• Food Science and Preservation
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• v.8 no.3
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• pp.279-285
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• 2001

The effect of chitosan and cacium treatment on the quality of satsuma mandarin(Citrus unshiu Marc. var. miyagawa) during storage were investigated. Citrus fruits treated with 2000-folds diluted iminoctadime-triacetate solution or 1.5% chitosan with 0.5% CaCl$_2$ solution were stored at 4$\^{C}$ and 87$\pm$3% relative humidity, and room temperature without humidity control. Decay ratio of chitosan and calcium treated fruits were lower than the ones with no treatment from the mid of February. Also, citrus fruits treated with chitosan and calcium treated less in weight loss, that seems it was derived from restraining of fruits' transpiration. Soluble solids were maintained higher level in chitosan and calcium treated fruits than with no treatment during the storage. Acid contents were decreased gradually lower in cold storage than in room temperature storage, and there was not showed consistent trend among treatments. 26 kinds of free amino acids among 45 standards such as glutamic acid, threonine, serine, alanine γ-amino buryric acid, aspragine and etc were detected in Citrus unshiu Marc. var. miyagawa. As the storage time was prolonged, free amino acid was disappeared more or less, and the deccreasing extent was less in 4$\^{C}$ than in room temperature storage.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.845-849
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• 1988

A laboratory scale storage facility consisting of a cold room, sample jars and a ventilation device was designed and built. Storaging sample jars (1.7 l) for fruit were fabricated with transparent acryl and provided with a constant air flow. For the supplying of air to sample jars, the air distributing system was built with solenoid valves, an air precooling coil and a pressure equalizing tank. To provide the programmable storaging environment of the facility a microprocessor-based controller was designed and installed. The controller was built with the 8 bit microprocessor (Z-80), EPROM, RAM, programmable peripheral interface(8255 PPI), and A/D converter. Softwares for the auto-temperature measurement and control of the storage system were developed and systemized in ROM. The automated storage system was applied to citrus storage, and the temperature of the storage facilities was successfully acquisited to the computer and controlled.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.666-672
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• 2014

The effect of nitric oxide (NO) treatment on the quality of kiwifruit, cv. Hayward, was studied at room temperature after cold storage for one or three months at $0^{\circ}C$. Kiwifruits cold-stored for one month were treated with $200{\mu}L{\cdot}L^{-1}$ NO and subsequently transferred to room temperature to monitor quality changes over the course of their shelf life. Weight loss was high in fruits not treated with NO. Ethylene production was delayed for two days by NO treatment, and respiration rate was reduced to less half than that of the control. The kiwifruits stored for three months were treated with $N_2$ and 100, 200, or $500{\mu}L{\cdot}L^{-1}$ NO, or air alone. The highest weight loss was observed in kiwifruit treated with $100{\mu}L{\cdot}L^{-1}$ NO. While ethylene production was high in fruits treated with $100{\mu}L{\cdot}L^{-1}$ NO and without the treatment, it was relatively low in the kiwifruit treated with 200 and $500{\mu}L{\cdot}L^{-1}$ NO. Firmness was abruptly decreased in fruits not treated with NO, while the kiwifruit exposed to $200{\mu}L{\cdot}L^{-1}$ NO maintained the s ame level of f irmness for 9 days a t room t emp erature. In addition, growth o f Botrytis cinerea was inhibited by NO as compared with the air and $N_2$ treatments. Our findings indicate that NO can be used effectively for prolonging shelf life and maintaining fruit quality during distribution after cold storage. The optimum NO concentration for cold-stored kiwifruits was found to be $200{\mu}L{\cdot}L^{-1}$.

• Journal of the Korean Society of Food Culture
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• v.33 no.2
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• pp.125-132
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• 2018

This study was carried out to determine the optimal storage conditions by examining the effects of the storage conditions on the quality of red pepper powder during storage in households. Red pepper powder was stored at room temperature ($20^{\circ}C$), refrigeration (2 and $-1^{\circ}C$) and frozen (-5 and $-20^{\circ}C$) for 3, 6, 9 and 12 months. The ASTA color value, capsanthin content and redness ($a^{\ast}$) of the red pepper powders stored at -5 and $-20^{\circ}C$ were not decreased significantly depending on the storage temperatures until 9 months. The pH of red pepper powder stored at $20^{\circ}C$ decreased significantly until 9 months and increased at 12 months. The microbiological quality of the red pepper powder stored at -5 and $-20^{\circ}C$ was more stable during long-term storage. In the sensory evaluation of red pepper powder stored under all conditions, the overall freshness, redness, hot flavor, moisture release, and edibility decreased with increasing storage period from the control to 12 months. Moisture release increased from 3 months to 12 months. Overall, red pepper should be stored at low temperatures (2, $-1^{\circ}C$) for up to 6 months, and frozen (${\geq} -5^{\circ}C$) for 6 to 9 months. The optimal temperature for long-term storage (${\geq}9$ months) was $-20^{\circ}C$.

• Progress in Superconductivity and Cryogenics
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• v.15 no.4
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• pp.6-9
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• 2013

Korea Superconducting Tokamak Advanced Research (KSTAR) has a helium refrigeration system (HRS) with the cooling capacity of 9 kW at 4.5 K. Main cold components are composed of 300 tons of superconducting (SC) magnets, main cryostat thermal shields, and SC current feeder system. The HRS comprises six gas storage tanks, a liquid nitrogen tank, the room temperature compression sector, the cold box (C/B), the 1st stage helium distribution box (DB#1), the PLC base local control system interconnected to central control tower and so on. Between HRS and cold components, there's another distribution box (DB#2) nearby the KSTAR device. The entire KSTAR device was constructed in 2007 and has been operated since 2008. This paper will present the maintenance result of the KSTAR HRS during the campaign and discuss the operation record and maintenance history of the KSTAR HRS.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.224-232
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• 2015

The effects of cold plasma (CP) treatments on the physicochemical and biodegradable properties of a corn biomass-containing polyester (CBPE) film were studied. The CBPE film was treated with CP generated by $N_2$, $O_2$, He, Ar, or dry air at 400-900 W and 667 Pa for 10-40 min. The glass transition temperature of the CBPE film ($-30.2--28.6^{\circ}C$) was not affected by the CP treatment, while the elastic modulus and water vapor permeability decreased (p<0.05). The ink printability was improved by the treatment and the improved printability was maintained during storage for 56 days at room temperature. Roughness of the film increased after treatments and the level of roughness appeared to increase during storage. Heat and microbial biodegradability of the CBPE film was improved by the air-CP treatment (p<0.05). These results have demonstrated the potential of applying CP treatments to improve the flexibility, printability, and biodegradability of CBPE films.

• 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.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.2
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• pp.119-128
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• 2023

This study was examined for investigating the quality changes of spring kimchi cabbage under various treatments (pre-drying/pre-cooling, packaging types, and stacking and loading in container and pallete in the storage room) during cold storage. The results showed that control (upward stacking without pre-drying/pre-cooling and HDPE or PVC film cover) was increased significantly in weight loss and trimming loss, compared to other treatments such as DPDH (downard stacking + pre-drying + HDPE), DPDP (downard stacking + pre-drying + PVC), DPCH (downnard stacking + pre-cooling + HDPE), and UPCH (upward stacking + pre-cooling +HDPE) during storage for three months. In Sensory evaluation, judging from marketable properties, the desirable appearance of spring kimchi cabbage with the modified pallet-unit MA packed, PE, and PVC film wrapping could be maintained until 9 weeks after pre-drying/pre-cooling. Meanwhile, the control without any treatments after 6 weeks, the sensory score was declined, significantly. In general, the low temperature (10℃ and 2℃) of pre-treatment with combination of plastic film packaging in spring kimchi cabbage storage could inhibit the physiological activity and reduce the direct exposure of environmental cold air in the storage. Therefore, these two variables were the key points for extending the shelf-life of spring kimchi cabbage.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.257-264
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• 2005

In order to establish the successive rearing system brush-footed butterflies (Lepidoptera : Nymphalidae) were reared in a room. Artificial diets were developed for a year-round rearing. Bu-diet was best to rear these butterflies among 3 kinds of diet used. The freeze-dried host plant leaf powder in diet was better than heat-dried one $(60^{\circ}C)$ in the growth of larvae. The rearing results were best in the diet C/N ratio was 1:1. The 24-hrs old eggs could be stored for 5 days at $15^{\circ}C$ or for 3 days at $5^{\circ}C$ and showed 75% of hatchability. On the other hand, pupae could be stored for maximum 15 days at $15^{\circ}C$ because the emergence of abnormal adults appeared much more as the cold storage period got longer. And the adult was able to be stored until 60 days at refrigerator without relation of nectar-sucking period before cold-storage and storage temperature. Also a simple artificial ovipositing kit was devised by ${\Phi}9$ cm of petri-dish and a female oviposited $278{\pm}27$ of eggs with adding the ether extract of host plant to this kit. The systematic successive rearing method of brush-footed butterflies in a room was completed.

• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.265-268
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• 2001

This experiment was conducted to investigate the effects of temperature, light, seed harvesting time, storage temperature, and period on its germination of Astragalus membranaceus. Optimum germination temperature was ${20{\sim}25^{\circ}C}$ and it was found to be light insensitive seed. The germination rates were not significantly different between 1-year and 2-year old plants, and seed harvesting times. Seeds stored at such cold temperatures as ${-4^{\circ}C\;and\;-20^{\circ}C}$ for 15 months showed over 80% in germination rate at the 6th day after placement. On the other hand, low germination rate of 60% at the 11th day was observed from the seeds stored at $4^{\circ}$ and room temperature.