• Korean Journal of Food Science and Technology
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• v.4 no.3
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• pp.200-205
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• 1972

Effects of several different petroleum fractions (LGO, HGO, VGO, Diesel oil, SP(E), HGO-wax, L/M-wax), stepwise addition of calculated amounts of HGO at defined intervals, recycling of spent media on cell growth of Candida tropicalis KIST 351 were studied using $2.5{\ell}$ fermenter by batch process. In addition, continuous cultivation of the yeast was also performed in the light of biomass production using $28{\ell}$ fermenter with LGO. 1) Cell concentration, yield on the basis of gas oil and n-paraffin with the petroleum fractions were in the range of $11{\sim}15g/{\ell}$, $10{\sim}12%$ and $77{\sim}82%$, respectively. 2) By stepwise addition of the gas oil, cell concentration and yield on the oil were increased up to 18.9 g/land 13%, respectively. 3) Spent medium slowed emulsifying ability of hydrocarbon and stimulating effect on the cell growth. Without additional supplementation of $Mg^{++}$ up to 20% of spent medium could be reused, while by adding of the $Mg^{++}$, 50% of medium could be recycled. 4) Optimum condition of continuous cultivation for biomass production was attained at the dilution rate of $D=0.1{\sim}0.125\;hr^{-1}$. Maximum yield coefficient on consumed n-paraffin was 0.94 at $D=0.1\;hr^{-1}$, however, 24% of supplied n-paraffin in the media was not utilized at this dilution rate.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.751-756
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• 2002

For the development of functional jang-products, kanjang was prepared using barley bran. Optical density of barley bran kanjang was significantly high at 15 days after fermentation, and the amount of extract was $2{\sim}3$ fold higher than that of soybean kanjang. Among the flavor components identified in barley bran kanjang, the content of 2-furancarboxaldehyde was the highest, followed by 4-vinyl-2-methoxy-phenol, benzene-acetaldehyde, palmitic acid, and methyl-9,12-octadecadienoate. In barley bran and soybean mixtare (1 : 1) kanjang, the content of 2-furancarboxaldehyde was the highest, followed by benzeneacetaldehyde, diethyl phtalate, palmitic acid, and 2-chloroethyl linoleate. Flavor components detected in both barley bran kanjang and barey bran and soybean mixture kanjang were 2-furancarboxaldehyde, benzaldehyde, benzeneacetaldthyde, 4-vinyl-2-mehtoxy-phenol, 1-furfuryl-2-formy pyrrole, dimethyl-1,2-benzenedicarboxylate, diethyl phtalate, palmiticacid, dibutyl-1,2-benzenedicarboxylate, and di-(2-ethylhexyl)phthalate.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.260-266
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• 1996

This study was carried out to investigate the bacterial microflora of commercial and traditional Kochujang. Computer aided idetification systems were used to identify the bacteria in Kochujang. Seven genera such as Bacillus, Corynebacterium, Enterococcus, pasteurella, Pseudomonas, Staphylococcus and Streptococcus in commercial process and 10 genera such as Bacillus, Corynebacterium, Enterococcus, Flavimonas, Flavobacterium, Gemella, Pasteurella, Pseudomonas, Staphylococcus and Streptococcus in traditional process were identified. Distribution of genus Bacillus was $56{\sim}70%$ during fermentation in the commercial process and $38{\sim}50%$ in the traditional process. B. lichenoformis strains identified in this study were classified into three types by their physiological characteristics.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.588-594
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• 1997

Yeast strains useful for the production of wine using mandarine orange, Citrus unshiu, as a main substrate were screened, and their primary ability to decompose citric acid that affects directly wine quality was investigated. Total eleven strains were selected for brewing orange wine. Five wild strains were from soil-based collections and identified: four of them were Saccharomyces cerevisiae and one of them was S. ellipsoideus. The rest of six strains were from among eighteen laboratory strains: three of them were S. cerevisiae, and the other three were S. coreanus, S. uvarum, and S. sake. Two strains of S. cerevisiae out of these selections were chosen and their decomposition of citric acid was investigated. Citric acid was not utilized as sole carbon source for cellular growth. However, when both citric acid and glucose were added together as carbon sources, decrease of citric acid concentration was observed after incubation. Shaking incubation was more effective for the reduction of citric acid than standing incubation. Utilization of citric acid did not contribute to the increase of ethanol concentration during fermentation. On the other hand, it appeared that citric acid caused partial inhibition of cellular growth of the yeasts.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.539-545
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• 1997

Lactobacillus bulgaricus and Kluyveromyces lactis were inoculated to Jangyeob and Jinpum soy milks together after the addition of different amounts of lactose to increase the contents of oligosaccharides, which were compared with single cultured samples. The contents of stachyose, raffinose, sucrose, and glucose of samples without lactose decreased by single culture method, but the oligosaccharides decreased less than in single cultured samples containing of lactose. The oligosaccharides of single cultured samples were equal or decreased compared with soy milks. While those of mixed cultured Jangyeob and Jinpum samples containing 2% lactose for 24 hr incubation increased 125.0% and 118.1%, respectively and those of samples for 36 hr incubation increased 127.0% and 141.0%, respectively, those of mixed cultured samples containing 4% lactose for 24 hr incubation increased 112.5% and 123.0%, respectively and those of samples for 36 hr incubation increased 120% and 135.9%, respectively. Therefore, the oligosaccharides in samples containing 2% lactose were slightly more than in samples containing 4% lactose. Among the cultured methods, oligosaccharides were produced in the largest amounts by the mixed culture for 36 hr. The addition of lactose in soy milks for soy yogurts was effective in the formation of oligosaccharides since the galactose, produced by the hydrolysis of lactose, was thought to be combined with sucrose by the action of ${\beta}-galactosidase$ in yeast.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.662-667
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• 2001

Some biological activities and isoflavone (daidzein, genisten) contents were investigated from chungkugjang (CK) fermented with black beans and Bacillus strains at 42$^{\circ}C$ for 72 hr. n antibacterial activity, black bean CK fermented with Bacillus megaterium SMY-212 was higher than that ferment4d with B. subtilis. In both CK the methanol extract fo large black bean CK was more effective than that of small black bean CK was more effective than that of small black bean. Hydrogen-donating activity of methanol extract of chungjugjang (MEC) prepared with large and small black soybean showed to be 76.4 and 75.5%, respectively. Hydrogen-donating activity of MEC prepared with B. subtilis and SMY-212 was slightly highter than that without both strains. MEC of large black bean was higher in nitrite-scavenging activity than that of small black bean, and black bean CKs fermented with B. subtilis and SMY-212 have no difference in nitrite-scavenging activity B. subtilis and SMY-212. MEC of black bean showed strong antioxidative activity against peroxidation of linoleic acid and $H_2O$$_2$-FeSO$_4$-induced peroxidation of rat liver homogenate. MEC of black bean with Bacillus strains was higher in antioxidative activities than that of black bean without Bacillus strains. Contents of isoflavone (daidzein, genistein) were gradually increased during fermentation of CK. The isoflavone content was slightly higher in large black bean CK than in small black bean CK.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.408-413
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• 2005

Rheological properties and sensory characteristics of prickly pear jelly made from κ-carrageenan and glucomannan were examined. Prickly pear extract (PPE) fermented by Lactobacillus casei LS (isolated from soy milk curd residue) exhibited pH 3.12, 1.15% acidity (lactic acid) and 2.7 × 10/sup 9/ CFU/mL lactic acid bacteria. In the effect of concentration of fermented PPE, the jelly containing 4% fermented PPE had higher springiness and slightly lower hardness than that without fermented PPE, and was superior to color and taste. The hardness and brittleness of jellies were enhanced by the addition of 0.25% citric acid. The addition of 0.25% ascorbic acid resulted in the production of soft jelly like pudding. In the effect of concentration of κ-carrageenan, the hardness and springiness of jellies were increased by adding 0.75% κ-carrageenan, but was decreased by adding at the 0.9% level. In the overall preference of jellies including sweet and sour taste, higher score was obtained by the fortification of 0.6% and 0.75% κ-carrageenan, 0.25% citric acid and 30% fructose syrup.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1239-1244
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• 2003

Microcapsules were prepared by coacervation method using acetone/liquid paraffin system to control the ripening of kimchi. Eudragit E100, which was soluble at below pH 5.0 in aqueous solution, was used to make microcapsules to be sensitive to acidity of kimchi. The microcapsules with Eudragit E100 containing grapefruit seed extract (GFSE) showed the highest yield of 92.13%, the size of microcapsules was decreasing as increasing the amount of aluminium stearate, a dispersing agent. Morphology of the microcapsules determined by scanning electron microscopy showed spherical forms. GFSE, encapsulated antimicrobial agents, was quickly released at acidic buffer (pH 4,5,6) within 1 storage day. However, 70% of encapsulated GFSE in Eudragit E100 microcapsules was continuously released at pH 7 till 3 days, and it was sustained till 9 days. Characteristics of kimchi containing microcapsules of GFSE were analysed with ripening period. Decease of pH in kimchi was retarded with the added GFSE microcapsules till 2 days of fermentation, but GFSE did not affect pH in kimchi after 3 days. Total numbers of microorganisms and lactic acid microorganisms in kimchi were decreased with increasing the amount of the added GFSE microcapsules, however, the effect of controlled released GFSE from pH sensitive Eudragit E100 microcapsules was hard to detect. These results suggest the possibility of pH sensitive microcapsules for high qualify of kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1206-1213
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• 2003

In order to use nutraceutical components in Yulmoo (Coix lachryma-jobi L. var. ma-yuen Stapf), the acceptability of Yulmoo for Takju (Korean rice wine) was examined in terms of the production of volatile components. When Yulmoo was added to the Takju made by commercial koji as a substitute of starch at 0 (rice 100%), 15, 30, 60, and 100%, the ethanol content slightly increased to 13.6, 15.2, 15.2, 14.1, and 13.8%, the Production of isobutanol and iso-imyl alcohol increased as the amount of Yulmoo increased. While the use of Yulmoo to the Takju as the nuruk (Korean traditional koji), inoculated with Aspergillus kawachii (AK) and Rhizopu japonicus (RJ), decreased the contents of n-propanol, iso-butanol, and iso-amyl alcohol as well as the contents of ethanol from 14.3% to 11.2 [AK], 7.5 [RJ], and 10.4% [AK + RJ]. The Yulmoo nuruk in Takju increased the production of acetaldehyde and ethyl acetate indicating the negative effect in the organoleptic evaluation. It was determined that the addition of Yulmoo as a starch source or as nuruk has a critical effect on the production of fusel oils and other volatile compounds in Takju fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.559-564
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• 1991

Three different fermentation methods of dongchimi, a Korean radish roots pickle, were compared with conventional method of brining in 7% NaCl solution at $25^{\circ}C$ in order to improve the storage stability. The methods studied were addition of KCI and $CaCl_2 into the hot ($90^{\circ}C$) salt solutin (method A), addition of salts mixture of phosphates (method B) and salts mixture of phosphates, nitrite and citrate (method C) into half fermented dongchimi solution (pH 4.5~4.7) prepared by the method A. It was found from results that the method B and C reduced the decreasing rate of pH very significantly by more than 2~2.5 folds, while total a measured higher values for the method B and C. Changes in hardness of dongchimi showed little diffeence to control. The concentration of reducing sugar in the first day dongchimi solution prepared by hot brining method was measured much higher than those of control which was followed by rapid decrease. Organoleptic comparion showed a clear effect of salts mixtures by receiving the significantly higher scores in fresh dongchimi flavor and lower values in yeast moldy and sour flavor for the method B and C when those were compared to control.