• The Korean Journal of Mycology
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• v.39 no.2
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• pp.151-153
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• 2011

In order to optimize storage conditions of Korean traditional Makgeolli, we brewed Korean traditional Makgeolli for 1 week with two-stage fermentations and investigated changes viable cell counts of yeasts and bacteria during storage for 1 month at $4^{\circ}C$ and $20^{\circ}C$. Yeast viable cell counts were decreased to 89.0% after storage for 30 days at $20^{\circ}C$, however, those were not significantly changed at $4^{\circ}C$ storage. Bacteria cell counts were decreased to 59.0% of initial cell counts for 30 days at $4^{\circ}C$. In the storage at $20^{\circ}C$, bacteria were significantly decreased to 98.0% of initial cell counts after storage for 30 days. Lactic acid bacteria were also similar to those of total bacteria cell counts at $4^{\circ}C$ storage, however, 99% of lactic acid bacteria were decreased at $20^{\circ}C$ storage for 30 days.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.48-52
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• 2007

Yogurt base was prepared from skim milk supplemented with 0.2-1.0% (w/v) garlic powder and fermented with lactic acid bacteria (the mixed strain of Lactobacillus acidophilus, Bifidobacterium longum and Streptococcus thermophilus) at 40$^{\circ}C$ for 18 h. Quality characteristics of the prepared yogurt were evaluated for acid production (pH and titratable acidity), number of viable cells, viscosity and sensory properties. The addition of garlic powder inhibited the growth of lactic acid bacteria and decreased the acid production. After 18 h incubation, titratable acidity of garlic yogurt was 1.28-1.08% and was lower than that (1.35%) of yogurt made with only skim milk. However, the viscosity of yogurt was remarkably increased by the addition of garlic powder. The sensory score of yogurt added with 0.2% garlic powder was similar to ordinary yogurt in flavor and overall acceptability. According to sensory score and fermentation characteristics, the optimum concentration of garlic powder was around 0.2%.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.97-102
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• 2021

In this study, enzymes were screened for hydrolysis of defatted perilla seed residue (DPSR) and optimal conditions for enzymatic treatment were determined to produce the hydrolysate of DPSR. Also its antioxidant activity and utilization as a culture medium were examined. The combined treatment of Alcalase and Ceremix is most effective for solubilization of protein and carbohydrate in DPSR. The optimal dosage, pH, and reaction time for enzymatic treatment were found to be 2.0% (w/w), 7.0, and 2 h, respectively. Treatment with optimal conditions of enzymes dramatically increased reducing sugar, soluble protein, and total phenolic content. The hydrolysate of DPSR possessed better scavenging activity against cation and free radicals than enzyme-untreated extract. When Leuconostoc mesenteroides 310-12 was cultured in the hydrolysate of DPSR, cell population rapidly increased compared to enzyme-untreated extract, and titratable acidity increased in proportion to the bacterial growth. In conclusion, these results imply that the hydrolysate of DPSR could be utilized as a bacteria culture medium as well as a physiologically active material with antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.681-687
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• 2007

This study was designed to examine the suitable characteristics of potential probiotic bacteria. Possible probiotic bacteria, including Lactobacillus acidophilus DDS-1, Lb. acidophilus B-3208, Bifidobacterium bifidum KCTC 3357, Lb. plantarum, Leuconostoc mesenteroides ssp. mesenteroides ATCC 8293, and Lactococcus lactis ssp. lactis ATCC 7962 were selected. We then measured their acid and bile tolerances, adhesion properties in the gastrointestinal tract, antimicrobial activity against pathogenic bacteria, and immunomodulation activity. The acid tolerances of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, Lb. plantarum, and Leu. mesenteroides ssp. mesenteroides ATCC 8293, in PBS (pH 2.5) for 2 hr, were high enough that 50% of the inocula survived. The bile tolerances of all bacteria, except Lc. lactis ssp. lactis ATCC 7962, were also observed at a 3% oxgall concentration in MRS broth. The results of the adhesion property assay showed that the total binding affinities of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, and B. bifidum were about three times higher than those of the other bacteria. In testing their antimicrobial activities against pathogens, Lb. acidophilus B-3208, B. bifidum KCTC 3357, and Lb. plantarum inhibited the growth of pathogenic bacteria. For their immunomodulation activity, the cell wall fractions from Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 showed the highest bone marrow cell proliferation activities. However, the cell wall fractions of Lb. acidophilus DDS-1 and B. bifidum, and the cytosol fraction of Lc. lactis ssp. lactis ATCC 7962 showed higher macrophage stimulation activities than those of the other bacteria. Since Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 satisfy the requirements for probiotics, they can be considered suitable probiotic bacteria.

• Food Science and Preservation
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• v.19 no.6
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• pp.933-938
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• 2012

The quality characteristics of rice wine seed mash and rice wine made with different lactic acid concentrations were investigated. The pH decreased along with the lactic acid concentration. The total titratable acid content of the rice wine seed mash was lowest when 0.5% lactic acid was added, and the ethanol contents of the mash samples were not significant. The results of the measurement of the microorganism number, C (cell numbers of the total bacteria and the lactic acid bacteria), decreased along with the lactic acid concentrations of the mash samples. The yeast cell numbers of the rice wine seed mash samples according to the lactic acid concentrations were high (0.5, 0.3, 1.0, control, and 0.7%, respectively). The pH and total titratable acid levels of rice wine according to the lactic acid concentration were stable during fermentation, according to the increase in the amount of lactic acid. The organic acids in the rice wines were highest in the lactic acid. The rice wines to which lactic acid had been added had lower acetic acid contents than the control. Also, the acetic acid contents decreased along with the lactic acid concentrations, except in the rice wine treated with 1.0% lactic acid. The ethanol contents of the tested rice wines were not significant. All in all, in the sensory evaluation, the rice wines treated with 0.5 and 0.7% lactic acid scored higher than the other treatments.

• Food Science and Preservation
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• v.24 no.2
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• pp.274-281
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• 2017

The optimization of lactic acid fermentation was conducted to produce an old antler fortified with functional ingredients. For the over-production of gamma aminobutyric acid (GABA), the extract of old antlers (OA) was fermented by Lactobacillus plantarum EJ2015 with 0.5% YE, 1.5% glucose, and 3.5% MSG at $30^{\circ}C$ for 7 days. The lactic acid fermented OA showed high viable cell counts of $2.0{\times}10^8CFU/mL$, pH 6.56 and 0.77% acidity after 7 days. Addition of Auricularia auricula-judae (AAJ) enhanced the cell growth of L. plantarum EJ2014, resulting in higher viable cell counts of $2.0{\times}10^9CFU/mL$ and acid production after fermentation for 1 day. In particular, acidity was greatly decreased after fermentation for 3 days and 1.4% GABA was produced by converting efficiently mono sodium glutamate as a substrate. Fermented OA/AAJ mixture indicated the reduced cytotoxicity compared with that of unfermented OA. The fermented OA/AAJ mixture indicated anti-inflammatory effect with less production of NO in microphage cells. The production of NO dropped to $17.75{\mu}M$ at 4 mg/mL, and to $5.58{\mu}M$ at 6 mg/mL old antler after fermentation. Thus, lactic acid fermented OA with AAJ could fortify GABA, probiotics and dietary fiber.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.340-344
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• 1993

Gel type yoghurts from 5 representative manufacturers were collected at market and evaluated their physico-chemical properties during storage at $5^{\circ}C$. The range of pH, acidity, Brix and viscosity of each product were $3.87{\sim}4.19,\;0.97{\sim}1.42%,\;16.2{\sim}22.2\;and\;7,850{\sim}21,000 cp$ respectively. The pH of each product decreased gradually during storage time and reached around pH 4.1 after 16 days with proportional acidity increasing. The viscosity of all test products showed increasing trend by lactic acid bacterial action. Total lactic acid bacteria were $10^8{\sim}10^9\;CFU/ml$ at the beginning storage and increased or decreased depending upon each product. But all product maintained over than $10^8 CFU/ml$ which meets regulatory level after 16 days storage.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.948-956
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• 1998

This study aimed to investigate of Andong sikhe by using pure culture inoculation technique and the improvement of storage stability by the addition of stabilizers to the product. Microorganisms were selected for the pure culture inoculation in the fermentation. The changes in chemical composition such as total acidity, sugar content, amino acid and various forms of nitrogen during fermentation were determined. The changes in pH of the product, the enzyme activities and the population of lactic acid bacteria and yeast were also followed in the process of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.450-456
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• 2013

This study evaluated the quality characteristics of fermented abalone-kimchi or sea tangle-kimchi during 28 days of storage at $4^{\circ}C$. Abalone and sea tangle were added as extracts compared to a control. We analyzed lactic acid bacteria, pH, acidity, salinity, reducing sugars, free sugars, organic acids, free amino acids, and sensory characteristics. The lactic acid bacteria levels were 4.4~5.3 log CFU/g on day 0, 6.8~7.1 log CFU/g after 7 days, and continued to rise during the fermentation period. The salinity increased slightly over time. As fermentation progressed, pH and reducing sugars, free sugars, and organic acid contents decreased. Free sugars, in particular, dramatically decreased about 70% compared to the initial day. The total free amino acid content was higher in abalone-kimchi. In terms of free amino acid contents, taurine was high in abalone-kimchi, while glutamic acid and aspartic acid content was high in sea tangle-kimchi. The sensory evaluation results show that abalone-kimchi and sea tangle-kimchi had higher scores for their savory taste and overall acceptance compared to the control.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.57-63
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• 1971

1) Among five lactic acid bacteria examined, Str. thermophilus and Str. diacetilactis produced remarkably greater amount of acids in soybean milk than Str. lactis, Str. cremoris and L. bulgaricus. 2) Soybean milk and skimmed dry milk were combined in the ratio of 7 : 3 and were carried out in lactic acid fermentation for 24 hours at optimum temperature. The result indicated that the yield of precipitation and protein content of it were the most, the moisture content was the least and curd structure formed was considered too hard. 3) Based on these and other results, following procedure was used for manufacturing: soybean milk and skimmed dry milk were combined in the ratio of 7 : 3, heated at $121^{\circ}C$ for 20 min., cooled, added Str. thermophilus as lactic acid starter and incubated for 24 hours and $37{\pm}1^{\circ}C$. The curd was cooked, hooped, and pressed for 24 hours, to the surface of which, Penicillium caseicolum and sodium chloride were spread. During ripening of the curd at $15^{\circ}C$ and $85{\sim}90%$ RH for 21 days, Pen. caseicolum was highly developed after 7 days, pH was increased and proteolytie activity has reached to the peak point after 14 days. After 7 days of ripening total water soluble nitrogen, water soluble protein nitrogen and amino acids nitrogen were begun to increase. After 21 days of ripening total water soluble nitrogen, water soluble protein nitrogen and amino-N reached to 52%, 32% and 14% of total nitogen. In the soybean cheese, after 21 days of ripening, 17 or more kinds of amino acids were detected by two-dimentional paper chromatography. The product contained 63.2% of moisture, 17.5% of crude protein, 13.2% of crude fat, 2.8% of crude ash and 2.5% of sodium chloride.