• Journal of Life Science
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• v.14 no.4
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• pp.664-669
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• 2004

The contamination of Bacillus cereus was investigated in 240 RTE (ready-to-eat) food samples including 118 seafoods, 82 Korean packaged meals and 40 other RTE foods. Many B. cereus presumptive strains were isolated from the enrichment culture in Tryptic Soy Broth (TSB) added polymyxin, followed by selective culture in Mannitol Egg Yolk Polymyxin (MYP) agar and Gram staining. A total of 36 strains (16 in seafoods, 17 in Korean pack-aged meals and 3 in other RTE foods) were identified as B. cereus by the analysis of 61 biochemical tests of the API 50CHB/20E system test and supplementary tests of $\beta$-hemolysis, rhizoid growth, motility and oxidase activity. The 28 strains out of 36 B. cereus isolates produced diarrhoeal enter-otoxin in Brain Heart Infusion (BHI) broth. All isolates were resistant to ampicillin and penicillin antibiotics, and most of them were susceptible to gentamicin, vancomycin, bacitracin, chloram-phenicol, kanamycin and streptomycin. The growth of B. cereus was affected by environmental temperature and incubation time. Culture with temperature under 1$0^{\circ}C$ effectively restricted the growth of B. cereus.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.426-431
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• 2011

In this study, we set an optimum blanching condition as a pretreatment condition to freeze welsh onion (Allium fistulosum L.) for the purpose of preserving the cooking material for long-term usage. With higher blanching temperature and longer processing time, the Hunter color values and the hardness of welsh onion tended to decrease, which confirmed softening of the tissue. Compared to before blanching, total bacterial counts decreased to near 2 log scale, whereas coliforms were not detected or decreased to a 1-2 log scale. Blanching by heating at 100$^{\circ}C$ for 5 min decreased peroxidase inactivity to more than 94%, whereas only 47% of the inactivity was achieved at 80$^{\circ}C$ for 1 min. The sensory evaluation for the blanched and defrosted welsh onion showed that the group blanched at 80$^{\circ}C$ for 1 min was preferred significantly (p<0.05).

• Horticultural Science & Technology
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• v.28 no.5
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• pp.902-911
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• 2010

Oriental melon ($Cucumis$ $melo$ var. $makuwa$) is a popular and high-value market fruit cultivated in Korea. Consumers are becoming increasingly interested in oriental melon as a healthy diet over the past few years. However, the melons have relatively high quality loss because the fruit are mainly produced for a limited period of time in the summer season. Lack of the proper postharvest treatments and high temperature exposure at harvest or during distribution are the most critical environmental factors limiting postharvest life of fruit. This review focuses on the overview of current research studies for postharvest treatment and functional packaging technology of oriental melon in Korea. Major physiological problems of the harvest fruit include the ripening process in quality changes of the produce such as loss of weight, firmness, flavor, and decay during the storage periods. Low temperature at 7 to $10^{\circ}C$ with high relative humidity of 90 to 95% is the suitable environmental condition used to maintain the quality of fresh oriental melon. Controlled atmosphere (CA) storage or modified atmosphere (MA) packaging can be used as supplemental treatments to extend postharvest-life. For oriental melon, an optimum CA is currently recommended to be 2-3% oxygen and 5-10% carbon dioxide atmosphere. Precooling, pretreatments of ethylene action and functional packaging system can be applied to oriental melon after harvest in order to extend storage life. Major active packaging technologies are concerned with a selectively gas permeable film related to respiration of produce and the packaging applications of ethylene removal, antimicrobial, and antifogging substances to keep the effective freshness of fruit.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1095-1103
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• 2014

A packaging and distribution system for transferring individual live squids at low temperature was developed and compared to a conventional bulk container system. Ten live squids in individual packages were stored in a large container at low temperature ($0{\sim}10^{\circ}C$). Live squids in individual packages at $6^{\circ}C$ showed a survival rate of 84% up to 72 hours, after which the survival rate decreased. However, the survival rate remained at 60% up to 120 hours. Further, the squids survived up to a maximum of 7 days. Optimum temperature was $5^{\circ}C$, and the survival rate of the packages was 70% when stored at $5^{\circ}C$ for 96 hours. A distribution test was carried out using a refrigerator truck at $5^{\circ}C$, and the results showed a 100% survival rate up to 16 hours and over 90% survival rate after 20 hours. A rectangular container was the most favorable when loading the container into the refrigerator truck. In testing the required volume of supplied seawater, 100% survival rate was observed over 15 hours with 20 L of sea water or more. Therefore, a single squid needed 2 L of seawater. After refrigerator truck transportation, optimum temperature for fish tank storage was $5^{\circ}C$, at which the survival rate was over 90% up to 72 hours. Using a refrigerator truck at $5^{\circ}C$, live squids survived up to 7 days, maintaining marketability.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.40-45
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• 2001

This study was conducted to investigate the effects of various emulsifiers on the quality of the waxy rice cake. Falling numbers of the waxy rice flour with monoglyceride, lecithin and control were not significantly different, but with sugar esther 0.5% and 1% showed higher value as 88.4 and 81 than control Initial pasting temperature of the waxy rice flour was 66.78$\^{C}$ and others were 66.45 ∼ 67.05$\^{C}$ by adding 0.5%, 1% of emulsifiers such as monoglyceride, lecithin, sugar esther. Waxy rice flour with 1% sugar ester showed the highest peak viscosity as like as falling number. Waxy rice cake wish various emulsifiers showed tendency to be slowly firming rate as compared with control. In all case, waxy rice flour with sugar ester 1% was considered to be more effective to the decrease of firming rate. Waxy rice flour with lecithin showed worse visual color than others and sugar ester provided best visual and sensory quality. After 5 days cold storage, waxy rice flour with sugar ester 1%\`s Aw was 0.875 and control\`s 0.911. These results suggested that water holding capacity of sugar ester was the best during storage.

• Journal of Conservation Science
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• v.28 no.1
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• pp.21-27
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• 2012

In the Chosun period, the noble class usually buried the dead bodies in the lime-covered tomb. Recently their costumes are excavated while maintaining the shape. However, the textiles discovered from the inside have been degradated by a body and moisture. To conserve these textiles one of the most important thing is how to clean these textiles right after the excavation. The purpose of this study is to examine the effects of wet cleaning to minimize the color change of textile remains. For this purpose, silk and cotton were dyed with natural dyes (7 red, 1 blue, 6 yellow, 4 green and 4 purple colors), then they were kept for 6 months with pork meat at $10^{\circ}C$, and were washed by four cleaning solutions (water, anionic surfactant (SDS), non-ionic surfactant (Triton X-100) and natural surfactant (saponin)) at $20^{\circ}C$ and $40^{\circ}C$. The color change was evaluated by color difference (${\Delta}E$) between non-treated and after washed samples. From the results, it was found that the color changes are significantly different depending on the washing temperature, textile material, the cleaning agents and the type of dyes.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.409-416
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• 2007

This study investigated changes in the catechin and alkaloid contents of Bosung green tea during different manufacturing processes and storage periods, using HPLC and UV-VIS spectrophotometer analysis. For changes in the catechin and alkaloid contents by roasting technique, we found that EGCG, CG and GCG decreased just slightly by processes performed before roasting, rather than after roasting. In addition, theobromine, caffeine, and ECG changed minimally throughout all the processes. For changes in the catechin and purine alkaloid contents of the green tea leaves during storage, EGCG, ECG, and CAF decreased considerably in the green tea stored at temperatures of $5^{\circ}C$ and $25^{\circ}C$, and they decreased by $20{\sim}30%$ after storage for 1 year. However, a quantitative difference was hardly observed in the catechin and alkaloid contents regardless of storage temperature.

• Food Science and Preservation
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• v.14 no.3
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• pp.239-246
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• 2007

The effects of gamma irradiation on the physiochemical and physical characteristics of apples were investigated during post-irradiation storage at $4^{\circ}C\;and\;25^{\circ}C$. The contents of total and reducing sugars were analyzed and the results indicated that apples receiving 1 kGy of gamma irradiation did not show significant differences in sugar contents compared to non-irradiated controls. Important physiological characteristics were evaluated by measurement of total phenolic content and total flavonoid content, reducing power, and radical scavenging ability, and the results indicated that gamma irradiation at a dose of 1 kGy did not affect physiological activities. Changes in physical parameters such as weight loss, strength, cohesiveness and hardness, during post-irradiation storage, were temperature-dependent, whether the apples were irradiated or not The color and sensory acceptance of the apples were not affected by irradiation during cold storage. However, minor deterioration in color quality and sensory acceptance of irradiated apples was noted under ambient temperature storage. We conclude that gamma irradiation(1 kGy) does not affect apple nutritional content stability, functional properties, or physical characteristics, especially upon cold storage after radiation treatment.

• Food Engineering Progress
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• v.15 no.3
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• pp.230-234
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• 2011

The objective of this study was to optimize the thermal condition and determine the shelf life of heated Chunbokjang product. The optimum thermal condition of heated Chunbok-jang product was determined by sensory test, and heat penetration curve was obtained by Thermal Microprocessor. Sterilization time was a 21~23 min until $F_0$ value reached 9 min, depending upon the number of abalone. As solid content was reduced and temperature of sterilization was increased, the thermal death time was decreased. The score of sensory test indicated that there was no significant difference in flavor of heated Chunbok-jang product made at different sterilization temperatures (110, 121.1, 125, and $130^{\circ}C$). Heated Chunbok-jang product, however, sterilized at $125^{\circ}C$ showed the highest score in texture and taste values. Salinity and pH were not changed during seven month storages, but texture became firmer, and any microorganism had not been detected from the heated chunbok-jang product during these periods. As a result of storage experiment, the shelf-life of heated Chunbok-jang product was 3-month at room temperature.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.94-102
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• 2020

Renewable energy (RE) is essential to comprise sustainable societies, especially, in rural villages of developing countries. Furthermore, application of off-grid RE systems to health care can improve the quality of life. In this research, a RE-based vaccination supply management system was constructed to enlarge the cold-chain in developing countries for the safe storage and delivery of vaccines. The system was comprised of the construction of RE plants and development of vaccine carriers. RE plants were constructed and connected to health posts in local villages. The cooling mechanism of vaccine carriers was improved and monitoring devices were installed. The effect of the system on vaccine cold-chain was evaluated from the field test and topographical analysis in the southern village of Nepal. RE plants were normally operated for the vaccine refrigerator in the health post. The modified vaccine carriers had a longer operation time and better temperature control via monitoring and RE-based recharging functionality. The topographical analysis estimated that the system can cover larger region. The system prototype showed great potential regarding the possibility of a sustainable and enlarged cold-chain. Thus, RE-based vaccine supply management is expected to facilitate vaccine availability while minimizing waste in the supply chain.