• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.74-83
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• 2016

In order to improve the sour taste and foul odor of fermented soymilk, bacteria were isolated from kimchi and identified. Of the 89 bacterial strains isolated from kimchi, 3 isolates produced fermented soymilk with a sour taste and foul odor. The selected bacterial strains R53, R83, and R84 were identified by morphological, biochemical, and 16S rRNA analyses as Weissella koreensis. The strain R83, which produced fermented soymilk having the mildest sour taste and foul odor, was selected for further investigation and named W. koreensis KO3. The optimum culture condition for the fermentation of soymilk by W. koreensis KO3 was at $30^{\circ}C$ for 12 h. When soymilk was fermented under the optimum culture conditions, the viable cell count reached up to $8.71{\times}10^8CFU/ml$ and pH and acidity reached as low as 6.02 and as high as 0.33%, respectively. Twenty-seven amino acids and their derivatives were detected in fermented soymilk. The amounts of serine, glycine, threonine, alanine, and aspartic acid, which contribute to a sweeter taste, increased during fermentation. Orinithine, which was not detected before fermentation, increased during fermentation. Sensory evaluation showed that W. koreensis KO3-fermented soymilk has improved bean, roasted nut, and sour flavors as well as an enhanced mouthfeel, appearance, preferability, and overall acceptability compared with those of standard fermented soymilk. With further study and development, soymilk fermented by W. koreensis KO3 could serve as a health-promoting food with favorable sensory qualities.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.382-387
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• 1986

The effect of germination of soybeans on chemical and sensory qualities of soymilk were investigated. The soybeans were soaked and germinated at $25^{\circ}C$ for 5 days prior to grinding. The result showed that a rapid initial decrease in the contents of raffinose and stachyose and a slight increase in protein yield were found after 2 days of germination. Undesirable flavor such as beany and grassy was minimum and total acceptability was maximum for the soymilk prepared from soybeans germinated for two days. Changes in roasted nutty odor and taste were almost identical to the changes of total acceptability during-five day germination.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.139-143
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• 2005

We evaluated grapefruit seed extract for antibacterial activity at varying time intervals and concentration levels against heat tolerant and spore-forming Bacillus stearothermophilus, mesophilic Bacillus subtilis, and food poisoning Staphylococcus aureus. Grapefruit seed extract showed growth inhibitory activity against B. stearothemophilus and B. subtilis, and S. aureus at the level of 0.01 tp 0.03% in nutrient broth. However, when applied to soymilk in a market, grapefruit seed extract at the level above 0.2% effectively inhibited the growth of B. stearothermophilus, However, it failed to completely sterilize the test organisms. On the other hand, B. subtilis and S. aureus were completely sterilized at the level of 0.2% within 48 hrs and 72 h, respectively. The higher concentration of grapefruit seed extracts showed more effective antibacterial activities against the test organisms, but caused deteriorated organoleptic quality and emulsion stability. We could conclude, by applying grapefruit seed extract (0.015%) with thermal treatment (10 min at $121^{\circ}C$) that the microbial stability of commercial soymilk was enhanced greatly.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.216-222
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• 1990

For the improvement of the nutritive value of extruded noodles, dry soymilk residue flour (DSRF) was mixed with wheat How. The effects of the addition of DSRF on the viscosity of wheat flour and the quality of cooked noodles were evaluated As the proportion of DSRF addition was in-creased the viscosity of composite flour was decreased And so were the texture and cooking quality of noodles. To improve noodle-making characteristics of extruded noodles with 10% DRFF, Na-alginate, Na-carboxymethyl cellulose, guar gum crude gluten and xanthan gum were added. Then, the noodle-making characteristics were examined. The viscosity increased with the increase in the concentration of additives and Bnnthan gum was the most effective. The texture of noodles supplemented by Na-alginate 2.0%, Na-carboxymethyl cellulose 2.0%, guar gum 2.0%, xanthan gum 1.0% was similar to that of wheat flour noodles. The results of sensory test (color and texture) was coincidal with the results of instumental tests.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.95-100
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• 1985

Effects of number of washings with solvents on drying rates and physicochemical properties of dried soymilk residues(SMR) were investigated. The dried soymilk residue was prepared by washing the residue with acetone or ethanol, followed by drying at $60^{\circ}C$. Increase of number of washings with a residue/solvent ratio of 1/1.5 resulted in an increase in drying rate and in protein content of the residue while the lipid content decreased. The brightness of the dried residue and the properties of water and oil absorption were also improved by washing with acetone which was advantageous to ethanol for all of the properties measured. Washings more than 3 times with acetone or 2 times with ethanol were found to be less effective in terms of quality improvement. The more addition of dried residue into the mixture of SMR-wheat flour resulted in a linear increase of water and oil absorption characteristics.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.426-432
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• 1988

This study was undertaken to investigate for the possible use of enzymes with ${\alpha}-galactosidase$ and protease activities to remove flatulence factors as well as to improve the yield and protein digestibility in soymilk preparation. The volume and protein yield were not increased significantly by enzyme treatment. The solids yield increased by raising treatment pH 6 to 10, the temperature $30^{\circ}C\;to\;60^{\circ}C$ Enzyme treatment brought about a remarkable increase in TCA-soluble nitrogen compounds and a decrease in the contents of flatulence factors raffinose and stachyose.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.154-162
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• 2006

Cheese analogs using lipoxygenase-defected soymilk and ${\alpha}$-chymotrypsin modified soy protein isolate (SPI) were prepared. Color, textural properties, sensory attributes and melting spreadability of cheese analogs were evaluated and compared with mozzarella cheese, and relationships between textural properties, sensory attributes and melting spreadability of cheese analogs were analyzed. Off-flavors were not mostly discriminated. Cheese analogs containing 10% SPI untreated and containing 6% and 8% SPI treated by ${\alpha}$-chymotrypsin in ${\Delta}E$ value of color were the most similar to mozzarella cheese. Quality characteristics and melting spreadability of cheese analogs were highly affected and improved by ${\alpha}$-chymotrypsin modification. Sensory attributes and melting spreadability of cheese analogs containing 6% SPI treated by ${\alpha}$-chymotrypsin were the most similar to mozzarella cheese, while in textural properties, cheese analogs containing 10% SPI were the most similar with mozzarella cheese. Hardness in sensory attributes was highly positively correlated with hardness (r>0.65), adhesiveness (r>0.56), chewiness (r>0.77) and gumminess (r>0.76) in textural properties, while it was highly negatively correlated with melting spreadability (r>-0.68).

• Proceedings of the KSCN Conference
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• 2005.10a
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• pp.88-88
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• 2005

• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.593-598
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• 2015

This study determined the thermal resistance of Bacillus cereus, Escherichia coli O157:H7, and Listeria monocytogenes in multi-grain soymilk and proposes processing conditions that meet the national standard for retort food products in Korea. D and z values were calculated from thermal inactivation kinetic curves after heating at 55, 60, and $65^{\circ}C$. The D value for B. cereus at $55^{\circ}C$ was the highest (22.8 min), followed by that for E. coli O157:H7 (18.8 min) and L. monocytogenes (17.6 min). At $60-65^{\circ}C$, the order was L. monocytogenes ($D_{60-65^{\circ}C}=3.4-0.9min$), E. coli O157:H7 (3.0-0.3 min), and B. cereus (1.2-0.3 min). The z values for these species were 5.2, 5.5, and $7.7^{\circ}C$, respectively. The Korean national standard for retort food products was achieved by thermal processing at $124{\pm}2^{\circ}C$ for 0.3-2.2 min. This study provides useful data for ensuring both the microbiological safety and product quality of multi-grain soymilk products.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.12-18
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• 1983

Changes in the quality and amino acid composition of soymilk prepared from soaked and germinated soybeans were investigated. Soybeans were soaked in water for 3 hrs and germinated at $18{\pm}1^{\circ}C$ for 5 days followed by water extraction at room temperature, and then the soymilk was boiled for 30 min. The initial yields of total solid and protein after soaking were 80.7% and 88.6%, respectively and decreased slowly during germination. A slow decrease in lipids and a rapid reduction in total sugar content were found during germination. The change in protein fraction content of soymilk showed an initial increase followed by a gradual decrease. The intrinsic viscosity increased rapidly after 3 days of germination to maximum value at 4th day, then decreased. The amino acid composition of protein fraction of soymilk showed little change while that of nonprotein fraction changed significantly. After 4 days of germination, aspartic acid and alanine increased more than twice, and methionine and tyrosine decreased to half of their initial composition in soymilk prepared from soaked soybean.