• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.746-751
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• 2015

The quality characteristics of Oenothera biennis juice (OJ) fermented with various concentrations of sugar solutions (50, 60, and $70^{\circ}Brix$) and at different temperatures (20 and $30^{\circ}C$) were investigated. The sugar concentration and pH of fermented OJ decreased during fermentation and more rapidly decreased at $30^{\circ}C$ rather than at $20^{\circ}C$. The number of total bacteria increased during 6 days of fermentation and decreased gradually thereafter, and coliform bacteria were not detected after 8 to 10 days of fermentation at 20 and $30^{\circ}C$. Enzyme activities (invertase, amylase, and cellulase) of fermented OJ with $50^{\circ}Brix$ sugar solution were the highest among the different treatments after fermentation for 4 days at $30^{\circ}C$. Total polyphenol content and DPPH radical scavenging ability increased during fermentation. The highest total polyphenol contents and DPPH radical scavenging ability were 7.1 mg TAE/mL and 58.6%, respectively, when fermented at $30^{\circ}C$ with $50^{\circ}Brix$ sugar solution.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.445-451
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• 2010

Antioxidant activities of ethanol extracts of Rumex crispus (RC) were investigated in vitro. Contents of total polyphenols and total flavonoids in RC ethanol extracts were $108.24{\pm}3.29\;{\mu}g/mg$ and $33.06{\pm}2.24\;{\mu}g/mg$, respectively. The antioxidant capacities of RC extracts were high. The RC extracts were capable of directly scavenging DPPH free radicals by acting as reducing agents. This study was also conducted to evaluate the quality characteristics of seasoned pork treated with RC extracts during storage at $4^{\circ}C$ for 21 days. Seasoned pork was produced containing 0, 1, and 3% RC extracts and 0.1% BHA. The DPPH scavenging effect of the seasoning sauces was increased by the addition of RC extracts. The total bacteria and TBARS values of seasoned pork with RC extracts were decreased compared to control, whereas coliform bacteria were not detected after longer storage periods. With regards to sensory evaluation, seasoned pork treated with 1% RC had stronger odor, juiciness, and tenderness compared to seasoned pork. These results suggest that it is possible to manufacture seasoned pork with RC extracts for the improvement of shelf-life and quality.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.38-46
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• 2005

To determine the actual hygienic status of domestic chicken meats sold in public markets (conventional markets and department stores), microbial contamination levels (Total cells, Coliforms and Staphylococcal cells) and zoonotic pathogens (Salmonella species, Campylobacter species, Listeria species, and Staphylococcus aureus) isolation tests were conducted. Chicken meats and eggs tested were collected from the conventional markets (Si-Jang) and department-stores located in Seoul and Kyung-gi regions in 1996. In total cells and coliforms contamination tests, chicken meats sold in department stores were much lesser contamination status than those of Si-Jang, but staphylococcal cells level was much more higher than that of conventional markets. Salmonella isolation frequency was investigated as $68.8\%$, but Campylobacter jejuni and Listeria monocytogenes isolation frequency were appeared both $64.0\%\;and\;63.3\%$. In case of eggs sold in public markets, one of S. gallinarum strain $(0.7\%)$ was isolated only on the egg-shell part among the four-hundred and fourty-six. In comparison with foreign imported chicken meats, there were no big differences in microbial contamination status. On the other hand, both Salmonella and L. monocytogenes were isolated only in the chicken wings from Korea and China, but not from U.S.A. This data suggest that more hygienic control system in order to produce the safe and hygienic chicken meats and eggs is need in our country as soon as possible.

• Microbiology and Biotechnology Letters
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• v.8 no.3
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• pp.155-166
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• 1980

Studies have teen undertaken to investigate the degree of microbial contamination in the subsidiary materials which have been known as an important source of microorganisms associated with spoilage of fish sausage and fish paste products. Twenty hinds of food ingredients including starch, spices and condiments, 59 samples in total collected from commercial fish sausage processing plants and supermarket in the period of July to October 1979, were examined for standard plate count, coliform and fecal coliform, mold and yeast, thermoduric microorganisms, aerobic sporeformers (mesophilic and thermophilic), anaerobic sporeformers (mesophilic and thermophilic) and sulfide spoilage anaerobes. The results obtained are summarized as follows. 1. Among the food ingredients examined, corn starch, black pepper, hot pepper, onion, garlic, ginger, beef extract and frank marked high bacterial contamination with general and sporeforming microorganisms. And bacterial content of marked samples were generally higher than that of the samples from plants. 2. The high standard plate count caused by high content of these bacteria like thermoduric, mesophilic or thermophilic sporeforming aerobes. 3. Bacterial content of food ingredients such as black pepper and beef extract being used in plants, and black pepper, hot pepper, onion and garlic from the market were exceeded the bacterial standards being enforced in Japan and U. S. A. 4. Average standard plate count was in the range of 10$^4$to 10$^{5}$ /g for black pepper, wheat flour, onion and garlic collected from plants, and 10$^{5}$ to 10$^{7}$ /g for black pepper, hot pepper, onion and garlic from market. No plate count was observed in pepper essence and coloring material. 5. Coliform organism was detected in starch, black pepper, hot pepper, onion, garlic, ginger and gluten that showed high standard plate but no fecal coliform in the samples except black pepper and hot pepper. 6. Average mold and yeast count was 140 to 460/g for corn starch, wheat flour and black pepper from plants, and 10$^3$/g for black pepper and hot pepper from market. No count was observed in the other ingredients. 7. Sulfide spoilage sporeforming anaerobes boiled for 5 min. at 10$0^{\circ}C$ and incubated at 55$^{\circ}C$ was not detected in all the samples examined.

• The Korean Journal of Pesticide Science
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• v.18 no.2
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• pp.88-94
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• 2014

Among pre-harvest environmental factors, increasing attention has been paid to the effects of chemical and microbiological factors on fresh produce. The occurrence and prevalence of these factors have been usually studied with regard to the final products at the post-harvesting stage and/or when they are sold in the market. However, the origin and routes of transmission of both factors remain to be clarified. In the present study, we examined the contamination levels of food-borne pathogens and chemical factors such as pesticide residues and heavy metals in 83 and 43 samples, respectively, including various soil, water, and fertilizer samples, as well as post-harvested and processed samples. Among the organic farming samples, only one pesticide, dimethomorph, was detected in the soil sample, however no pesticides were observed from any other samples in organic farming system. Thus, it was thought that might be contaminated from conventional farm land in the vicinity. Whereas many pesticide residues were detected in conventional farming systems such as soil, fertilizer, water, and fresh produce as expected. Furthermore, heavy metals detected from all tested samples did not shown contamination levels higher than the standard limit. We comparatively assessed the levels of contamination by food-borne pathogens on the samples from organic and conventional farming systems, and found aerobic bacteria at approximately 7 log CFU/g, with no significant differences observed between the two systems. Coliforms were present at lower levels than aerobic bacteria. No human pathogens were present among the coliforms detected, indicating that these bacteria are saprophytes without the ability to cause food-borne illnesses. In contrast, among the high-risk food-borne pathogens, only sporadic cells of Bacillus cereus were found on samples of organic farming system. These data extend previous findings that the most prevalent food-borne pathogen is B. cereus and demonstrate that it spreads to whole living plants via soil.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.347-355
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• 1986

The Sonakdong river is very important water source not only for agricultural water of Kimhae field but also for fishery water. Recently the middle and lower areas of the river have the tendency to be heavily contaminated by domestic sewage and agricultural chemicals. Fifty six water samples were collected from 8 stations from July to December in 1985 for the experiment (Fig. 1). To evaluate the water quality, pH, water temperature, electrical conductivity, chloride ion, nutrients ($NO^{-}_{2}-N,\;NO^{-}_{3}-N,\;NH^{+}_{4}-N,\;PO^{3-}_{4}-P,\;SiO_2-Si$), total coliform, fecal coliform, and fecal streptococcus were determined. Range and mean value of the samples were as follows; pH $6.3{\sim}9.4$, 7.91; water temperature $6.1{\sim}34.8^{\circ}C,\;23.88^{\circ}C$; electrical conductivity (from St. A to G) $1.575{\times}10^2{\sim}30.50{\times}10^2{\mu}{\mho}/cm,\;6.57{\times}10^2{\mu}{\mho}/cm$; chloride ion $23.5{\sim}14,300mg/l$, 770.0mg/l; nitrite-nitrogen $0.007{\sim}0.110mg/l$, 0.053mg/l; nitrate-nitrogen $0.001{\sim}1.638mg/l$, 0.649 mg/l; ammonia-nitrogen $0.017{\sim}4.200mg/l$, 0.497mg/l; phosphate-phoshorus $0.011{\sim}0.281mg/l$, 0.086mg/l; and silicate-silicious $2.4{\sim}6.5mg/l$, 4.43mg/l. Electrical conductivity and chloride ion of the station F(Chomanpo) were $2.676{\times}10^2{\mu}{\Omega}cm$ and 123.99mg/l which were lower than those of others. Among the analyzed nutrients, silicate-silicious concentration was the highest through all the samples. The bacterial density of the samples ranged $36{\sim}110,000/100ml$ for total coliform, $15{\sim}46,000/100ml$ for fecal coliform and $3.6{\sim}15,000/100ml$ for fecal streptococcus. The range and the mean of the TC/FC ratio were $3.0{\sim}9.6$, 5.51 and those of the FC/FS ratio were $1.1{\sim}9.2$, 6.19, respectively. On the other hand, fecal coliform was not detected in about $78\%$ of the water samples examined. Composition of coliform was $52\%$ Escherichia coli group, $3\%$ Citrobacter freundii group, $13\%$ Enterobacter aerogenes group and $31\%$ others.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.250-257
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• 2006

The purpose of this study is to evaluate microbiological contamination of leafy vegetables. Total aerobic bacteria and coliforms were monitored to get the contamination levels and Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni to detect pathogens with risk of foodpoisoning from fresh vegetables. The colony count of total aerobes and coliforms was also performed to determine the efficacy of washing with tab water by common consumers. 124 samples which are divided into 8 kinds of vegetables - Sesame leaf, Dropwort, Chinese cabbage, Korean leek, Lettuce, Crown daisy, Pimpinella brachycarpa, Chicory were sampled in 2 wholesale markets in Incheon. Mean counts of total aerobic bacteria for individual vegetables ranged from $2.2\times10^6\;CFU/g\;to\;6.0\times10^7\;CFU/g$ and total coliforms were from $4.1\times10^5\;CFU/g\;to\;9.8\times10^6\;CFU/g$. Both show the peaks in summer on this study from March to September. Decrease rates after washing with tab water averaged 81.0% and 82.5% in total aerobic bacteria and coliform counts respectively. Staphylococcus aureus was isolated 8.1%, Bacillus cereus 14.5%, Clostridium perfringens 5.6%, Escherichia coli 18.5%. 11 samples showed overlapped bacterial contamination. For respective vegetables Staphylococcus aureus isolated from 0.0% to 22.2%, Bacillus cereus from 0.0% to 29.4%, Clostridium perfringens from 0.0% to 23.1 %, Escherichia. coli from 0.0% to 35.0%. Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni were not isolated. This study is expected to be available as the reference for the basal data of pathogens in fresh vegetables.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.511-522
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• 1984

The Nagdong is one of the biggest rivers in Korea, which is very important water source not only for tap water of Pusan city but also for the industrial water. Therefore, authors tried to check the water quality year by year. In this experiment one hundred and twenty water samples collected from August 1983 to July 1984 were analyzed bacteriologically and physiologically. Fifteen sampling stations were established between near Samrangjin and estuary of the river. To evaluate the water quality, temperature, pH, chloride ion, salinity, chemical oxygen demand (COD), electrical conductivity, nutrients, total coliform, fecal coliform, fecal streptococcus, viable cell count and bacterial flora were observed. The variation of water temperature was ranged $-1.5{\sim}29.0^{\circ}C$ (Mean value $13.9{\sim}16.5^{\circ}C$), it in spring was higher as $10{\sim}15^{\circ}C$ about $10^{\circ}C$ than in winter and it in autumm was very stabilized as about $20^{\circ}C$ at each station. The pH variation of the samples was ranged $6.68{\sim}9.15$. The range of concentration of chloride ion and salinity varied $7.4{\sim}l,020.5$ mg/l and $1.05{\sim}33.0\%0$, respectively. Especially, salinity of the 3rd water war was the higher than others as $25.76{\sim}31.58\%0$. COD was ranged $1.45{\sim}14.94$ mg/l and the lower part of the Nagdong River was heavily contaminated by domesitc sewage and waste water from the adjacent factor area. The range of electrical conductivity was $1.360{\times}10^2{\sim}5.650{\times}10^4{\mu}{\mho}/cm$ and that was by far higher the estuary than the upper. Concentration of nutrients were $0.008{\sim}0.040$ mg/l (Mean value $0.019{\sim}0.068$ mg/l) for $NO_2-N,\;0.038{\sim}5.253$ mg/l ($0.351{\sim}2.347$ mg/l) for $NO_3-N,\;0.100{\sim}2.685$ mg/l($0.117{\sim}1.380$ mg/l) for $NH_4-N,\;0.003{\sim}0.084$ mg/l($0.014{\sim}0.065$ mg/l) for $PO_4-P$ and $0.154{\sim}6.123$ mg/l ($1.165{\sim}3.972$ mg/l) for $SiO_2-Si$, respectively. Usually nutrients contents of the water in the upper part(included station 1 to 5) were higher than those of the estuarine area. The bacterial density of the samples ranged 7.3 to 460,000/100 ml for total coliforms, 3.6 to 460,000/100 ml for fecal coliform, $0{\sim}46,000/100ml$ for fecal streptococcus and $<30{\sim}1.2{\times}10^5/ml$ for viable cell count. Composition of coliform was $28\%$ Escherichia coli group, $18\%$ Citrobacter freundii group, $31\%$ Enterobacter aerogenes group and $22\%$ others. Predominant species among the 659 strains isolated from the samples were Pseudomonas spp. ($42\%$), Flavobacterium spp. ($20\%$) and Moraxella spp. ($12\%$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1743-1749
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• 2011

The microbial reduction and quality characteristics of salted Chinese cabbage using electrolyzed water were investigated. The electrolyzed water was used to control the microbes in the processes of primary washing, salting, and secondary washing. The total bacteria, lactic acid bacteria, coliform, pH, salinity, vitamin C, and total sugar were analyzed. After primary washing by electrolyzed water, the total bacteria populations were reduced to 2.78 log cfu/g, and the coliform populations were similarly reduced. After secondary washing by electrolyzed water, the total bacteria population of Chinese cabbage was reduced to a maximum of 1.5 log cfu/g. The salinity of Chinese cabbage and salting solutions increased rapidly over three hours, and then increased slowly. The sterilization effect of electrolyzed salting water could not last beyond 3 hours, because the OHCl concentration of electrolyzed water was reduced by over 90% at the third hours of the salting process. Vitamin C was reduced and total sugar did not change regardless of treatments during the salting process. Consequently, electrolyzed water was effective to remove microbes from salted Chinese cabbages.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.123-131
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• 2017

Norovirus causes frequent epidemic viral gastroenteritis in Korea. The team for the control of noroviral foodborne outbreaks (NOROTECL) executed a project to trace the cause of norovirus contamination in agricultural products and environmental samples to reduce norovirus outbreaks in Korea. Between January and November in 2015, the contaminations by norovirus and indicator microorganisms such as coliforms, Escherichia coil and male specific coliphage (MSC) were examined in 80 agricultural products, 80 soil samples, 78 human feces samples, 3 animal feces samples, 80 agricultural water samples and 80 river water samples. Semi-nested PCR and DNA sequencing revealed 18 genogroup I and 3 genogroup II noroviruses in a total of 18 samples. These noroviruses were validated by real-time (RT)-PCR analysis. For indicator microorganisms, coliform and E. coli were respectively detected in agricultural products (68, 1%), soils (88, 7%), human feces (44, 12.8%), animal feces (67, 67%), agricultural waters (74, 30%) and river waters (96, 51%). The MSC results revealed 14 positive samples.