• Food Science and Preservation
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• v.11 no.1
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• pp.7-11
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• 2004

To examine the effect of storage condition on the quality and microbiological change of strawberry “Minyubong”, the rate of weight loss, decay rate, pH and titratable acidity, and microbial (total bacterial count, mold and yeast) changes were determined during storage. Strawberry fruits were packaged with low-density polyethylene (LDPE). Strawberries were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was effective on the decrease of decay rate of strawberry as well as the rate of weight loss, compared with the non-packaged. Microbial changes of strawberry stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging affected the microbial change, resulting in retarding the growth of total bacteria as well as mold and yeast, compared with the non-packaged, regardless of storage temperature. These results indicate that storage of strawberry fruits wrapped with LDPE at 4'C should be recommended in terms of quality as well as its shelf-life.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.415-424
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• 2014

This study was carried out to determine the effect of storage condition, such as temperature or relative humidity (RH) in home-style refrigerator, on the change of quality traits and storage characteristics of Hanwoo M. longissimus to find out the condition for prolongation of shelf-life with maintaining the meat quality for consumers. Samples were sliced in $1{\pm}0.2cm$ thickness, and packed in foamed polystyrene tray with linear low-density polyethylene (LLD-PE) film to simulate the pre-packed Hanwoo loin sold in retail market, then stored in home-style refrigerator ($5^{\circ}C$/17% RH, Control), and chambers of $5^{\circ}C$/55% RH (T1), $5^{\circ}C$/85% RH (T2), and $-1^{\circ}C$/99% RH (T3), respectively. Quality traits (color, pH, water holding capacity, shear force and grilling loss) and storage characteristics (thiobarbituric acid reactive substances, volatile basic nitrogen and total microbes) were measured at 1, 4, 7, 14 and 21 days after storage. Lightness of Hanwoo loin stored in T1, T2 and T3 were higher than that of control until 14 days of storage, however at the end of storage (21 days) control showed significantly higher than other treatments (p<0.05). Redness and Yellowness of Hanwoo loin samples stored in T1 and T3 were significantly higher than others during all storage period (p<0.05). The water holding capacity (WHC) of control was significantly higher than others until 14 days of storage (p<0.05), however, Hanwoo loin stored in T2 was the highest ($63.64{\pm}7.62kg/cm^2$) at 21 days of storage. Hanwoo loin stored in T1 showed significantly lower shear force than others during all storage period (p<0.05). There was no consistent tendency in pH and grilling loss during storage in all treatments. Hanwoo loin stored in T1 showed lower TBARS value than others during storage period, however there was a rapid increase to $0.34{\pm}0.27mg$ malonaldehyde/kg meat at 21 days of storage. And, all the treated samples (from T1 to T3) showed significantly lower VBN values at 21 days of storage (p<0.05). The population of total aerobic microbes were significantly increased in all treatments as storage period increasing, and the population of T3 ($2.28{\pm}0.57logCFU/g$) was the lowest at 21 days of storage (p<0.05). From those results, it could be predicted the better storage condition to maintain the meat quality and prolong the shelf-life of Hanwoo loin by lowering the temperature and adjusting the humidity about 55%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.84-88
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• 2008

This study was carried out to develop the methods for efficient extracting and stabilization of anthocyanin pigments in black colored soybean. The optimum solvent concentration for the highest pigment extraction from seed coat of black colored soybean was 60% MeOH with 0.1% HCl in laboratory test. The higher temperature of the solvent until $60^{\circ}C$ led to better extraction efficiency of anthocyanin. The anthocyanin extracts maintained almost its stability in strong acidity area whereas it destroyed markedly over pH 4. Also anthocyanin extracts was stable for a while under weak light condition, but it showed rapid degradation of pigment color and markedly decreased HPLC value for anthocyanin content after one month storage days. In case storage temperature and instrument, glass vessel on low temperature ($4^{\circ}C$) was good storage condition among some treatments. And C3G was more stable than other pigments.

• Food Science and Preservation
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• v.12 no.3
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• pp.204-208
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• 2005

This study was conducted to investigate the effects of temperature and packaging on the quality characteristics of hot-water extract from Acanthopanax senticosus. The herb samples, ground and sifted($8{\sim}20$ mesh), were extracted by a boiling($100^{\circ}C$) water under the atmospheric pressure for 2 hrs. The extract was packed with out nylon PE(0.08 mm) pouch and kept under the condition(40 and $60^{\circ}C$) for 10 days. The reduction of turbidity, pH, polyphenol amount and DPPH radical scavenging activity of extract were retarded by packaging under the low temperature. Titratable acidity was increased with packaging at high temperature. Soluble solid content was not affected by packaging and temperature condition. The changes of quality characteristics followed the first-order reaction rate. Arrhenius equation was applied to determine the effects of temperature on the reaction rate constant, showing high $R^2$. These results suggested that packaging under lower temperature can be utilized for maintaining the quality of A senticosus extract.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.295-307
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• 2009

The principal objective of this study was to develop and standardize a preparation method for low-sodium tomato jangachi (traditional Korean pickle) via short-term fermentation with immature green cherry tomatoes. In order to determine the preferred concentrations of soy sauce and soaking temperatures of immature cherry tomato pickles in different stages of storage, we conducted an analysis of physico-chemical characteristics and microbiological properties, and also performed a preference test on samples of immature green cherry tomato pickles. Immature cherry tomatoes were prepared in three different soy sauce concentrations --20, 40, and 60%-- and three different soaking temperatures --60, 80, and 100$^{\circ}C$-- and then stored for 28 days at 5$^{\circ}C$. As a result, the pH increased significantly with increases in the amount of soy in the dipping solution (p<0.05). The saltiness was maintained at levels of approximately $0.17{\sim}0.28%$ (20% group), $0.32{\sim}0.67%$% (40%group), $0.48{\sim}1.00%$ (60% group) during storage periods. These results show that the saltiness of immature cherry tomato pickles was substantially lower than that of commercial pickles. The contents of reducing sugar and lightness decreased significantly with increasing concentrations of soy dipping solution. The redness and yellowness values of the tomatoes decreased significantly with increasing concentrations of soy sauce. Additionally, the lower the concentration of soy sauce used, the more rapidly the hardness of the immature cherry tomato pickles was reduced at 100$^{\circ}C$. PME activity moved within a narrow range, and then stabilized during the storage period. With regard to the results of the consumer preference test, 20%-100$^{\circ}C$ was the most preferred condition overall, 40%-80$^{\circ}C$ was the condition in which the texture was most preferred, and 40%-80$^{\circ}C$ was the condition that yielded the highest color scores.

• Food Science and Preservation
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• v.21 no.5
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• pp.601-608
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• 2014

To determine the optimal shelf life for maintaining the high quality of kohlrabi, the changes in the physiological and secondary metabolites of kohlrabi stems during storage were investigated. The results showed that the kohlrabi maintained its marketable quality for two weeks at room temperature and for two months in cold storage ($4^{\circ}C$). Interestingly, the total phenol and flavonoid contents sharply declined along with the quality deterioration after two-week storage at room temperature. Moreover, insignificant changes in these compounds were observed for two months during the cold storage. The secondary metabolites of the kohlrabi were also influenced by its storage condition. The total phenol and total flavonoid contents of the kohlrabi significantly increased with the storage periods at low temperature, and significantly decreased with the storage periods at room temperature. In terms of the packaging, no significant difference in the total phenol content of the kohlrabi was found between the packaged and non-packaged types of storage. However, the flavonoid content of the packaged kohlrabi was higher than that of the non-packaged kohlrabi at the end of their storage. The content of glucosinolates, an anti-cancer ingredient was maintained during the storage, so the vegetables remained good sources of these compounds when stored in cold storage even for a long period. This study showed a close correlation between the secondary metabolites and the change in the quality of kohlrabi during storage. The results also suggested that secondary metabolites such as phenolics can be considered quality indicators of the shelf life of kohlrabi.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.9
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• pp.361-366
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• 2016

As an alternative of well-mixed storage tank with lower coil only, we have proposed a tank with lower and upper coils and verified a superior thermal stratification in a tank, which results in increased collector efficiency and solar fraction. But the phenomenon of temperature reversal was often experimentally observed in the tank, so a revised control was successfully applied which is to heat only lower coil using three way valve if temperature reversal occurs and to operate the collector with low flow rate when the condition of solar radiation is not good. In the present study, using TRNSYS we compared the existing lower heating and the proposed lower and upper heating with a control preventing temperature reversal. The results showed that the proposed method has an increase of collector efficiency by 5.1% and solar fraction by 3.2%.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.1
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• pp.67-80
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• 2021

We analyzed the effect of planting site (elevation: high, middle, low) and temperature condition of orchard on the frost injury occurrence and storage characteristics of persimmon (Diospyros kaki cv. 'Fuyu) fruits under an early fall frost at two orchards, Changwon (A) and Changnyeong (B), Gyeongsangnam-do Korea. Also, the fruits picked at Nov. 5 and Nov. 20 were MA stored to investigate the quality and chilling injury of fruits. On 2-way factor analysis, both planting elevation and orchard factor had not a significant effect on fruit characteristics (weight, firmness, soluble solid), while planting elevation factor did on the skin color (hunter 'a')(p<0.05). A fruit skin coloration at orchard A was faster than that at orchard B. At low elevation of orchard B, 2% fruits were frost injured at harvest season. On LDPE film MA storage with the fruits harvested at Nov. 5 and Nov. 20, the fruits at orchard A had higher fruit firmness than those of orchard B during storage. In addition, the 73% (orchard A) and 85%(orchard B) fruits harvested at Nov. 5 showed no chilling injury 80 days after storage. However, At harvest of Nov, 20 (after incidence of frost), only the 14% fruits of orchard B had no the chilling disorder 80 days after storage, even though 76% fruits at orchard A did.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.78-83
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• 2011

This study was conducted to evaluate germination rate of Vicia tetrasperma and V. hirsuta as affected by storage duration, temperature, and light. All seeds of both species were gathered from Dangjin, Chungnam in the late June of 2004 and 2005, stored for a certain period of time, and then exposed for 20 days to the alternating temperatures ($15/^{\circ}C,\;20/10^{\circ}C,\;25/15^{\circ}C$, and $30/20^{\circ}C$) for evaluating the germination rate. Both 2004 and 2005, two species stored at room temperature for 3 months had germination rates less then 30% with applying various alternating temperatures for 20 days although the highest germination rate was obtained with $25/15^{\circ}C$ treatment. V. tetrasperma at 12 month storage after seed gathering in 2005 had 82% of germination rate with $25/15^{\circ}C$ treatment and showed the increased rate as time passed. V. hirsuta at 6, 9, and 12 month storage after seed gathering in 2005 ranged, however, from 33 to 53% of the germination rate at alternating temperature treatments for 20 days and did not seem to be affected by the elapsed time of the storage. Storage at room temperature was more effective for increasing germination rate of both species compared to those of the storage at low temperature. The germination rate of both species was not significantly affected by either exposure of light or short period of high temperature.

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.20-25
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• 2008

This study was conducted to develop the industrial producing technology of sprout vegetables using the cut twigs of woody plants. We have cut the twigs of wild mulberry tree on 13 April,2006 to examine the sprouting rate as affected by the storage conditions on relative humidity of $40{\sim}50%$ and $80{\sim}90%$ under $4{\sim}6^{\circ}C$ temperature. And we have also investigated the sprouting growth following those storage period of twigs cut with $1{\sim}3$ buds. The longer storage periods, the less survival rate of wild mulberry twigs cut. The sprouting rate of cut twigs gathered on the day which had not stored at low temperature was 97.4%. And The sprouting rate at the relative humidity of $40{\sim}50%$ after storing at low temperature for 122 days were 34.2%, and that of at $80{\sim}90%$ relative humidity was 85.7%. The longer storage periods, the more the number, length and width of sprouts. Therefore, the twigs of a wild mulberry trees cut with $1{\sim}3$ buds were able to produce the sprout vegetables under the condition of temperature $4{\sim}6^{\circ}C$ and relative humidity $80{\sim}90%$.