• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.252-255
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• 1988

The molding characteristics, hardness and overall quality of the Korean style disposible food tray made from the low and medium density polystyene sheets were investigated and the results were obtained as follows. The volume difference of 8 sectional trays was 56.4% between the two materials, and that of 5 sectional trays was 41.8%. The more the sectional number of the tray, the larger the volume difference. Medium density polystylene tray had the better solid characteristics and overall acceptance than the low density polystlene tray.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.187-195
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• 2021

In order to assess the cell toxicity of 10 instruments made of polymers, the MTT assay which utilizes the L-929 cell was selected. Specimens were eluted at a temperature of 37℃ for 24 hours at a rate of 4g per 20mL, RPMI 1640, and then was positively and negatively contrasted with a control test solution, in accordance with the Notification No. 2020-12 Protocols of Medical Apparatus Biological Safety from the Ministry of Drug and Food Safety. As a result of 24 hours of incubation in 37℃, 5% CO₂ Incubator and assessment using an ELISA reader, the results of Intraoral camera indiciated a cellular viability of more than 70% at a 50% eluate. But, the Plastic impression tray, 3D printing tweezer, Impression disposable syringe, Dental floss holder, Hand implant scaler, Surgical retractor, Oral scanner tip, Dental mirror, and the Water pick tip all reported a cellular viability of more than 70% at a 100% eluate, which indicates that do not exhibit cytotoxicity, thus allowing it to be used in contact with the mucous membrane of the oral cavity.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.593-605
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• 2004

An egg has been considered as one of the most important food sources because of it's nutritional superiority and reasonable price. With the complexity of egg flow system from production to consumption in Korea, preventive measures for egg safety have been required. Therefore, our study was carried out to analyze hazards for the egg under farm level and develope preventive measures with a purpose of obtaining egg safety. To analyze biological hazards, microbial contamination of egg(normal, dirty and cracked), water, feed, manure and equipments associated with laying were investigated. One isolate of Salmonella enteritidis and S. bardo were detected from the manure and dirty egg shell respectively. The sanitary conditions in the farm were surveyed by questionaries. Confirmation of vaccination for purchasing chicks and establishment of sanitary guidances for water and type of water suppliers ought to be preceded. Feed supplier systems including feed tanks, feed pipes and hoppers were known that their contamination might give it a chance to infect individuals and egg content and shell. The safe and rapid disposal of dead chickens and rodent were reported as more crucial factors to prevent infectious disease and manage good sanitation. Egg selector and collecting belt should be kept properly not to be contaminated from egg fluids and feces. It should be also considered that regular gathering of eggs, removal of dirty or cracked ones, storage under refrigeration and the use of disposable egg tray were continuously fulfilled. Conclusively, Our results suggested that HACCP-based system for providing fresh and safe eggs to consumers should be applied to the farm.