• Journal of Biosystems Engineering
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• v.40 no.3
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• pp.261-270
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• 2015

Purpose: Cold storage is the most popular method used to preserve highly perishable foods such as beef and fish. However, at refrigeration temperatures, the shelf life of these foods is limited, and spoilage leads to massive food waste. Moreover, freezing significantly affects the food's properties. Ice crystallization and growth during freezing can cause irreversible textural damage to foods through volumetric expansion, moisture migration induced by osmotic pressure gradients, and concentration of solutes,which can lead to protein denaturation. Methods: Although freezing can preserve perishable foods for months, these disruptive changes decrease the consumer's perception of the food's quality. Therefore, the development and testing of new and improved cold storage technologies is a worthwhile pursuit. Results: The process of maintaining a food product in an unfrozen state below its equilibrium freezing temperature is known as supercooling. As supercooling has been shown to offer a considerable improvement over refrigeration for extending a perishable product's shelf life, implementation of supercooling in households and commercial refrigeration units would help diminish food waste. Conclusions: A commercially viable supercooling unit for all perishable food items is currently being developed and fabricated. Buildup of this technology will provide a meaningful improvement in the cold storage of perishable foods, and will have a significant impact on the refrigeration market as a whole.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1066-1075
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• 1996

To compare the efficacy of cardiac preservation, we examined purine metabolites during 24 hours of cold storage($0^{\circ}C$) of the Korean ongrel dog hearts after using three different types of cardioplegic solutions. The hypothermic arrest with total cardiopulmonAry bypass method was employed in 51. Thomas solution(575) and blood cardioplegic solution(BCPS) preservation cases. Specimens were analyzed for levels of adenine nucleotides and their precursors by high performance liquid chromatography. The ATP content in the UW(University of Wisconsin) solution group tends to be higher than that of the combined hypothermic arrest group(575 and BCPS groups) after 2,4,8, and 12 hours of preservation respectively, but there were no significant differences between 575 and BCPS groups. The ADP contents in the UWS and BCPS groups were higher than that of the 575 group at 4,8, 12, and 24 hours, but the difference was not statistically significant between UWS and BCPS groups. The AMP contents did not change significantly in the three groups. The adenosine, Inosine, and hypoxanthine concentrations increased progressively, but the lev l of xanthine was very low in the three groups.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.1
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• pp.16-18
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• 2002

During the process of freezing, spermatozoa suffer cold shock which increases their susceptibility to lipid peroxidation which plays an important role in ageing of spermatozoa, shortening their life span and affecting the preservation of semen. An experiment was therefore conducted to study the effect of addition of natural antioxidants into semen diluents on the preservability of buffalo semen. Split semen samples were extended in milk egg yolk diluents fortified with vitamin E (MYE), vitamin C (MYC) and control group (MYO); Tris-egg yolk diluents fortified with vitamin E (TYE), vitamin C (TYC) and control group (TYO) and evaluated for their preservabilities at 4-7$^{\circ}C$ and $37^{\circ}C$. Overall least squares mean of percent motility observed after 0, 24, 48, 72 and 96 h of preservation at 4-7$^{\circ}C$ were 66.70, 54.00, 36.80, 21.90 and 12.50, respectively while the estimates for semen extended in MYE, MYC, MYO, TYE, TYC and TYO were 44.80, 42.70, 38.70, 36.00, 35.20 and 33.00 percent, respectively. The results showed that motility was significantly (p<0.01) affected by extender (extender-antioxidant combination) and preservation interval. Overall least squares mean percent motility observed after 0, 4, 8, 12 and 24 h of preservation at $37^{\circ}C$ were 68.50, 58.90, 45.00, 38.10 and 18.10 percent, respectively, while the estimates for semen extended in MYE, MYC, MYO, TYE, TYC and TYO were 48.20, 49.30, 46.80, 45.30, 42.30 and 42.50 percent, respectively. Extender and storage interval were found to be significantly (p<0.01) affecting spermatozoa motility on room temperature preservation. The results indicated that the incorporation of antioxidants, especially vitamin E, had beneficial effect on preservability of buffalo semen.

• Restorative Dentistry and Endodontics
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• v.31 no.3
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• pp.192-202
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• 2006

The purpose of this study was to examine the viability of PDL cells in rat molars by using in vivo MTT assay, which was used to compare fast cryopreservation group by liquid nitrogen $(-196^{\circ}C)\;with\;4^{\circ}C$ cold preservation group. A total of 74 Sprague-Dawley white female rats of 4 week-old with a body weight of 100 grams were used. The maxillary left and right, first and second molars were extracted as atraumatically as possible under ketamine anesthesia. Ten teeth of each group were divided as six experimental groups depending upon the preservation. Cryopreservation groups were Group 1 (5% DMSO 6% HES in F medium) Group 2 (10% DMSO in F medium), Group 3 (5% DMSO 6% HES in $Viaspan^(R)$). Group 4 (10% DMSO in $Viaspan^(R)$) which were cryopreserved for 1 week and cold preservation groups were Group 5 (F medium) , Group 6 ($Viaspan^(R)$) at $4^{\circ}C$ for 1 week. Immediate extraction group was used as a control. After preservation and thawing, the in vivo MTT assay was processed. Two way ANOVA and Duncan's Multiple Range Test was performed at the 95 % level of confidence, Another 2 teeth of each group were treated as the same manner and frozen sections $10{\mu}m$ thick for microscopic observation. The value of optical density obtained after in vivo MTT analysis was divided by the value of eosin staining for tissue volume standardization. Group 1, 2 had significantly higher optical density than Group 3 and 4 which had the lowest OD value. Group 6 had higher OD value than in Group 5 (P<0.05). Histological findings of periodontal ligament cell, after being stained with MTT solution were consistent with the in vivo MTT assay results. In this study, the groups which were frozen with DMSO as a cryoprotectant and the groups with F medium showed the best results.

• Food Science and Preservation
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• v.10 no.1
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• pp.1-5
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• 2003

This study was carried out to extend a marketing shelf-life of the Jeju greenhouse mandarin fruits. Total soluble solids were not showed any significant differences by the temperatures and pre-treatments during the marketing period. Acid content and firmness of the fruits were gradually decreased, which were better in cold than in room temperature treatment. The fruits washed in electrolyzed acid water(pH 2.4∼2.7) maintained freshness higher than those of control Internal CO$_2$concentration of those was 1.0 ％ more or less in the beginning marketing stage, but increased along the marketing period in mom temperature. Especially Internal CO$_2$concentration of wax-coated fruits rapidly increased more than any other, whereas it was a little decreased in cold treatment. After 10 days in room temperature, decay ratio of the fruits was below 4.0% in electrolyzed acid water washing, compared to 10.4% in control. After 30 days in cold temperature, decay ratio was only 3.7% in electrolyzed acid water washing compared to 4.4% of wax-coated treatment and 7.4% of control. The weight loss among the pre-treatments in room temperature had no significant differences and was higher than in cold one.

• Food Science and Preservation
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• v.10 no.1
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• pp.28-31
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• 2003

For safe storage of agricultural products in the cold storage house, accurate monitoring of temperature, humidity and gas conditions is necessary. This study was conducted to develop an environmental monitoring and warning system for the cold storage house to improve safety of storage. The system developed in this study is able to monitor temperature, humidity and $CO_2$concentration in the storage house and to send alarm signal to the farmer by telephone and beeper when abnormal conditions have been occurred in the storage house. And the developed system use internet network so we can supervise storage conditions in the home. From the results of the performance test, it was found that the temperature and relative humidity can be controlled within the range of 0.5$^{\circ}C$ and $\pm$2 percent. And farmer's response was fair.

• Food Science and Preservation
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• v.24 no.8
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• pp.1088-1093
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• 2017

This study was conducted to investigate the effects of drying methods for Citrus junos peels on quality characteristics of the hot-water leachate from teabags containing those peels. Fresh peels were hot-air ($50^{\circ}C$), cold-air ($30^{\circ}C$), or freeze-dried ($-45^{\circ}C$), powdered to a size of 40 mesh, packaged with a paper sachet, and then the packaged teabags were leached for 10 min with hot-water ($70^{\circ}C$). $L^*$ value (lightness) and $-a^*$ value (greenness) of the peel powder were the highest in the freeze-dried samples. Soluble solids and titratable acidity of the teabag leachate were in the following order; cold-air, freeze, and hot-air dried samples. Among free sugar contents in all samples, fructose content was the highest, followed by glucose and sucrose. Fructose and glucose contents were not affected by drying methods. There was no significant difference in the flavonoid content among the peels dried using three drying methods. DPPH radical-scavenging activity of the leachate was the highest in the cold-air dried sample. These results suggest that cold-air drying would be an effective method to enhance the quality of hot-water leachate of teabags prepared from C. junos peels.

• Food Science and Preservation
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• v.13 no.1
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• pp.37-42
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• 2006

In recent, Kimchi is produced in the scale of industry, Consumers show increased demand of safety and high quality and hygienic process control. So, sun drying, hot air drying and cold air drying methods were investigated to compare the demand Sun drying took 96 hrs, hot air drying took 4 hrs at $70^{\circ}$ and cold air drying took 102 hrs at $10^{\circ}C$ in removing water to $90\%$ from radish. Brownness of radish was expressed as absorbance. Absorbance were 0.20, 2.04 and 1.87 and also Vit-C contents were 0.14 mg/g, 0.12 mg/g and 0.096 mg/g in dried radish according to cold air drying, hot air drying and sun drying, respectively. From overall experimental results, cold air drying method was found as superior drying method to other drying methods.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.35-37
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• 1986

To reduce the number of rearing season required for preservation of multivoltine silkworms which do not produce diapause eggs, the optimal egg stage, temperature, and period of cold storage were examinede using hatchability as an indicator of viability. Multivoltine silkworm starains MR, SPT, and HM were used in the study. 1. The hatchability of multivoltine silkworm eggs (MR and STP) preserve at 5$^{\circ}C$ for 30 days was 80% for the eggs chilled from 2 days after oviposition but less 5% for those chilled from 7 days after ovipostion. 2. When 2 day-old eggs of multivoltine silkworm (HM) were preserved between -2.5$^{\circ}C$ to 7.5$^{\circ}C$ for 15 to 60 days, $0^{\circ}C$ and 2.5$^{\circ}C$ showed the highest hatchability with 91% at 30 days and 61% at 60 days storage, respectively. 3. From these results, it can be concluded that by preserving 2 day-old eggs at 2.5$^{\circ}C$ for 50 to 60 days, rearing seasons required for preservation of the multivoltine silkworm can be reduced to half per year.

• Food Science and Preservation
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• v.10 no.4
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• pp.466-469
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• 2003

To develope corrugated paperboard box for cold chain system, it was investigated to compression strength and size of air hole. The size of air holes of the side tested box were designed as six groups, 4, 7, 10% and two kind of air hole, 2, 3 hole per the side. Compression strength of box(440${\times}$330${\times}$170 mm(length${\times}$width${\times}$height))was tested by compression tester UM-20Y, DaeSin Co., Korea, speed is 12.5 mm/min), it was stored 4 week at room temperature, RH 70${\times}$5%. Compression strength was high the mort narrow, the longer of air hole. Compression strength of box of the side, 4% was 10% higher among 4, 7, 10%, but differentiate of compression strength owing to the number of air hole was below 10%. for improving the compression strength of box, paper board box for cold chain system was made of the narrow of width and of the long length of air hole.