• Food Science of Animal Resources
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• v.43 no.6
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• pp.1170-1182
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• 2023

The aim of this study was to determine the effect of chitosan (CH)-based nanocomposite coating applications [chitosan+TiO₂ (CHT) and chitosan+TiO₂+rosmarinic acid (CHTRA)] on changes in quality attributes of rainbow trout fillets during cold storage (4℃). Fish fillets were randomly divided into four groups and subjected to treatments (CH, CHT, CHTRA, and control). After treatments, the groups were packaged under a modified atmosphere (40% CO₂+30% O₂+30% N₂) and stored at 4℃ for 18 days. During cold storage, the samples were subjected to physico-chemical and microbiological analyses. During storage, CH, CHT, and CHTRA treatments showed lower aerobic mesophilic and psychrotrophic bacteria counts than the control. However, the differences between coating treatments were not significant. The highest mean pH value was determined in the control group. As the storage time increased, the thiobarbituric acid reactive substances value increased. At the end of the storage period, no significant differences were observed between the treatments, including in the control group. The total volatile basic nitrogen (TVB-N) level in the control group was above 25 mg/100 g on day 15 of storage. However, the TVB-N level in the treatment groups was below 20 mg/100 g on day 18. It was also determined that coating application×storage period interaction had a significant effect on all color parameters (p<0.01). At the end of storage, the highest CIE L* was observed in CHTRA treatment. However, the value of this treatment did not differ from that of the CH treatment.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.106-113
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• 2009

Germination percentage of Korean native lily seeds was high at $20-25^{\circ}C$. It was almost 100% in L. cernuum, L. callosum, L. amabile, and L. concolor, 88.0% in L. lancifolium, and 73.0% in L. maximowitzii, respectively. Meanwhile, it was low rate of 34.0%-54.0% in L. distichum, L. hansonii, and L. tsingtauense. Germination was mostly delayed of $15^{\circ}C$ and days to germination were more shortened in species with higher germination percentage. Even though the effect of daylength was not considerable in germination rate, it was promoted in L. maximowitzii but it was delyed in L. hansonii under long day. The effect of soaking in hot PGRs solution in L. callosum, L. cernuum, L. amabile, L. lancifolium, and L. concolor did not show any difference in comparison with non-treatment. However, it was improved by BA in L. maximowitzii. Longer period of cold wet storage resulted in improved germination percentage in L. maximowitzii and L. lancifolium, while it affected decreased percentage in L. distichum and L. hansonii. Days to germination were shortened by longer period of cold wet storage regardless of species. Germination percentage in dry storage was higher under cold temperature than room temperature and under desiccator storage than outside desiccator, it was highest under desiccator storage at $4^{\circ}C$. It was drastically reduced by the non-use desiccator storage at room temperature L. concolor, however it was improved only by the use of desiccator L. maximowitzii for a long time.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10a
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• pp.9-18
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• 2003

A method for rapid propagation of mature Jack fruit was developed. Four types of explants (mature embryos, apical meristems of young seedlings, apices from mature plants and nodal segments) were used. It has been found 88% of young apical meristems produced shoots in Campbell and Durzan (CD) medium compared to 60% in Murashige and Skoog (MS) medium. Only 1/3 of them produced multiple shoots. Shoot idtiation from nodal segments was very rare. Mature apices produced callus. Although removed of the sheathing cover around mature buds enhanced the shoot initiation but success rate was low in growth regulator free medium. Embryos respond to the CD medium but not to the MS medium. Embryos from seeds soaked in water for 24 hours produced shoots after 8 weeks of incubation and the success rate was 70% while embryos from dry seeds only produced roots. There was no significant effect of cold storage (refrigeration) for 7 days on shoot initiation from mature embryos (65%) but the ability for shoot induction declines with storage time (55% after 21 days of cold storage). Mature axillary buds were established in Modified Campbell and Durzan (CD) medium supplemented with 0.5mg/1 and IBA. There was a significant difference in the growth performance of shoots according to the period of the year in which explants were collected. Highest (60%) was observed in November-January period. It was only 30% when the explants were collected in February-April or May-July and decreased to 20% in August-October. The shoots produced in November-January showed a higher vigor than those produced in other months. Since Jak fruit show seasonal changes in fruit bearing and shedding of leaves, it can be suggested that the difference in growth performances of tissues cultured in artificial culture media would have been affected by endogenous rhythms.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.9-15
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• 1997

This experiment was carried out to investigate the effects on shelf-life of chilling and packing methods of cold chicken breast and thigh meats. Deboned chicken breast and thigh meats were packed by either vacuum or atmosphere packing method, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The thiobarbituric acid(TBA) values of all treatments were significantly increased as the storage period extended(P<0.05), however, TBA values of all treatments were remark-ably decreased at 15 days. TBA values of immersion chilled and vacuum-packed thigh meats were increased, but no difference between atmosphere and vacuum-packing methods was found. The volatile basic nitrogen(VBN) values at 1 day of storage were low, but they were increased as the storage period extended. The VBN values at 20 days after storage were from 12.25~19.28 mg %. Total bacterial counts tended to increase in all treatments, however, no significant difference was found in any treatment. Total plate counts of breast meat were higher than those of thigh meat as the storage period extended.

• Korean Journal of Food Science and Technology
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• v.7 no.3
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• pp.128-134
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• 1975

For development of long-term storage method of sweet-persimmons using polyethylene film bags, basic experiment was conducted with 30 boxes of sweet-persimmons in 1973 and the same experiment was extended for industrial application with 2,500 boxes of the persimmons in the cold storage of Jinyoung Sweet-persimmon Association in 1974. Investigation was made on change of the quality by storage period. At the same time, persimmons put in the cold storage test were shipped to market at different time in order to monitor consumer response and commercial feasibility. The followings are conclusion obtained from the result of this experiment. 1. Storage of sweet-persimmon, Buyu, produced in Jinyoung, Kimhae was possible for 1 month at $2^{\circ}C{\pm}1^{\circ}C$ cold storage. This storage period was extended to 4 months until the end of February in case that the fruits were hermetically sealed in P.E. film bags of 0.08 to 0.1 mm thickness. 2. During the storage period of sweet-persimmons packed in the film bags, the loss of weight due to evaporation was effectively prevented with use of the film of bag thicker than 0.04 mm. 3. The storage ability of 3-5 persimmons per small bag was somewhat superior to that of many persimmons packed in the large box of 15kg capacity. 4. The thicker the film of bags, the more $CO_2$ gas was accumulated inside, however, from 1 month after beginning of the storage the rate of $CO_2$ accumulation became very low maintaining the stabilized level of 5-6% at the plot of 0.06-0.08mm thick bags. 5. While the persimmons were in storage, decreased was the content of total sugars, total acids, and vitamin C, of which the phenomenon was remarkable especially with the fruits of non-packed plot. 6. The sweet-persimmons in the film bags subjected to cold storage when shipped to market in their intact condition were more beneficial than when they were shipped out in unpacked condition. The intact fruits packed in the P.E. film bags were able to keep their commercial value for 10days in the outdoor situation. 7. The sweet-persimmons that were packed in the film bags and put in the cold storage had maintained promissing marketability and the economic feasibility was acknowledged when the experimental practice was applied to industrial scale.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.3
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• pp.277-284
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• 2001

One of the problems in a refrigerator operation is the frost formation on a cold surface of the evaporator. The frost layer is formed by the sublimation of water vapor when the surface temperature is below the freezing point. This frost layer is usually porous and formed on the cold surface of the evaporator. The frost layer on the surface of a evaporator will make side effect such as thermal resistance. However, these important factors have not been used in determining the defrosting period. Therefore, the proper defrosting operation period based on the new defrosting method is very important, and make a comparison between conventional method like electric defrost and new method in compression work, evaporation pressure, evaporation temperature.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.257-268
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• 2016

Physiological characteristics of five new apple cultivars from the Korean apple breeding program were evaluated as a function of harvest time and storage after harvest. Internal ethylene concentration (IEC), flesh firmness, soluble solids concentration (SSC), and titratable acidity (TA) were measured in 'Summer Dream', 'Summer King', 'Green Ball', 'Picnic', and 'Hwangok' apples at harvest, during shelf life at $20^{\circ}C$, and one day after cold storage at $0.5^{\circ}C$ in air. IEC increased during shelf life in 'Summer Dream', 'Summer King', and 'Green Ball' but not in 'Picnic' or 'Hwangok', regardless of harvest time. Flesh firmness decreased towards harvest time and decreased gradually with time in cold storage only in the former three cultivars. In turn, IEC increased during cold storage in the first three cultivars but not for the last two cultivars, irrespective of harvest time. Changes in SSC and TA did not consistently relate to harvest time or storage period but TA tended to decrease as IEC increased. Furthermore, IEC was negatively correlated with flesh firmness except in the 'Green Ball' cultivar but the significance level was much greater in 'Summer Dream' and 'Summer King' (p < 0.0001) than in 'Picnic' (p < 0.01) or 'Hwangok' (p < 0.05) cultivars. Flesh firmness was positively correlated with TA in the first three cultivars but not in the last two cultivars. Overall, the results indicate that cultivars for which IEC increased after harvest had reduced flesh firmness and TA after storage.

• The Korean Fashion and Textile Research Journal
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• v.12 no.4
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• pp.513-522
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• 2010

The aim of this study is to investigate the actual state for the development of the thermally comfortable uniform for workers on a low temperature storage. Observation, interview and survey were executed focusing on the environment, clothing, and human factors which have effects on the comfort of workers. Of 400 distributed, 253 questionnaires were analyzed through descriptives, frequency, ANOVA, t-test, multi-response analysis, correlation analysis with SPSS 12.0. The results are following. Coming and going between a selling area and cold storages, the workers showed to experience a big temperature gap. They indicated to feel cold on face and hands which were not covered by clothing and have got sick because of low temperature. The workers wanted the uniform made of functional fabrics, especially heat insulation fabrics. Female workers rather than male workers, the older, and the longer their working period were, the more uncomfortable they revealed to feel. The workers who works on the daily products part or mainly on the freezer appeared to feel cold more than any other workers. In conclusion, it was found that the uniform which consider steady state and unsteady state heat transfer together must be developed.

• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.2
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• pp.51-57
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• 2014

Bumblebees are important pollinators of crops and wildflowers. The Korean native bumblebee, Bombus ignitus, undergoes one generation per year, and induction of artificial hibernation is essential for year-round rearing of the bumblebee. Keeping queens under cold treatment conditions for several mo is an effective method for terminating their diapause and promoting colony development. In the present study, we investigated how the timing and duration of chilling affect the artificial hibernation of B. ignitus queens. In the timing assessment, cold treatment was instituted at 12 d, 40 d, or 100 d after eclosion under a constant temperature of $5^{\circ}C$ and 80% humidity. The queens that entered cold treatment at 12 d after emergence evidenced the highest survival rates: 86.7% at two mo, 73.3% at three mo, and 46.4% at 4 mo. Survival rates were reduced under storage conditions at 12 d, 40 d, and 100 d after emergence. When queens were subjected to chilling at 8 d, 12 d, or 16 d after eclosion with constant 80% humidity, the queens stored at 12 d after eclosion exhibited the highest survival rates, which were 84.6 at one mo, 25.0% at two mo, and 7.9% at three mo. In regards to the duration of the cold period, the queens that hibernated for at least two mo evidenced optimal colony development rates. The rates of oviposition, colony foundation, and progeny-queen production of queens hibernated for two mo were 60.0%, 30.0%, and 13.3%, respectively. These values were 6.0 to 13.3 times higher than those in the queens that hibernated for 15 d. Therefore, a cold period of at least 2 mo applied 12 d after emergence were found to be the most favorable conditions for diapause break in B. ignitus queens.

• The Journal of Korean Medicine
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• v.30 no.2
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• pp.127-132
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• 2009

Objectives: This study aimed to investigate the stability of a decoction using three herbal plants and their major components according to the storage conditions and periods. Materials and Methods: A three-herb mixture (1:1:1) of Glycyrrhiza uralensis Fischer, Artemisia capillaris Thunberg, and Poncirus trifoliata Rafinesqui was decocted and kept at room temperature ($25{\pm}2^{\circ}C$) or cold temperature ($4^{\circ}C$) for 0, 2, 4 or 8 weeks in liquid form in a plastic pack under dark conditions. At time points given, they were lyophilized. 200 mg of powdered samples were dissolved in 1 mL of 90% methanol and then applied to a high performance thin layer chromatography (HPTLC) with glycyrrhizin, 6,7-dimethoxycoumarin or poncirin for quantitative or qualitative analysis. Results: There were no gross changes in HPTLC-based compositional band-patterns of the three herbal mixture according to the storage conditions and period. The major components of each herb, glycyrrhizin, 6,7-dimethoxycoumarin and poncirin, showed slight time-dependent reduction in their contents both at room and cold temperature for 8 weeks. Conclusion: We could conclude that the current herbal decoction is generally safe for the stability at both RT or CT for at least 8 weeks. Nevertheless, we proposed that further advanced studies are required for more multiple herbal mixtures and longer storage periods.