• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.95-103
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• 2008

The aim of this study was to evaluate the physicochemical, microbial, and sensory characteristics, as well as antioxidative activities of yoghurts containing spirulina powder, during storage at 4$^{\circ}C$. The pH of the yoghurts decreased until the 9th day of storage, but significantly increased by the 12th day. Total acidity also increased until the 9th day of storage, and then significantly decreased by the 12th day. Sugar content did not change significantly (approximately 18 $^{\circ}Brix$). Viscosity(cP) increased until the 6th day of storage, but had decreased at the 12th day. The viable bacterial cell counts of the control group decreased during storage. In contrast, the viable cell counts of the spirulina containing samples increased until the 9th day, and then decreased by the 12th day of storage. Antioxidant activity decreased in all groups, but the changes in antioxidant activity were lower in the spirulina groups than in the control group. According to sensory evaluations, the samples presented no significant differences during storage. Based on the above results, the optimum concentration of spirulina was determined as 0.25%. Also, the period of circulation of yoghurt containing spirulina was estimated to be 9 days at 4$^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.237-245
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• 2016

In this study, the physicochemical and sensory characteristics of low-salt Myungran jeotkal (Alaskan pollock roe) were evaluated after fermentation at $4^{\circ}C$ and $20^{\circ}C$ with or without the addition of deep sea water, salt from deep sea water, and vegetable-origin lactic acid bacteria (Lactobacillus fermentum JS, LBF). When fermented at $20^{\circ}C$, the addition of LBF to Myungran jeotkal resulted in a slow increase in lactic acid content, followed by an abrupt increase after five days of fermentation. However, when fermented at $4^{\circ}C$, the lactic acid content did not change significantly. Further, when Myungran jeotkal fermented at $4^{\circ}C$, the pH decreased as lactic acid production increased. The salinity of Myungran jeotkal fermented at $4^{\circ}C$ and $20^{\circ}C$ was 7% and was not affected by fermentation period. When fermented at $20^{\circ}C$, volatile basic nitrogen and amino nitrogen contents increased with increasing duration of fermentation. Further, volatile acid content decreased, however, the content of amino nitrogen increased after 11 days of fermentation with LBF and no salt effects were observed. When fermented at $20^{\circ}C$ for 13 days, preference (sensory evaluation) was the highest in all experimental groups after 9 days of fermentation, and then decreased as the fermentation period increased. The free amino acid content was highest (1,648.8 mg/100 g) in Myungran jeotkal when sun-dried salt and LBF were added, 2.3 times higher than in the control.

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.482-489
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• 1996

Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.104-110
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• 2011

This study was conducted to improve the food functional and sensory food quality of Hizikia fusiforme by the fermentation of lactic acid bacteria. Seven strains of lactic acid bacteria isolated from traditional Korean fermented food were inoculated and cultivated in H. fusiforme water extract. Among them, Lactobacillus brevis LB-20, isolated from Kimchi, was selected for further study by considering the results of bacterial growth, DPPH radical scavenging activity, and sensory evaluation. No significant differences in proximate compositions (moisture, crude protein, crude fat, and crude ash) were observed by the fermentation of L. brevis LB-20. The most dramatical change was the conversion from glutamate to ${\gamma}$-aminobutyric acid (GABA) in H. fusiforme water extract fermented by L. brevis LB-20. The GABA content increased approximately 60-fold after 48 hr of fermentation. The bacterial fermentation also resulted in low-molecularization of the extract. The particle size of the fermented extract became approximately 4-fold smaller than that of the law extract. In addition, the analysis of volatile flavor compounds using GC/MS revealed that the bacterial fermentation dramatically removed off-flavors such as acetaldehyde, haxanal, diallyl disulphide and 1-penten-2-ol in the H. fusiforme extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.354-362
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• 1991

To investigate nutritional and biochemical values of buckwheat, amino acids and minerals in buckwheat harvested from Kangweon-do were analysed. Mixed flour between buckwheat and wheat were made to be used for buckwheat noodle and were also analysed minerals and major nutrients in composite flours. When three different levels of flour mix were compared, major nutrients were about same among those mixes but minerals were higher by adding more buckwheat flour, especially by adding more imported buckwheat flour. From this mixed flour, 9 minerals and 16 amino acids including 9 essential amino acids were analysed. Contents of selenium, sodium and magnessium were very high in buckwheat flour, Therefore, nutritional value of domestic buckwheat was highly evaluated. BAP method was used to determine the change of gelatinization in the noodles prepared by extruder at 8$0^{\circ}C$, and in the noodles during freeze drying and refrigeration. 70% of gelatinization was done during noolding process and retrogradation was severe during refrigeration.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.41-50
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• 2008

Purpose: Bone morphogenetic protein-2(BMP-2) has been shown to possess significant osteoinducitve potential. There have been attempts to overcome a limitation of mass production, and economical efficiency of BMP. The aim of this study was to produce recombinant human BMP-2(rhBMP-2) from E. coli in a large scale and evaluate its biological activity. Materials and Methods: The E.coli strain BL21(DE3) was used as a host for rhBMP-2 production. Dimerized rhBMP-2 was purified by affinity chromatography using Heparin column. To determine the physicochemical properties of the rhBMP-2 expressed in E. coli, we examined the HPLC profile and performed Western blot analysis. The effect of the purified rhBMP-2 dimer on osteoblast differentiation was examined by alkaline phosphatase (ALP) activity and representing morphological change using C2C12 cell. Results: E. coli was genetically engineered to produce rhBMP-2 in a non-active aggregated form. We have established a method which involves refolding and purifying a folded rhBMP-2 dimer from non-active aggregates. The purified rhBMP-2 homodimer was characterized by SDS-PAGE as molecular weight of about 28kDa and eluted at 34% acetonitrile, 13.27 min(retention time) in the HPLC profile and detected at Western blot. The purified rhBMP-2 dimer stimulated ALP activity and induced the transformation from myogenic differentiation to osteogenic differentiation. Conclusion: rhBMP-2 was produced in E. coli using genetic engineering. The purified rhBMP-2 dimer stimulated ALP activity and induced the osteogenic differentiation of C2C12 cells.

• The Journal of Natural Sciences
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• v.4
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• pp.69-83
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• 1991

To determine optimum ethanol concentration and clarification time in ethanol clarification of red ginseng extract(RG-Ext), physical properties, crude saponin recovery of clarified RG-Ext. and stability of red ginseng drink prepared from clarified RG-Ext. were investigated. Color intensity, redness(a value), viscosity and yield of clarified RG-Ext. were decreased in proportion to the increase of ethanol concentration and clarification time, but transmittance, brightness(L value) and yellowness (b value) were decreased. Crude saponin recovery of clarified RG-Ext. were not change significantly by the increase of ethanol concentration. Red ginseng drink prepared from 50-90% ethanol clarified RG-Ext. were stable without precipitation until six months at the storage of $0-5^\circC$ and $40^\circC$.

• Food Science and Preservation
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• v.14 no.4
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• pp.394-399
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• 2007

In this study, the characteristic qualities of whole soymilk were examined based on differing hydrolysis condition. The results showed that as the concentration of enzyme preparation(KMF-G) increase, $^{\circ}Brix$, calcium-binding capacity, and the content of free amino acid components also increased. Additionally SDS-PAGE analysis revealed a similar pattern of in the molecular weight of proteins at enzyme preparation concentration 0.20 and 0.35%(w/w). The quality of whole soymilk hydrolysate was shown to be best at a enzyme preparation(KMF-G) concentration of 0.20%(w/w) and hydrolysis time of 60 min. When sterilized at 115, 130 and $145\;^{\circ}C$ for 15 sec each the change in whole soymilk quality was not substantial. Based on the above results, a 0.20%(w/w) enzyme preparation(KMF-G) concentration and 60 mim hydrolysis time was determined to be the optimal hydrolysis condition for whole soymilk. It is anticipated that soymilk hydrolysis will a food material that is diverse in its application and uses.

• Food Science and Preservation
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• v.18 no.4
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• pp.436-441
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• 2011

The change in physicochemical and sensory properties and bioactive compounds of Campbell grape juice has been investigated for 30 days at $-5^{\circ}C$. The pH and sugar/acid ratio of the cold stabilized juice increased, while titratable acidity and soluble solids decreased as cold stabilization period is prolonged. Juice samples became lighter, yellowish to brownish and lesser red in color as can be observed with the increasing $L^*$ and $b^*$ values, and decreasing $a^*$ value, respectively. The juice cold stabilized for a shorter period of time showed higher levels of bioactive compounds and radical scavenging activity, and was more preferred by the panelists than the juice cold stabilized for a longer period of time. These results suggest that cold stabilization period affected the quality characteristics of grape juice.