• Microbiology and Biotechnology Letters
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• v.13 no.2
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• pp.151-156
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• 1985

To investigate the new Yoghurt starter, Lactobacillus helveticus YM-1, which was selected among 14 Lactobacillus strains, and Streptococcus thermophilus CH-1 were inoculated together in reconstituted non-fat skim milk medium and their growth characteristics and cultural conditions for the mixed culture were examined. The main results of this study were obtained as follows. The typical symbiotic growth was shown between the two strains and pH and temperature for optimal growth were 6.5 and 4$0^{\circ}C$, respectively. Heat treatment of milk was most effective at 10$0^{\circ}C$ for 30 min. The cell-free filtrate of Lactobacillus helveticus YM-1 had stimulatory effect on Streptococcus thermophilus CH-1 but the reverse case was slightly observed. Significant difference was observed in the proteolytic activities between Lactobacillus helveticus YM-1 and Streptococcus thermophilus CH-1. The former liberated 135$\mu\textrm{g}$ free amino acid per $m\ell$ of cultured milk, the latter 35$\mu\textrm{g}$ per $m\ell$.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.50-53
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• 1996

A cultured milk product was made by fennenting 10$\%$ reconstituted skim milk with Lactococcus lactis subsp. lactis TA29 and Saccharomyces exiguus SK2. L. lactis TA29 and S. exiguus SK2 grew up to 1.0 $\times 10^9\;and\;2.0 \times 10^6$ cfu/ml, respectively. After the fermentation 21$\%$ of lactose was hydrolyzed, pH was lowered to 4.2, and titratable acidity and alcohol concentration were increased to 0.96 and 0.023$\%$, respectively. When the fermented milk was stored at $4{\circ}C$ for 9 days, the viable cell counts for L. lactis TA29 and S. exiguus SK2 were $6.5 \times 10^5\;and\;1.6 \times 10^6$ cfu/rnl, respectively. The alcoholic fermented milk prepared in this experiment was more inhibitory against some pathogenic bacteria including C. perfringens than commercial yoghurt products tested.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.815-822
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• 1993

This experiment was carried out to determine the separation condition of 1-dimethylaminonaphthalene-5-sulfony(Dansyl) derivatives of amino acids by reverse-phase high performance liquid chromatography with Nova-Pak C18 column. Determined solvent system was solvent A(200mA phosphate buffer pH 6.8 15%, acetonitrile 11%, water 74%) and solvent B(acetonitrile 65%, methanol 28%, water 7%). Linear gradient of solvent B was applied from 12% to 80% for 50min. Complete separation of 20 amino acids including asparagine and glutamine which constitute protein was achieved within 50min. As the detection limit was the range of picomole, the resolution power was excellent. Reproducibility of the retention time was less than mean $\pm$0.05min. According to the above optimum chromatographic conditions, the amino acid composition of some food and human blood was examined. The most affluent amino acid was alanine in human blood, aspartic acid and glutamic acid in soy sauce, alanine and threonine in soy milk and proline in milk and yoghurt.

• Korean Journal of Community Nutrition
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• v.7 no.5
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• pp.715-723
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• 2002

In recent yearn, eating habit that is not right causes disease the dietary fiber (DF) intakes of Korean decreases. Occurrence of chronic disease such as constipation increased gradually. This study was performed to investigate of high fiber standard recipes for one day including major source of DF such as vegetables, cereals and grain products, seaweeds, fruits, fungi and mushrooms, and legumes and products for improving constipation through dietary treatment. Nutrient analysis per person marked energy, protein, fat and DF content. The food of high I : S ratio (Insoluble fibers: Soluble fibers) are soybean sprout salad, rice gruel with vegetables, pan fried mushroom with vegetables. The food of low I:S ratio are fermented soybean paste stew, fried rice with kimchi, fruits salad with yogurt dressing and seasoned noodle with vegetables. The representative high fiber diet menu is rice gruel with vegetable, rice with radish and oyster, fermented soybean paste stew, kimchi stew, assorted soybean sprout salad, three kinds of pancake roll, pan fried mushroom with vegetables, fruits salad with yogurt dressing and seasoned noodle with vegetables. The menu developed in this study, contains fiber of at least 8.97 times of RDA and in point view of 1 day intake, that is similar to the scope of RDA, 20-25 g per day. This findings should be appliable to nutritional education and medical food for constipation. And also, the aim of study is constipation patients easily applicate that developed the food of high fiber using Korean common food. And the result of the study will be the basic data about clinical test of food developed in this study and the danger of high fiber diet. The representative high fiber diet menu is rice gruel with vegetable, rice with radish and oyster, fermented soybean paste stew, kimchi stew, assorted soybean sprout salad, three kinds of pancake roll, pan fried mushroom with vegetables, fruits salad with yoghurt dressing and seasoned noodle with vegetables. This findings should be applicable to nutritional education and medical food for constipation.

• Journal of Dairy Science and Biotechnology
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• v.35 no.1
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• pp.33-38
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• 2017

This study was conducted to investigate the fermentation forms of goat milk, and the changes in the flavor of goat milk fermented using single and mixed strains of commercial Lactobacilli during storage. The mixed strains reached a lower pH more quickly than the single strains. The mixed strains also had higher rates of Lactobacillus proliferation. The tastes detected in sensory tests can differ depending on the skill levels of the panel, making it difficult to obtain reproducible and objective data when numerous samples are analyzed. Therefore, we measured changes in flavor during storage using taste sensors. The taste sensors measured diverse flavor changes in goat milk fermented using single strains and mixed strains. Notably, this study is the first in our country to measure changes in the taste and composition of fermented milk during cold storage using taste sensors. This work could have great value for the maintenance and monitoring of dairy products within their expiration dates.

• Food Science of Animal Resources
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• v.29 no.5
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• pp.647-652
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• 2009

A duplex PCR technique was applied for specific identification of cow and goat milk in milk products by using primers targeting the mitochondrial 12S rRNA gene. Duplex PCR using primers specific for cow and goat generated specific fragments of 223bp and 326bp from cow and goat milk DNA, respectively. Duplex PCR was applied to 15 milk products purchased from the market to verify label statements. The labeling statements of four market milk products, three yoghurt products, and one whole milk powder product were confirmed in the duplex PCR. The labeling statements of five of seven infant milk powder products were also confirmed by duplex PCR but the other two products were shown to be contaminated with either cow or goat milk. The proposed duplex PCR provides a rapid and sensitive approach to detection of as little as 0.1% cow milk in goat milk and one-step detection of cow or goat milk in milk products.

• Journal of Dairy Science and Biotechnology
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• v.24 no.1
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• pp.1-7
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• 2006

This experiment was performed to identify the improvement of raw milk quality after introducing raw milk grading system(1993, June). The purpose of this experiment was to investigate chemical component and microbiological quality of raw milk in jeju. This experiment made it possible to spread high standard of quality of raw milk or milk product including yoghurt, ice cream etc., and to provide dairy industry information for the construction of Jeju international free city master plan. As a result, automatic milking system is improved a lot after introducing raw milk grading system and sustained good condition compared with other provinces. High ratio was shown dairy farm in jeju for pre-milking, pre-cooling system equipment and self laboring. Otherwise, the ratio of dairy farm doing test of mastitis is low. The ratio of first grade distribution in Jeju is 80.64%, which means that was improved before introducing raw milk grading system. The number of somatic cells found in summer more than that of other seasons in raw milk. However, these data is a little higher than the nation wide data medium. Also, general components, annual lipid ratio is 3.90% that improved compared with before introducing raw milk grading system. These data showed low in summer and similar to nation wide.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.153-160
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• 2010

The present study was carried out for the isolation of bacteriocin-producing enterococci from indigenous sources. Gram-positive enterococci are known for having the ability to produce enterocins with good antimicrobial potential. A total of 34 strains were isolated from processed dairy products of Pakistan and seven out of them were found to be member of genus Enterococcus on selective enumeration. Biochemical and molecular characterization revealed that four of these isolates (IJ-03, IJ-07, IJ-11, and IJ-12) were Enterococcus faecalis and three (IJ-06, IJ-21, and IJ-31) were Enterococcus faecium. Local processed cheese was the source of all enterococcal isolates, except E. faecium IJ-21 and IJ-31, which were isolated from indigenous yoghurt and butter samples, respectively. Bacterial isolates were sensitive to commonly used antibiotics except methicillin and kanamycin. They also lacked critical virulence determinants, mainly cytolysin (cyl), gelatinase (gel), enterococcal surface protein (esp), and vancomycin resistance (vanA and vanB). Polymerase chain reaction amplification identified that enterocin A and P genes were present in the genome of E. faecium IJ-06 and IJ-21, whereas the E. faecium IJ-31 genome showed only enterocin P genes. No amplification was observed for genes that corresponded with the enterocins 31, AS-48, L50A, and L50B, and ent 1071A and 1071B. There were no signals of amplification found for E. faecalis IJ-11, indicating that the antimicrobial activity was because of an enterocin different from those checked by PCR. Hence, the indigenous bacterial isolates have great potential for bacteriocin production and they had antibacterial activity against a variety of closely related species.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.376-385
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• 2011

The purpose of this study was to estimate beverage consumption frequency and determine related problems of elementary school students in Chungnam. The survey was conducted with 488 students(boys=230, girls=258) using a questionnaire. The average age of the students was 10.1 years old, thir average height and weight were 145.1 cm and 39.5 kg, respectively and the obesity index was -1.3%. The frequencies for breakfast, lunch and dinner were 5.8 times/week, 6.7 times/week and 6.4 times/week, respectively. Regarding the frequency of snacks, high response rates for 'once/day'(38.3%) and 'none' (30.5%) were observed. Nutrition label on beverages were identified rarely(39.1%), nearly never(19.7%), and never(12.9%). The choice factors in selecting beverage were taste, nutrition, and price. For the type of snack most often consumed, fruit or juice was 25.8%, snack items were 25.2%, bread was 24.8%, dairy products were 7.6%, beverages were 7.0%, noddles were 6.2%, and rice cakes were 3.5%. The kinds of favorite beverages were carbonated drinks(30.3%), functional drinks (24.4%) and milk and yoghurt(23.8%), and main reason for the choice of beverage was "it tastes good". For the point of time that students wanted to drink a beverage, "when I feel thirsty" appeared most often for dairy products and beverages and the next most frequent answer was "after exercise". Therefore it may be necessary to administer systematic nutritional education on perception on nutrition fact label of beverage. And it is thought that plan for proper beverage consumption in elementary school students may be established.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.968-976
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• 2007

This experiment was carried out to investigate the effects of spirulina powder on the growth properties of lactic acid bacteria in reconstituted skim milk. The spirulina powder supplemented to S. thermophilus and L acidophilus slightly stimulated lactic acid production. In addition, the growth and acid production of L. bulgaricus were enhanced by the addition of spirulina powder. When the spirulina powder was added to reconstituted skim milk at the level of 1%, the mixed cultures of S. thermophilus and L. bulgaricus showed higher numbers of viable cells and higher acid production than the other cultures. The effects of the addition amounts of spirulina powder (1%, 2% and 3%) to the reconstituted skim milk on the growth properties of the mixed cultures of S. thermophilus and L. bulgaricus were evaluated. The pH of the skim milk with added spirulina powder was lower than that of the control, but the amount of spirulina did not have a significant affect. The titratable acidity increased with the incubation time until 12 hr. The number of viable cells in the skim milk with added spirulina increased according to the amount of spirulina. Thus, the spirulina was effective for the increasing lactic acid bacteria in yoghurt.