• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.89-98
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• 2014

In this study, soybean is used to produce soymilk according to various extracting methods and heating time. Specifically, the soy slurry is being filtered before being heated, or heated before being filtered. Following that the soymilk produced is freeze-dried to be powdered, and then, the quality characteristics of the powdered soymilk are mutually compared to determine the applicability of various food additives. The freeze-dried soymilk powder shows 2.03~6.35% of moisture content, and in terms of unit quantity, retained more proteins, which suggests that the ratio of protein extraction is higher than any other nutrients. Accordingly, the protein coefficient is significantly higher in soymilk powder being heated and processed than in raw soybeans. In particular, protein coefficient is the highest in the soymilk which is heated for 20 minutes before being filtered (SHBF20). The longer the heating time was, the trypsin inhibitor (TI) tended to be far less active. Such an inactivation seems to be more apparent in the "SHAF" soymilk powder than "SHBF" soymilk powder. Because protein had to be denaturated by heating for soymilk, the nitrogen solubility index (NSI) of soymilk powder is decreased considerably, while the protein digestibility, water absorption, emulsification and foaming activity all increase. Oil absorption tends to decrease slightly. As discussed above, the soymilk heated for 10 minutes after being filtered (SHAF10) and the soymilk heated for 20 minutes before being filtered (SHBF20) show optimum processing conditions for soymilk powder.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.381-391
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• 2006

The rheological properties of dough made the substitution of wheat flour(composite flour) at the levels of 0%, 5%, 10% and 15% soymilk residue flour, with addition of vital wheat gluten at the levels of 3, 6 and 9% were investigated. And nutrition contents of soymilk residue flour were analyzed. The results were as follows; Principal components of soymilk residue flour were 22.0% crude protein, 13.2% crude lipid, 54.3% carbohydrate, 27.2% dietary fiber and $220{\mu}g/g$ isoflavones. Free amino acid component of soymilk residue were L-glutamic acid, L-leucine, L-lysine, L-valine, L-phenylalanine, L-isoleucine, L-threonine, L-methionine and L-cystine. Total dietary fiber content of bread with soymilk residue and wheat flour were 5% soymilk residue; 3.50%, 10% soymilk residues; 4.65%, 15% soymilk residues; 5.96%, and wheat flour bread: 2.1% respectively Mixing water absorption capacity was increased by increasing amounts of added soymilk residue and vital wheat gluten. Dough development time was increased by increasing amounts of added soymilk residues, while decreased by increasing amounts of vital wheat gluten. The dough volume of composite flour with 5%, 10% and 15% soymilk residue flour were the smaller than wheat flour dough. But the dough volume was increased by added vital wheat gluten, and the composite flour with 5% soymilk residue flour and 9% vital wheat gluten was better than the others. This study proved that the dough volume of composite flour with 5% soymilk residue flour and 9% vital wheat gluten was better than the others. On the other hand, the soymilk residue flour contains dietary fiber, isoflavone, protein, lipid and carbohydrate. Therefore the soymilk residue flour will be very useful as food material.

• Journal of Community Nutrition
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• v.5 no.3
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• pp.132-140
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• 2003

The objective of this study was to investigate the effect of soymilk and exercise on bone mineral density (BMD) in underweight college women of 19-22 years of age, who had lower bone mass. The BMD of the lumbar spine and femoral neck was measured for 52 underweight college women. Among them, 33 subjects, whose t-score value was below -1, were selected. Questionnaire survey, anthropometrical measurements, dietary recall, analysis of BMD, fasting serum osteocalcin and urinary deoxypyridinoline (DPD) were conducted before and after the 10 week study. The 33 subjects were divided into 2 groups： soymilk group (n=19), and soymilk ＋ exercise group (n=14). The soymilk group was given 400$m\ell$ soymilk containing 60mg of isoflavones on a daily basis and the soymilk ＋ exercise group exercised three times a week with a daily intake of 400$m\ell$ soymilk for 10 weeks. The average ages of the soymilk group and the soymilk ＋ exercise group were 21.1 years and 20.4 years, respectively and, there were no significant differences between the soymilk group and the soymilk ＋ exercise group in the areas of height, weight or Body Mass Index (BMI). At the baseline, the mean daily energy intake of the soymilk group and the soymilk ＋ exercise group was 1,597.9kcal (79.43％ of RDA) and 1,704.2kcal (85.2％ of RDA), respectively. The mean calcium intake of the soymilk group (408.3mg) was not significantly different from that of the soymilk ＋ exercise group (389.4mg). Despite the 400$m\ell$ soymilk supplementation, there were no significant changes of nutrient intake in either group after treatment. However, there were significant increases in BMD's of lumbar spine and femoral neck in both groups. There were some increases in the serum osteocalcin level and decreases in the urinary deoxypyridinoline level as well. BMD change of the soymilk group was not significantly different from that of the soymilk ＋ exercise group. In conclusion, supplementary intake of soymilk (containing 60mg of isoflavones) resulted in a significant increase in the BMD's of the lumbar spine and femoral neck in underweight college women with low bone mass. However, exercise did not result in any significant changes in the BMD's, implying the necessity for more intensive and specific long-term physical training for any substantial changes. Further investigation is necessary to determine the exercise that most strongly affects BMD.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.14-20
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• 1992

Some microorganisms isolated from soil, including some bacteria and fungi, were found to secrete an extracellular soymilk-clotting enzyme. Among them, an isolated fungus showed the highest soymilk-clotting activity and the strain was assigned to genus Penicillium based on its cultural and morphological characteristics, and designated as Penicillium sp. L-151K. Soymilk-clotting enzymes A and B produced by Penicillium sp. L-151K were purified by ammonium sulfate precipitation and chromatographies on Sephadex G-25, CM-Sephadex, Sephadex G-100 and phenyl-Toyopearl gel. The two purified enzymes A and B were found to be homogeneous by polyacrylamide gel electrophoresis at pH 9.5. The molecular weights of enzyme A and B were 24, 000 and 40, 000, respectively, by gel filtration on Sephadex G-100. Enzymes A and B coagulated soymilk optimally at $60^\circ{C}$ and were stable up to $50^\circ{C}$. Both enzymes were most active at pH 5.8 for soymilk coagulation, and were stable with approximately 80% of original activity from pH 3.0 to 5.0. Each enzyme was an acidic protease with an optimum pH of 3.0 for casein digestion. The soymilk-clotting efficiency of these enzymes was improved with $CaCl_2\;or\;MgCl_2$ when making soymilk-curd.

• Journal of the Korean Society of Food Culture
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• v.31 no.6
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• pp.605-615
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• 2016

The objective of this study was to prepare acorn bread added with soymilk in order to improve its quality and develop the best possible recipe. The loaf volume, color, texture and sensory evaluation of acorn bread added with soymilk 10~40% were measured during the storage period. The L-value significantly decreased upon addition of 40% soymilk. A-value increased, but b-value decreased. During the storage period, the L- and a- values increased except 2 days at room temperature and 7 days in a freezer, whereas b-value decreased. For textural measurement, hardness, springiness, gumminess and brittleness increased significantly upon addition of soymilk. However cohesiveness decreased for 2 days of storage, whereas gumminess and brittleness for 1 day of storage at room temperature. Freezer storage for 1 day reduced cohesiveness, and gumminess for 4 and 7 days, respectively, and brittleness after all storage periods. The sensory evaluation showed that acorn bread added with soymilk 20% produced the best results in color and taste. The bitter aftertaste increased according to addition of soymilk with lower scores. Softness, chewiness and overall preference decreased significantly. Therefore, 10% soymilk addition got the best scores in aftertaste, softness, chewiness and overall acceptances.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.8-13
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• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• Journal of Nutrition and Health
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• v.28 no.10
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• pp.986-994
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• 1995

This study was to examine the effect of phytate on the protein digestibility and calcium, iron and zinc availability in phytase treated soymilks digested with pepsin and pepsin-pancreatin in vitro. Also, the bending between phytate and protein in soymilks was investigated by means of SDS-PAGE. The content of phytate in soymilk was reduced by phytase treatment. As the content of phytate decreased, the protein digestibility increased in soymilk treated with the digest enzymes in vitro. The reduction of phytate content in soymilk improved the availability of all calcium, iron and zinc. Although the availability of calcium increased, the amount of change was small. The phytate reduction increased most the availability of iron. A number of bands of high molecular weight protein in soymilk disappleared in SDS-PAGE by lowering the phytate content with phytase treatement on soymilk.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.795-800
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• 2016

The objective of this study was to propose motivation for the analysis of consumer's purchasing behavior and willingness to pay for the new soymilk products in cooperative stores. We surveyed the purchasing behavior, willingness to purchase, willingness to pay, and impact factors on willingness to pay. The results indicated that most consumers drank soymilk more than once per week. The reasons for consuming soymilk were health, nutrition, and taste, in order. When purchasing soymilk, consumers considered environment-friendly, quality, country of origin, brand, and price, consecutively. Taste was also an essential quality factor. Thus, consumers showed some willingness to purchase new soymilk products. In addition, cooperative members considered environmental characteristics of raw material and improvement of preference for final product as more important than functionality or food additives. Differentiation of process and marketing strategies are required for the development of soymilk products for cooperative members.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.443-448
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• 2005

Isoflavone content of soymilk prepared with germinated soybean significantly increased. Soymilk prepared with Shinpaldal-2 germinated far 12 hr showed maximum 5.552 mg/g isoflavone. Solid content in soymilk increased from 5.68 to 6.02% for Shinpaldal-2 and from 5.30 to 6.10% for Seomoktae with 24 hr germination. 'L' values of soymilk increased, whereas 'a' and 'b' values decreased. Viscosity of soymilk decreased, while stability increased as germination time increased up to 24 hr, Organoleptic flavor properties of soymilk improved, showing decrease in benny and increase in savory flavors. Acceptance test showed soymilk prepared with 12 hr germinated Shinpaldal-2 showed highest acceptance, while Seomoktae soymilk showed least.

• Food Science and Preservation
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• v.15 no.6
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• pp.903-908
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• 2008

This study investigated protein changes in soymilk and whole soymilk due to enzymatic hydrolysis. The total free amino acid contents of low molecular weight soymilk (LSM) and low molecular weight whole soymilk (LWSM) were higher than soymilk (SM) and whole soymilk (WSM). The essential amino acid content was similar in SM and LSM, but was higher in LWSM than WSM. In SDS-PAGE performed to tendency of becoming low molecules, the soy protein molecular weights were 3372 kDa for SM and WSM, but 17 kDa or less for LSM and LWSM. Also, high molecular weight protein spots were evident in 2-D electrophoresis of SM and LSM, but only low molecular weight protein spots of various sizes were evident in WSM and LWSM. This suggests that the high molecular weight protein in SM and WSM is changed to low molecular weight protein by enzymatic hydrolysis. Further investigations of the separation and qualities of these proteins are required.