• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.91-95
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• 2002

Effects of freeze-drying time on the microbiological, sensory, and other characteristics of freeze-dried kimchi were investigated to optimize freeze-drying time for kimchi. Quality attributes of freeze-dried kimchi, including number of lactic acid bacteria (LAB), pH, sensory properties, brittleness, rehydration property, moisture content, and microstructure of Chinese cabbage were observed for 24, 48 and 72 h, respectively. Number of LAB and pH of the kimchi freeze-dried for 24 h were significantly changed in comparison with those of the kimchi not freeze-dried. However, further freeze-drying did not change markedly number of LAB and pH. Overall acceptability of the sample freeze-dried for 48 of 72 h was better than that of the sample freeze-dried for 24 h. As freeze-drying time increased, brittleness of the dried sample increased, and rehydration property was improved while dried weight and moisture content of the sample decreased. In conclusion, the sample freeze-dried for 48 h was better than the sample freeze-dried for 24 or 72 h, based on sensory properties and other characteristics.

• Journal of the Korean Society of Food Culture
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• v.10 no.1
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• pp.67-74
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• 1995

This study researched microbial change of quality according to the various phases of product flow of cooked pea and rice, cold cucumber and seaweed soup, soybean sprouts japchae feeding urban type of a commissary school and a satellite school in Daejeon area, also it suggested the possibility that the central commissary foodservice system can be established and utilized more developmental to identify its food of variation of temperature and state of safety unitl 3 hours after cooking for the case of delay of distribution and holding because of the satellite school of geographical location and traffic problem. The critical Control Points identified for each category of menu items were: Boiled pea and rice: inadequate distribution, holding and storing before assembly; Cold cucumber and seaweed soup: pre-preparation and post-preparation after cooking; Soybean sprouts japchae: Pre-preparation, post-preparation and storing. As the result of observation of the variation of temperature and microbial safety according to the delay of distribution and holding for each food, all of them were relatively safe until 3 hours after cooking, but cold cucumber and seaweed soup being stored for 3 hours, the value of E. coli is $10^3$ CFU/g. The variation of temperature was more extreme in soybean sprouts japchae than cooked pea and rice and cold cucumber and seaweed soup. It was proved that the stainless container was excellent and that adequate holding container should be used.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.289-295
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• 2009

To develop a safer yogurt for immuno-compromised or allergy patients and to extend shelf-life, a plain yogurt was irradiated with doses of 0, 1, 3, 5, and 10 kGy using a gamma ray and the chemical and microbiological quality and allergenicity change were investigated. There was no difference in the content of protein, total solid, and amino acids of the plain yogurt by irradiation treatment and different storage temperatures (4, 20, and $35^{\circ}C$). The lactic acid bacterial counts of irradiated plain yogurt had approximately 3-decimal reduction at 3 kGy, and no viable cell at 10 kGy regardless of storage time and temperature. The binding ability of rabbit antiserum to milk proteins in irradiated plain yogurt showed that 10 kGy of irradiation produced significantly higher binding ability than other treatments. Sensory evaluation indicated that only appearance of the plain yogurt irradiated at 3 kGy or higher had a lower value than the non-irradiated control when stored at $20^{\circ}C$. Results suggest that irradiation of plain yogurt does not significantly affect the chemical and sensory quality of plain yogurt, but can extend the shelf-life, possibly reduce allergenicity, and provide a safer product.

• Journal of Microbiology
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• v.34 no.3
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• pp.263-263
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• 1996

Infection of fish cells with IHNV resulted in gradual increase in cytosolic free $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ in CHSE, gradual decrease in $[Ca^{2+}]_i$ in FHM, and no significant change in RTG cells. The degree of $[Ca^{2+}]_i$ increase or decrease was dependent on the amount of infectious virus, and these $[Ca^{2+}]_i$ variations were maximal at 16 hours after virus infection (p. i.) in both cell lines. When the fish cells were infected with inactivated IHNV, evident variation in $[Ca^{2+}]_i$ was not observed. Thus, infectivity of IHNV appears to correlate with changes in $[Ca^{2+}]_i$ in virus-infected cells. These IHNV-induced $[Ca^{2+}]_i$ changes were partially blocked by cycloheximide, but not affected by cordycepin. It seems to be that virus-induced $Ca^{2+}$ variations were more related with protein synthesis than RNA synthesis. Various $Ca^{2+}$ related drugs were used in search for the mechanisms of the $[Ca^{2+}]_i$, changes following IHNV infection of CHSE cells. Decreasing extracellular $Ca^{2+}$ concentration or blocking $Ca^{2+}$ influx from extracellular media inhibited the IHNV-induced increase in $[Ca^{2+}]_i$, in CHSE cells. Similar results were obtained with intracellular $Ca^{2+}$ blockers. Thus it is suggested that both the extracellular and the intracellular $Ca^{2+}$ sources are important in IHNV-induced $[Ca^{2+}]_i$ increase in CHSE cells.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.287-292
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• 2002

The composition of bacterial communities was detected in surface water of Cheonho Reservoir dominated by cyanobacteria, using fluorescent in situ hybridization (FISH) method. Total bacterial numbers were very high ranging from 0.6～$1.3{\times}10^7 \cells{\cdot}ml^-1$, whereas the ratio of Eubacteria to total bacteria was 29.8~45.8%, which was lower than that in other freshwater ecosystems. On average only 2.1% of DAPI-stained bacteria were detected by FISH with probes for $\alpha$, $\beta$, and $\gamma$-groups, respectively. Unknown eubacteria which was not bound to any probes except EUB 338, was relatively high. On the other hand, the Cytophaga-Flavobacterium group increased following the change of dominant species from Anabaena sp. to Microcystis sp. This result showed that bacterial communities could be affected by phytoplanktons, especially cyanobacteria.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.319-325
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• 2010

The purpose of this study is to investigate the soil compositions, methane production, the number of methanogens, and the community structure of methanogens in rice paddy soils and dry field farming soils in the summer and autumn seasons. As a result of the analysis of soil compositions, any regular tendency to increase or decrease has not been found in most soil samples due to the change of seasons. It has also been found that more methanogens exist in the rice paddy soil that utilize organic farming practices and emptiness farming practices than in the dry field farming soil. The fewer numbers of methanogens utilizing the acetate have been found than those of the methanogens utilizing the hydrogen or the formate. In an experiment of methane production, the methanes increased for two weeks when the acetate was added, but they continued to increase for seven weeks more when the formate and the hydrogen were added. In the phylogenetic analysis using the mcrA gene, the methanogens had diverse clusters in the rice paddy soil, whereas the methanogens were concentrated only in a few clusters in the dry field farming soil.

• Fisheries and Aquatic Sciences
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• v.20 no.7
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• pp.13.1-13.7
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• 2017

In order to evaluate the maximal storable period of the raw crab for a non-thermal muscle separation, the quality changes of the leg meat of red snow crab (Chionoecetes japonicus) during freeze storage were investigated. Fresh red snow crabs were stored at $-20^{\circ}C$ for 7 weeks, and the leg muscle was separated by a no heating separation (NHS) method every week. During the storage, considerable loss of the leg muscle did not occur and microbiological risk was very low. In contrast, discoloration appeared at 2-week storage on around carapace and the leg muscle turned yellow at storage 3-week. In physiochemical parameters, protein and free amino acids gradually decreased with storage time, expected that proteolytic enzymes still activated at $-20^{\circ}C$. At 4-week storage, the sensory acceptance dropped down below point 4 as low as inedible and notable inflection points in pH and acidity were observed. The volatile base nitrogen was low, though a little increase was recorded. These results suggested that the maximal storable period at $-20^{\circ}C$ of the raw material was within 2 weeks and it was depended on external factor such as the discoloration. The present study might be referred as basic data for approaches to solve quality loss occurred in non-thermal muscle separation.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.159-166
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• 1996

To evaluate hepatoprotective effects of G009, an hepatoprotective agent which was extracted from the mycelia of Ganoderma lucidum IY009, we were, studied using $CCl_4$-and galactosamine-induced hepatotoxicity in rats. The ratio of liver weight to body weight, the value of glutamic oxaloacetic transaminase(GOT) and glutamic pyruvic transaminase (GPT) activities, the change of a lipids in serum, and the inhibitory activity of malondialdehyde (MDA) formation in serum and liver homogenate were determined in rats. G009 was not significantly changed of the ratio of liver weight to body weight and the content of lipids in serum, but reduced the serum GOT and GPT values in $CCl_4$-and galactosamine-induced hepatotoxicity in rat. Especially, protective effect of G009 on rat hepatic injuries induced by galactosamine was significantly appeared. $CCl_4$ increased markedly the formation of lipid peroxides in the liver homogenate, and serum. The increase of lipid peroxides by $CCl_4$-induced hepatotoxicity was markedly reduced by the treatment with G009. These results suggest that the hepatoprotective effects of G009 may be correlated with its anti-lipid peroxidative activity, therefore, it may be potential agent for hepatic disease.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.677-683
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• 2016

To enhance the physiological activities and reduce the off-flavor of garlic in kimchi, we manufactured kimchi seasoning replaced with 25~75% black garlic, we evaluated microbiological, physico-chemical and sensory evaluation. The changes of total aerobic and lactic acid bacteria were similar between the control and the kimchi seasoning replaced with black garlic during storage periods. The lightness of the kimchi seasoning replaced with black garlic was lower than that of the control and decrease of lightness was proportional to the concentration of black garlic. The redness and yellowness of the kimchi seasoning replaced with black garlic were decreased to the concentration of added black garlic and changes of the redness in all the samples were slightly increased during storage periods. But the yellowness did not change during storage periods. The changes of pH and acidity did not differ between the control and the samples of replaced with black garlic during storage periods. The sensory parameters including taste and flavor did not differ among treatments during storage periods. But color and overall acceptance of the control and sample replaced with 25% black garlic were higher than those of the samples replaced with 50 and 75% black garlic.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.536-541
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• 2013

Background Pathogens in the nasal cavity during nasal surgery could lead to a systemic infectious condition, such as bacteremia, nosocomial infection, or toxic shock syndrome. However, there is no research about the prevalence of nasal carriage in patients with nasal bone fracture. Methods This was a prospective, double-blind, randomized study about the rate of nasal carriage in 200 patients with nasal bone fracture in Korea. Nasal secretions were taken from both the middle nasal meatus and colonized. All analyses were carried out using SPSS software. Results Pathogens were identified in 178 of the 200 cases. Coagulase-negative staphylococci (CNS) were the most cultured bacteria in 127 (66.84%) of the 190 total patients after excluding 10 cases of contaminated samples, and methicillin-resistant coagulase-negative staphylococci (MRCNS) were found in 48 (25.26%). Staphylococcus aureus was the second most identified pathogen, found in 36 (18.95%), followed by 7 cases (3.68%) of methicillin-resistant Staphylococcus aureus (MRSA). The prevalence rate of MRSA in the females was higher than that in the males (RR=4.70; 95% CI, 1.09-20.18), but other demographic factors had no effect on the prevalence rate of MRSA and MRCNS. Conclusions The prevalence rate of these pathogens in patients with nasal bone fracture in Korea was similar to other reports. However, few studies have addressed the prevalence rate of CNS and MRCNS in accordance with risk factors or the change in prevalence according to specific prophylaxis against infectious complications. Additional research is needed on the potential connections between clinical factors and microbiological data.