• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.459-469
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• 1992

The immobilization characteristics of Zymomonas mobilis for ethanol production were examined. Four different strains of Zymomonas mobilis have been used for ethanol production. Among those, Zymomonas mobilis KCTC 1534 has been selected as the best strain for the highest ethanol productivity from glucose and sucrose. The optimum temperature and pH of the selected strain for ethanol production were $37^{\circ}C$ and 5.0 respectively for both free and immobilized cells. When the cells were immobilized by the gel entrapment method, the immobilized cells could produce ethanol at a little higher temperature than free cells. Calcium alginate was selected as the best gel for immobilizing cells. The immobilized cells could maintain the viability of 80% in 10 weeks storage at $4^{\circ}C$ in the medium with 2% calcium chloride. 20-25 hours of preincubation in 10% glucose solution was required for the activation of immobilized cells entrapped within calcium alginate gel.

• Journal of Korean Medicine for Obesity Research
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• v.9 no.1
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• pp.1-14
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• 2009

Complex microbial communities play an important role in the human health and co-evolved with human in the form of symbiosis. Many literatures provide new evidences that the increased prevalence of obesity cannot be attributed solely to changes in the human genome, nutritional habits, or reduction of physical activity in our daily lives. The intestinal flora was recently proposed as an environmental factor responsible for the control of body weight and energy metabolism. A number of studies suggest that the modulation of gut microbiota affects host metabolism and has an impact on energy storage and demonstrated a role for the gut microbiota in weight gain, fat increase, and insulin resistance. Variations in microbiota composition are found in obese humans and mice and the microbiota from an obese mouse confers an obese phenotype when transferred to an axenic mouse. As well, the gut microbial flora plays a role in converting nutrients into calories. Specific strategies for modifying gut microbiota may be a useful means to treat or prevent obesity. Dietary modulations of gut microbiota with a view to increasing bifidobacteria have demonstrated to reduce endotoxemia and improve metabolic diseases such as obesity. The fermentation of medicinal herbs is intended to exert a favorable influence on digestability, bioavailability and pharmacological activity of herbal extract. Therefore we also expect that the fermented herbal extracts may open up a new area to treat obesity through modulating gut microbiota.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.223-231
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• 2013

This study was carried out for the purpose of inquiring into the effects on shelf-life, quality characteristics, and antioxidant activities, of Majakgwa. This study also regards to the use fermented turmeric powder at varying concentrations in the recipe. The proximate composition of fermented turmeric powder, crude fat, carbohydrate, crude protein, and crude ash was decreased. Viewed division compared to the freeze-dried turmeric curcumin content was increased during fermentation due to the increase of mineral content. With an increased of the amount of fermented turmeric powder used in Majakgwa recipes, the pH of the dough was higher than that of the controlled group. The acid value of Maejakgwa was lowered down, and most effectively controled when adding Turmeric power by 3~6%, and the peroxide value shows high antioxidant ability from the initial storagr period when adding 6%. TBA value appears to have the highest antioxidant ability, when adding 6%, showing lower increasing rate than that of sample group added 0~3% Turmeric powder. When added 9% or more, however, it shows higher TBA value comparing with normal Maejakgwa, the reference group, which indicates on the contrary that the antioxidant ability is lowering. The bitter taste, exterior color, incense of Turmeric, solidity, and crispy level of Maejakgwa with fermented Turmeric powder have been increased significantly as per increase of fermented Turmeric powder, and the sample group added with 9% have shown the best result in the overall taste level. It is anticipated that adding 6~9% of fermented Turmeric powder can increase the storage capability to give the best taste level and effective antioxidant ability by minimizing the off-flavor and bitter taste, through the research as above, which would be the most appropriate blending ratio of Turmeric powder for producing Maejakgwa.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.288-293
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• 2007

In this study, chunggukjang was made from soybeans and Bacillus natto. This chunggukjang was meant to be consumed as a margarine and butter substitute, to help lower trans-fatty acid (TFA) intake. A freeze-dried garlic product was used during fermentation to aid in removing the smell of the chunggukjang. Chunggukjang has a very low fluidity due to its high viscosity; therefore, we added 3%(w/w) soybean oil to improve the fluidity. We found that the TFA content of the garlic chunggukiang paste was no more than 0.02${\sim}$0.05%, which was low compared to the usual contents of margarine and butter. After 4 weeks of storage the TFA content was 0.03${\sim}$0.08%, and it remained within the limits of the permissible amount. The addition of soybean oil allowed this chunggukjang to be made with greater ease, and the freeze-dried garlic eliminated the negative inherent qualities of the chunggukjang. Therefore, this garlic chunggukjang paste could be considered reasonable for commercial production.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.511-516
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• 2006

The objectives of this study was to compare the probiotic characteristics of lactic acid bacteria (LAB) for their ability to assimilate cholesterol, production of bacteriocin, inhibition of angiotensin I-converting enzyme (ACE), and viability under artificial gastrointestinal fluids. Among tested lactic acid bacteria, L167 strain exhibited the highest ACE inhibitory activity (58.75%). The production of ACE inhibitory peptide derived from fermented milk by L167 strain started at the beginning of stationary phase with maximum activity occurring late of the stationary phase. The highest ACE inhibitory activity was observed at 20 h in 10% skim milk medium. L155 strain exhibited cholesterol assimilation activity compared with probiotic strains such as Lactobacillus acidophilus ATCC 43121. With addition of bacteriocin culture, viable cells of Staphylococcus aureus in fermented sausage were slightly decreased during storage. Among selected strains of LAB, 3 strains weve identified as L. plantarum (L155, L165, L167), and two strains were identified as Pediococcus damnosus (L12) and L. paracasei ssp. paracasei (P113) by use of API carbohydrate fermentation pattern and physiological tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.629-634
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• 2000

The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.

• Journal of the Korean Society of Food Culture
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• v.31 no.5
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• pp.489-497
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• 2016

Kunrak, a type of Korea traditional cheese, is made using Tarak, a yogurt produced with makgeolli as the fermentation source. Kunrak is produced by removing whey from Tarak, followed by drying process for safe storage and consumption over a longer period. In this study, we produced kunrak based on the method described in "Imwonsibyukji". Prepared Kunrak was ripening for 96 hours at 20, 30, and $40^{\circ}C$. In order to study characteristics of Kunrak, physiochemical properties (pH, acidity, water contents) and contents of metabolites (organic acids, sugars, amino acids, and fatty acids) were analyzed. During ripening, water contents decreased. The main organic acids in Kunrak were citric acid and lactic acid, and the main free sugar was lactose. Main amino acids were glutamate and phenylalanine, and main fatty acid was saturated capric acid. At later ripening, all metabolites increased immediately after preparation. The sensory evaluation score of overall preference was highest for Kunrak, which was ripening at $40^{\circ}C$ for 96 hours. This study was aimed to assay metabolites of Kunrak under various ripening conditions. The results provide basic data to produce conditions for standardized manufacturing of Kunrak.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.81-86
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• 2002

A bacteriocin producing lactic acid bacteria was isolated from ground beef and the strain was identified as Lactobacillus plantarum ssp. by use of API carbohydrate fermentation pattern and physiological tests. The bacteriocin produced by L. plantarum KU107 exhibited a good spectrum of activity against foodborne pathogens including Bacillus cereus, Escherichia coli, Listeria ivanovii, Listeria monocytogenes, Pseudomonas aeruginosa, Pseudomonas chlororaphis, Staphylococcus aureus, Staphylococcus intermedius, Salmonella typhimurium and Yersinia enterocolitica. The bacteriocin was active over a wide pH range and stable of heat treatment, and inactivated by treatment with proteases. A bacteriocin from L. plantarum KU107 was effetive in reducing S. aureus in tryptic soy broth. On the ground beef containing S. aureus was added with the crude bacteriocin, S. aureus was inhibited during storage period at 4$\^{C}$.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.92-96
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• 2003

Effects of vitamin C on the properties of bread including number of yeast cells, volume of bread, specific loaf volume, and hardness and sensory characteristics were evaluated. Vitamin C was added at various amounts to frozen doughs made through sponge &dough method using sweet dough formula and quickly frozen at $-40^{\circ}C$. Doughs were stored for 4 weeks at $-20^{\circ}C$. Evaluations were done after frozen dough was thawed, fermented, and baked every week. The bread with 150 ppm vitamin C revealed higher yeast cell survival rate during freezing storage, and higher specific and bread volumes than other doughs. Hardness of bread increased with increasing amount of vitamin C added. Bread with 100 ppm vitamin C revealed the highest sensory score. Consequently, addition of 100 ppm vitamin C to bread dough resulted in the highest overall evaluation.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.55-60
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• 2005

Frozen dough made by sponge and dough method using sweet dough formula was quickly frozen at $-40^{\circ}C$ and stored for 8 weeks at $-20^{\circ}C$. Effects of vital wheat gluten on number of yeast cells, bread volume, specific loaf volume, hardness, and sensory properties of bread were investigated. Dough added with 4% vital wheat gluten showed higher yeast cell survival rate during freeze storage and larger specific loaf volume than other doughs. Hardness value increased with increasing amount of vital wheat gluten added, whereas, in frozen dough stored more than 4 weeks, dough added with 2% vital wheat gluten showed lower hardness value than others. Bread made with 4% vital wheat gluten showed highest sensory score.