived at cunsuming area. And it took $10{\sim}17$ hours until their temperatures arrived at same temperatures when they were stored at $0{\sim}15^{\circ}C$ cold storage room. It was cooled to $1^{\circ}C$ after 27 minutes with vacuum cooling apparatus. The weight loss of lettuce that vacuum cooled and transported by cold storage car was below 5% after 30 days cold storage. And ascorbic acid and chlorophyll retentions were 86% and 52%, respectively. The shelf-life of crisphead lettuce, distributed by vacuum cooling and cold storage car transportation, was 5 days at $15^{\circ}C$ and over 40 days at $0^{\circ}C$, respectively. However, when it was distributed by conventional method, it was only 3 days at $15^{\circ}C$ and 20 days at $0^{\circ}C$, respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.2
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• pp.93-98
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• 2011

Saline corrosion is one of the major degradation mechanisms for stainless steel type 304 (SS304) dry storage cask during the spent fuel interim storage period. Slow strain rate test (SSRT) and neutral salt spray test (NSS) were performed at $85^{\circ}C$ and $200^{\circ}C$ with 0.5 wt% sodium chloride mist sprayed on the cold-rolled SS304 specimens of different degrees of reduction in this study. The weight changes of the NSS specimens tested at $85^{\circ}C$ for 2000 hours differed greatly from those at $200^{\circ}C$. The weight loss of NSS specimens was not significant at $85^{\circ}C$ but the weight gain decreased gradually with increasing the cold-rolled reduction. The yield strength (YS) and ultimate tensile stress (UTS) values obtained from the SSRT tests for lightly cold-rolled specimens in the salt spray environment at $85^{\circ}C$ and $200^{\circ}C$ are slightly lower than in air. But for those with 20% reductions, the specimen strengths were no longer changed by the saline corrosion. The preliminary results demonstrated that the quality and performance of cold-rolled SS304 is acceptable for fabrication of dry storage casks. However, more work on the corrosion behavior of cold-rolled stainless steel in the saline atmosphere is needed to better understand its long-term performance.

• Transactions of the KSME C: Technology and Education
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• v.2 no.1
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• pp.65-72
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• 2014

The purpose of this study is to design a heat insulator for reducing available energy loss in stratified thermal storage tank. Heat insulator is operated by buoyancy effect from density difference between hot and cold water without extra equipment. Analysis model using the Matlab Simulink was developed to estimate the internal temperature distribution in thermal storage tank and also used to select proper material and thickness of the heat insulator. Operational feasibility was confirmed through reduced scale experiment. As a result, heat insulator can effectively delay the formation of thermal boundary layer between hot and cold water. In reduced scale experiment, heat insulator can preserve additional 1540J of available energy. When applied to the real thermal storage tank, increase of 6% thermal storage efficiency can be expected.