• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.14 no.2
• /
• pp.57-63
• /
• 2008

The effects of airtight containers and zipper bags on the freshness extension of pine nuts (Pinus koraiensis) were studied at 4 and $25^{\circ}C$. Changes in total microbial growth, 2-thiobarbituric acid(TBA), color, and sensory quality were evaluated during storage. Total bacterial counts of the samples continuously increased over 28 days for airtight containers and 56 days for zipper bags, and then decreased at 70 days because the lack of air could affect the inhibition of the aerobic microbial growth. However no significant differences were observed between airtight containers and zipper bags. TBA values continuously increased with storage time, but there were no significant differences between the airtight containers and zipper bags during storage. Color changes and sensory evaluation analyses showed that the data revealed similar results for both packaging systems over the storage time. Therefore, it has been concluded that airtight containers and zipper bags could be used as a good packaging system to extend the shelf life of pine nuts by controlling the microbial growth, but the packaging systems of the airtight containers and the zipper bags was not significantly affect the quality parameters for 2-thiobarbituric acid(TBA), color, and sensory quality.

• Journal of Biosystems Engineering
• /
• v.25 no.1
• /
• pp.33-38
• /
• 2000

This study was performed to investigate airtight storage characteristics of rough rice using airtight flexible pve container. A storage test of rough rice of 4 tonnes was carried out to determine the changes of gas composition of air in the container, grain moisture content, air temperature and relative humidity , the presence of insects ,germination rate, crack ratio , fat acidity , 1000-kernel weight, and brown rice recovery over storage period of 5 months in Suwon. Concentration of oxygen was decreased from 20% to 16% and carbon dioxide was increased of from 0.03% to 1.6%. The grain moisture content was decreased from 14.4%(w.b) to 14.1%(w.b) for 5 months storage period . Insect population levels were low but these increased after 5 months storage. Most of insects were dead, Fat acidity increased from 7.5(mg KOH/100g) to 10.2(mg KOH/100g). Other storage factors such as germination rate, brown rice recovery and 1000-kernel , and 1000-kernel weight slightly decreased and crack ratio was slightly increased. Qualities of rough rice during 5 months storage period under hemetic air conditions were maintained fairly good considering the above changes of quality factors during storage.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.2
• /
• pp.249-257
• /
• 2013

This study is being performed to confirm the container effects during the fermentation processes of kimchi. Kimchi fermentation was prepared in the laboratory with four different types of containers; namely, a traditional Onggi vessel (Korean traditional clay pot, TOV), plastic airtight covered Onggi vessel (PAOV), plastic covered vessel (PCV) and plastic airtight covered vessel (PACV). The kimchi fermentation in the different containers was followed by taking samples at 48 hour intervals for 10 days. In all fermentation containers, the pH changes of kimchi were decreased with fermentation days, while salt content was the same for all types of containers. The number of lactic acid bacteria in kimchi were $1.09{\times}10^8$ $CFU/m{\ell}$ at first. But the TOV, PAOV, PCV, and PACV after fermentation for 10 days were $1.42{\times}10^{10}$, $9.13{\times}10^9$, $4.93{\times}10^9$ and $7.46{\times}10^9$ $CFU/m{\ell}$, respectively. The kimchi fermented in the TOV with the most dominant bacterial species were the following 5 strains: Bacillus subtilis, B. licheniformis, B. safensis, Lactobacillus brevis and B. pumilus. The use of different types of containers therefore influenced the number of L. brevis and the four Bacillus species. in kimchi, and may influence the characteristics of the fermented kimchi products. The TOV offered the greatest L. brevis numbers and suggested that it could be the best suited for preparing traditional kimchi fermentation.

• Korean Chemical Engineering Research
• /
• v.50 no.2
• /
• pp.264-269
• /
• 2012

Die slide injection marvelously reduces the cost and time in processing plastic products because they can simplify the conventional process through eliminating additional process. However, this process must resolve some defects like whitening, resin infiltration, blowhole, resin overflow, etc. In this study, the process parameters of the injection molding are optimized by using the finite element method and Taguchi method. The injection molding analysis is simulated by employing the Moldflow insight 2010 code and the 2nd injection is by adopting the Multi-stage injection code. The process parameters are optimized by using the $L_{16}$ orthogonal array and smaller-the-better characteristics of the Taguchi method that was used to produce an airtight container (coolant reservoir tank) from polypropylene (PP) plastic material.rodanwhile, the optimum values are confirmed to be similar in 95% confidence and 5% significance level through analysis of variance (ANOVA). rooreover, new products and old products were compared by mdasuring the dimensional accuracy, resulting in the improvement of dimensional stability more than 5%.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.25 no.2
• /
• pp.31-35
• /
• 2019

Kimchi is a refreshing sour food which gives sour and carbonic acid taste of carbon dioxide produced during the fermentation process. So, carbon dioxide injection was tried to raise carbonic acid taste of kimchi stored in the airtight container. First, carbon dioxide injection times of a given gas supply system were determined experimentally to attain initial concentration of 80% for different solid/liquid ratios. Since carbon dioxide is dissolved in kimchi to decrease its concentration during storage, periodical carbon dioxide injection conditions were needed and determined to keep the $CO_2$ concentration above 70%. For the initial flushing to 80% $CO_2$ concentration in model system filled with water, the injection time ranged from 40 to 89 seconds for free volumes of 2-8 L. $CO_2$ injection conditions for the under-ripened storage at $10^{\circ}C$ consisted of longer time at more frequent cycles for watery kimchi than for Chinese cabbage kimchi. At $0^{\circ}C$ of subsequent ripened stage storage of watery kimchi, the periodical injection at 3 hour interval was required because of continuous dissolution of carbon dioxide. However, Chinese cabbage kimchi did not require subsequent $CO_2$ injection during the ripened state storage and needed only flushing to 80% $CO_2$ at time of the container opening and closing. These results can be used as basic information for the programmed control of $CO_2$ injection in the kimchi container system.

• Korean Journal of Food Science and Technology
• /
• v.41 no.1
• /
• pp.11-15
• /
• 2009

Commercial tofu was cut and re-packed in a vacuum container, an airtight container and an open tofu tray in an effort to assess the effects of vacuum containers on the shelf life of leftover tofu. The re-packed tofu were stored at $5^{\circ}C$ and $25^{\circ}C$ for the enumeration of total bacteria and coliforms. We also measured changes in color, pH, and opacity. The vacuum retarded the bacterial growth under $10^5$ CFU/mL for up to 12 days at $5^{\circ}C$. The color of the tofu was unaffected by the container type at both storage temperatures, whereas the pH and opacity of the immersion solution were altered less profoundly by storage in the vacuum container at $5^{\circ}C$. However, we noted no significant differences in bacterial growths, pH, and opacity among container types at $25^{\circ}C$. The results of this study showed that the usage of vacuum containers may be a favorable method for the preservation of tofu under refrigerated conditions.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.25 no.2
• /
• pp.259-267
• /
• 1998

For more than two decades, many investigators have tried a variety of methods for delivering antimicrobial agents to the oral cavity with the objective of eliminating mutans streptococci. In the belief that the effectiveness of chemotherapy might be improved by a more effective delivery system, the intention of the present study was to exploit a new drug delivery system delivering chlorhexidine to the oral cavity. The vehicle delivering chlorhexidine tested in this study was self-curing acrylic resin(polymethyl methacrylate). The powder of the acrylic resin was polymerized with the 5 different liquid preparations, in which $Chlorzoin^{(R)}$ was mixed with five different monomer/Chlorzoin ratios immediately prior to the polymerization, in a stainless steel mold ($40mm{\times}40mm{\times}2mm$). A total of 50 cured resin specimens were divided into 5 groups according to the different monomer preparations. Every specimen was soaked in an airtight container filled with distilled water (100 ml) and then kept in an incubator at $37^{\circ}C$. The solutions (0.8 ml) were collected from the container at every 24 hours, and the amount of released chlorhexidine in the solutions was measured in an ultraviolet spectrophotometer at 250nm. The container was refilled with distilled water every after measurement. This procedure was repeated for 14 days. It was found that chlorhexidine was continuously released from all of the 50 specimens during the experimental period. And it was noted that the pattern of chlorhexidine release was a type of sustained-release preparation, that is, the amount of the released chlorhexidine at the first day in all 5 groups was high (p<0.0001), and then the release was decreased during the rest of the experimental period (p<0.001).

• The Plant Pathology Journal
• /
• v.27 no.3
• /
• pp.257-265
• /
• 2011

During 2002-2008 in Korea, 455 extracts from myxobacteria consisting of 318 cellulolytic and 137 bacteriolytic myxobacteria were isolated, which were then screened for antifungal activity against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Penicillium sp., Pyricularia grisea, and Phytophthora capsici. 204 isolates had antifungal activity, causing both a clear zone due to blocked spore germination and inhibition of mycelial growth; most (199) were from cellulolytic (Sorangium cellulosum) and only five were from bacteriolytic myxobacteria. B. cinerea, the best controlled among the five tested pathogens, had a unique group of antifungal isolates of myxobacterial extracts compared to the other pathogens' groups. Among seventy-nine bioactive myxobacteria, four isolates, KYC 3130, KYC 3247, KYC 3248 and KYC 3270, were selected and all were cellulolytic. Liquid culture filtrates of these four myxobacteria were applied to tomato, cherry tomato, strawberry, and kiwi fruits 5 h before inoculation with gray mold conidia; then the treated fruits were placed in an airtight container and the experiment was repeated six to eight times. Incidence (%) of gray mold on fruit of the infected control treatment was 84-98%, whereas it was only 5-21% after the KYC 3270 treatment. After KYC 3270 treatment of the four fruits, mold control was 79-95%, which was highest among the filtrates and statistically the same as treatment with fludioxonil, a registered chemical against gray mold of stored fruits.

• Korean Journal of Heritage: History & Science
• /
• v.34
• /
• pp.196-209
• /
• 2001

Kunjung-mun Gate the only existing multi-level palace gate from the Chosun Dynasty, is the main fate of Kungjung-jun, the central building of Kyungbok-koong Palace. Sangryangmun(a written record of the construction of the ridge beam) of Kunjung-mun Gate was discovered in a hole under its main beam during the renovation project on September 19th, 2000. At the time of discovery, Sangryangmun was found in its original state as a rolled up scroll. On a clould-patterned, red silk cloth, 78 cm in width and 1200 cm in length, each of all 92 lines of the Kunjung-mun Sangryangmun is comprised of either 7 or 11 brush-written, ornamental "Seal" characters. With an exception of its discoloration, the material is considered well preserved. After its discovery, the National Institute of Cultural Properties stored the document in an airtight container for a permanent preservation. In accordance to the Royal Command at the time, the Kunjung-mun Sangryangmun was composed by Kim Byungi, then written by Lee Donsang on January 19th 1867. This document records the meaning and the process of the repair effort of Kunjung-mun Gate includes the wish for peace and longevity of the Chosun Kingdom and its people.

• 유체기계공업학회:학술대회논문집
• /
• 2003.12a
• /
• pp.143-148
• /
• 2003

This study was experimentally performed in order to estimate the errors due to the leakage of transmitter gaugelines in the orifice flow meter for natural gas. It would be a serious problem in safety if a large quantity of leak was occurred at the tubes or fittings like valve. But in most cases the safety problems might be rarely happened because the gas leak detectors could be operated in advance and the various kinds of inspection would be also fulfilled periodically. If the leakage was occurred continuously with an undetectable amount at the gaugelines for measuring the pressure or the differential pressure(DP), the amount of leakage might be an error or an unaccounted flow(UAE). In addition if the measuring value of pressure or DP were affected by the leakage, it might also be a measurement error. The experiments were performed to estimate the amount of leakage and to check the DP changes if it exited. First, through the measurement of the air pressure changes in the airtight container connected to a transmitter with gaugelines as the time passed, the amount of leakage causing from the fittings of gaugelines was roughly estimated. As changing the leak position of the gaugeline, the leak was intentionally made to break out. The variance of DP was checked as controlling the extent of leakage and compared to no leak conditions. Consequently, under the normal maintenance conditions, the result represented that the amount of leakage causing from the gaugelines was insignificant and also the DP changes on leakage conditions were too small to cause the errors of measurements.