• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.65-71
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• 2007

Five different commercial chungkukjang powders (A$\sim$E) were compared based on their physicochemical, organoleptic and functional properties. The proximate composition of the five samples ranged from 6.07 to 8.54% in moisture, 15.31 to 27.07% in crude protein, 20.19 to 24.75% in crude lipid, 34.84 to 52.41% in carbohydrate, and 3.69 to 5.26% in ash. The pH of the samples ranged from 5.58 to 6.11, and Hunter's colors showed 70.01$\sim$77.22 for L value, 0.91$\sim$4.64 for a value and 23.72$\sim$31.00 for b value depending on the product. The microbial counts were 8.16$\sim$g.60 log CFU/g for aerobic bacteria, $\sim$4.16 log CFU/g for yeasts & molds, and 1.07$\sim$3.88 log CFU/g for coliforms. The contents of reducing sugars and amino-N were 1.89$\sim$2.41% and 2.83$\sim$7.31%, respectively. Free amino acids were mainly composed of glutamic acid, valine, leucine, phenylalanine, and lysine. The amounts of total phenolics and total flavonoids were 108$\sim$302 mg% and 2.73$\sim$9.41, respectively, with some variations in the products. However, the isoflavone contents, which were composed of genistein (63.26$\sim$217.16${\mu}g/g$), daidzein (58.24$\sim$166.65${\mu}g/g$), genistin (2.66$\sim$55.68${\mu}g/g$), and glycitein (12.26$\sim$17.82${\mu}g/g$), were apparently different per product. The sensory scores for color, smell, taste and overall preference for the five chungkukjang products, which were evaluated by panels in their 20's and 30's using 7-point scoring test, ranged from 3.20 to 4.05.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.59-66
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• 2017

This study investigated the quality characteristics and biological activities of rice germ fermented by Bacillus spp. During the milling process, the contents of rice germ in the rice bran (Control) were adjusted to 30% (RG30) and 70% (RG70). The approximate composition, pH, total acidity, total soluble solid, total sugar, polyphenol and flavonoid contents were measured. DPPH radical scavenging activity, xanthine oxidase (XO) and angiotensin converting enzyme (ACE) activities were also determined. We observed that the moisture content decreased after fermentation, while the crude protein was significantly increased. Fermentation remarkably lowered the pH from 5.83~6.26 to 4.77~4.93, thereby elevating the total acidity. Fermentation also increased the total solid contents, from $0.40{\sim}0.87^{\circ}Bx$ to $1.63{\sim}2.20^{\circ}Bx$. The total sugar decreased to 136.81~151.53 mg/mL from 377.56~450.64 mg/mL. Polyphenol contents were the highest in control (0.59 and 0.73 mg/mL before and after fermentation, respectively). Fermentation significantly affected the increase of the polyphenols in both rice germ 30% and 70% samples, from 0.26 and 0.28 mg GAE/g before fermentation, to 0.52 and 0.70 mg GAE/g after fermentation, respectively. There was a slight increase in the flavonoid contents after fermentation. The $IC_{50}$ value of the electron donating ability, as evaluated by the DPPH method, was the lowest in control (3.77 and 3.36 mg/mL before and after fermentation, respectively). Fermentation increased the XO inhibition activity up to 63.69% in control, 49.81% in rice germ 30%, and 59.32% in rice germ 70%. The ACE inhibition activities were also increased in the fermented control, rice germ 30% and 70%, to 40.51%, 22.69% and 33.91%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.520-526
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• 2013

To determine the kimchi with the best quality and functional characteristics, we manufactured and compared recipes for Korean and Japanese kimchi made either Korean or Japanese baechu cabbages. All batches were fermented for 4 weeks at $5^{\circ}C$, and tested for pH, texture, microbial count, sensory evaluation, DPPH radical-scavenging activity, and cell proliferation (using the MTT assay on AGS human gastric cancer cells). By the third week of fermentation, Korean kimchi made with Korean baechu (KK) and Japanese kimchi made with Korean baechu (KJ) showed a higher acidity than Korean or Japanese kimchi made with Japanese baechu (JK and JJ, respectively). KK ranked highest in springiness, followed by KJ, JK, and JJ. Therefore, the texture of kimchi produced with Korean baechu was appears better than kimchi produced with Japanese baechu. This was confirmed in masticatory tests. Kimchi produced with Korean baechu (KK and KJ) showed lower total aerobic bacterial counts, while the total lactic acid bacterial counts were higher (p<0.05). In sensory evaluation test, KK received the highest overall acceptability score, while JJ earned the lowest score. In the DPPH assay for anti-oxidative activity, KK showed a 94% anti-oxidative effect, followed by KJ (92%), JK (91%), and JJ (88%) (p<0.05). In the MTT assay for analyzing the cell proliferation of AGS human gastric cancer cells, KK showed a 64% anticancer effect in vitro, followed by KJ (57%), JK (38%), and JJ (26%). Therefore, the anti-oxidative and anti-cancer functionalities of kimchi made with Korean baechu were higher than those made with Japanese baechu, regardless of the kimchi recipe applied. Overall, Korean baechu had important and superior effects on the quality and functionality of kimchi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.52-59
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• 1986

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing $28.0\%$ of sorbitol, $14.0%$ of sugar, $5.6\%$ of table salt, $1.8\%$ of monosodium glutamate, $0.6\%$ of garlic powder and $50.0\%$ of water at $5^{\circ}C$ for 15 hours, and dipped for 45 seconds in $10\%$ Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at $45^{\circ}C$ for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally pasteurized in water at $95^{\circ}C$ for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at $25{\pm}3^{\circ}C$.

• Economic and Environmental Geology
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• v.41 no.6
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• pp.645-655
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• 2008

The Cr(VI) concentrations at the shallow aquifer well (MPH-0-1) of the Moonpyung groundwater monitoring station were in the range of 0.5 to 3.1 mg/L exceeding 10 to 62 times the guideline for drinking-water quality, indicating continuous contamination. However, Cr was not detected at the deep bedrock well and the other subsidiary monitoring wells except for MPH-1 and 6. Cross-correlation analyses were conducted for rainfall and groundwater level time series, resulting in the mean time of recharge after precipitation events to be 5.6 days. For rainy season, the water level was raised and the Cr(VI) concentration was several times lower than that during dry season at well MPH-0-1 well. Correlation of the Cr(VI) concentration with the groundwater-level showed that the Cr(VI) reduction was closely related with the groundwater-level rise in the well. However, the groundwater level rise during high water season induced the lateral migration of the Cr(VI)-contaminated groundwater at well MPH-4. We enriched and isolated a chromium reducing bacteria, Enterobacter aerogenes, from the Cr(VI)-contaminated groundwater in the wells MPH-0-1 and MPH-1. The bacteria may play an important role for immobilizing Cr(VI) in the Cr(VI)-contaminated groundwater. Therefore, the migration of the contaminant (Cr(VI) must has been restricted because of the natural attenuation by microbial reduction of Cr(VI) in the groundwater. This research suggests that the bioremediation of the Cr(VI)-contaminated groundwater by the indigenous bacteria may be feasible in the Cr(VI) contaminated groundwater.

• Journal of Nutrition and Health
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• v.50 no.2
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• pp.133-141
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• 2017

Purpose: The objective of this study was to examine the association of temperature-fluctuation with freshness quality in various foods. Methods: We investigated the effects of storage conditions on antioxidant activities of cherries and romaine lettuce during storage at $0.7{\pm}0.6^{\circ}C$, $1.2{\pm}1.4^{\circ}C$, and $1.6{\pm}2.8^{\circ}C$. Cherries and romaine lettuce were stored for a period of 9 days and 7 days, respectively. We also analyzed the effects of storage conditions on fresh quality of beef and salmon during storage at $-0.3{\pm}0.8^{\circ}C$, $-0.6{\pm}2.3^{\circ}C$, and $-1.5{\pm}4.4^{\circ}C$. Both of them were stored for a period of 14 days. Results: The amount of water loss was highest in beef, and the microbial count was also the highest at $-1.5{\pm}4.4^{\circ}C$. In the case of salmon, there was no difference in water loss according to storage, and TBA value was significantly increased at $-1.5{\pm}4.4^{\circ}C$. Moisture retention was the highest at $0.7{\pm}0.6^{\circ}C$ in both romaine lettuce and cherry samples. The contents of polyphenol and flavonoid were significantly higher in cherries, and content of polyphenols in romaine lettuce was significantly higher at $0.7{\pm}0.6^{\circ}C$ (p < 0.05). DPPH activity decreased in the order of $0.7{\pm}0.6^{\circ}C$ > $1.2{\pm}1.4^{\circ}C$ > $1.6{\pm}2.8^{\circ}C$ over 7 days. Conclusion: The results indicate that temperature-fluctuation may affect qualities of foods stored in a refrigerator.

• The Korean Journal of Food And Nutrition
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• v.20 no.1
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• pp.53-62
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• 2007

In this study, physicochemical, microbiological and organoleptic analyses were carried out on cabbage kimchi, a representative fermented food, that was made with 0.5%, 1.0%, and 1.5% mulberry leaf powder during fermentation. This kimchi was then compared to, kimchi without added mulberry leaf powder. The pH values showed minimal differences between the two types of kimchi at the beginning of fermentation. The total acidities were low in every plot of kimchi and increased according to the fermentation. The total microbial cell and Lactobacilus counts increased rapidly in the exponential phase according to the fermentation, and showed little increase in the stational phase. Among the analyzed plots, the lowest population was found in the kimchi containing 1.0% of mulberry leaf powder. This kimchi, in particular, also had the best quality scores, overall acceptance and organoleptic test results during fermentation. Fermentation was slowed in the kimchi with mulberry leaf powder, according to the amount of added as compared to the kimchi without it also showed less acidity. The color appearance, however, of the kimchi with added mulberry leaf powder, was inferior to that of the kimchi without mulberry leaf powder.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.531-541
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• 2013

This study was performed to investigate the antioxidant effect of Sansa (Crataegi fructus) extract in vitro, and to evaluate the functional effects of Sansa powder addition on the quality properties and storage characteristics of Tteokgalbi. Total polyphenol and flavonoid contents of Sansa extract were found to be 127.00 mg/g and 54.05 mg/g, respectively. The DPPH radical scavenging activity of Sansa extract was high and it was similar to the BHA and BHT. The Tteokgalbi was prepared by 0% (N), 0.1% (S1), 1% (S2), and 2% (S3) of the Sansa Powder. Addition of Sansa powder decreased the protein and lipid contents, but the ash content was significantly increased (p<0.05). Increasing the amount of Sansa powder in the pork Tteokgalbi tended to increase the water holding capacity (WHC) values and the cooking loss (p<0.05). The addition of Sansa powder increased the hardness and chewiness values, but did not affect the cohesiveness and springiness values. In the sensory evaluation, the S3 Tteokgalbi had the best score in color. Values of pH, total microbial counts, thiobarbituric acid (TBA) and volatile basic nitrogen (VBN) values decreased significantly added Sansa powder relative to the normal (p<0.05). The S3 Tteokgalbi was significantly (p<0.05) more effective for delaying lipid peroxidation than the other groups. Sansa powder addition increased the L (lightness) and a (redness) values. Therefore, the results demonstrate that adding the Sansa powder to the pork Tteokgalbi tended to improve antioxidative and antimicrobial effects during the chilled storage period.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.916-927
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• 2010

In general water treatment process, the disinfection process by chlorine is used to prevent water borne disease and microbial regrowth in water distribution system. Because chlorines were reacted with organic matter, carcinogens such as disinfection by-products (DBPs) were produced in drinking water. Therefore, a suitable injection of chlorine is need to decrease DBPs. Rechlorination in water pipelines or reservoirs are recently increased to secure the residual chlorine in the end of water pipelines. EPANET 2.0 developed by the U.S. Environmental Protection Agency (EPA) is used to compute the optimal chlorine injection in water treatment plant and to predict the dosage of rechlorination into water distribution system. The bulk decay constant ($k_{bulk}$) was drawn by bottle test and the wall decay constant ($k_{wall}$) was derived from using systermatic analysis method for water quality modeling in target region. In order to predict water quality based on hydraulic analysis model, residual chlorine concentration was forecasted in water distribution system. The formation of DBPs such as trihalomethanes (THMs) was verified with chlorine dosage in lab-scale test. The bulk decay constant ($k_{bulk}$) was rapidly decreased with increasing temperature in the early time. In the case of 25 degrees celsius, the bulk decay constant ($k_{bulk}$) decreased over half after 25 hours later. In this study, there were able to calculate about optimal rechlorine dosage and select on profitable sites in the network map.

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.1-5
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• 2014

Many community gardens in large cities worldwide grow vegetables; however, no information regarding the levels of sanitary indicator bacteria and prevalence of foodborne pathogens in vegetables grown in urban community gardens is available. To evaluate the microbiological quality of vegetables from urban community gardens in Korea, 530 samples (nine types of vegetable, including Chinese cabbage, lettuce, radish leaves, spinach, mustard leaves, crown daisy, leek, Korean cabbage, and chicory) were collected at 11 urban community gardens in Seoul, Korea from September through October 2012. The levels of total aerobic bacteria, Escherichia coli, total coliforms, Salmonella spp. Listeria monocytogenes, and E. coli O157:H7 were evaluated quantitatively and/or qualitatively. The mean numbers of total aerobic bacteria and coliforms were 6.3 log CFU/g (range 3.8-8.1 log CFU/g) and 4.3 log CFU/g (range 2.1-6.4 log CFU/g), respectively. Total coliforms were detected on 67% of whole vegetables. Chicory showed the highest number of total aerobic bacteria and coliforms, whereas the lowest number of coliforms was detected on leeks. E. coli was detected on 2.3% of whole vegetables, including lettuce, radish leaves, mustard leaves, and chicory; however, foodborne pathogenic bacteria were not detected on any of the vegetable samples using this highly sensitive and validated procedure. Based on these findings, the presence of coliforms and E. coli demonstrates that opportunity for improvement of microbiological safety exists throughout the produce production chain, although no major foodborne pathogens were present in vegetables grown in urban community gardens.