• Korean journal of food and cookery science
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• v.11 no.1
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• pp.26-32
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• 1995

This study was carried out to investigate the effect of protease on the functionality of soymilk protein. The protease from Bacillus polymyxa was selected because of the least production of bitter taste and calcium-aggregation. The results are summarized as follows: 1. Solubility of SMP(soymilk protein) and SPI(soyprotein isolate) were lowest at pH 4.7 and increased as the pH value reached closer to either ends. PT-SMP(pretense treated soymilk protein) showed higher solubility at all pH range, especially at pH 4.7 than SMP, SPI. 2. Emulsion activity of three samples was lowest at pH 4.7 and significantly increased as pH approched higher acidic or alkaline regions. PT-SMP showed similar activity to other samples, but less stability. 3. Foam capacity of PT-SMP was lowest at pH 8 and increased in acidic, alkaline pH. PT-SMP showed higher foam capacity at all pH range, but lower foam stability than SMP and SPI. 4. PT-SMP showed higher heat coagulability than other samples at all pH range except pH 4.7.

• 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).

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1128-1134
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• 1997

Lactobacillus helveticus was inoculated to the fermentation liquid containing skin milk powder(SMT) plus soymilk, SMP plus isolated soybean protein(ISP), SMP plus ISP plus whey powder(WP) to increase the nutritional and economic value of commercial soy yogurt. The yogurt fermented with soymilk and SMP showed the lower acid production than of SMP and had significant beany flavor in the product. The yogurt prepared with ISP and SMP showed the higher cell number and lower acid production than that of SMP. Also, the partial substitution of SMP with ISP over 6%(w/w) produced less acceptable product due to gel production. The yogurt prepared by the partial substitution of SMP with ISP, WP and SMP showed the higher cell number and lower acid production than that of SMP and not bring about gel formation unlike the case of ISP. Sensory properties of yogurt substituted SMP with ISP and WP(38:62 mixture) below 4% were not significantly different from that of SMP and the sample containing the mixture over 6% and 0.067% artificial flavor showed lower sensory score due to beany taste than that of SMP. But increase of yogurt flavor up to 0.1% resulted in significantly high score in organoleptic acceptability. The separation of water occured in yogurt prepared by the combined mixture of ISP, WP and SMP, and this problem could be resolved by addition of Na-alginate and PGA at the concentration of 0.1%(w/w).

• 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.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.273-279
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• 1993

Hydrolytic patterns of 11S globulin (glycinin), storage protein of soybean, by soymilk-clotting enzymes Iand IIfrom Bacillus sp. K-295G-7, which was the first soymilk-clotting enzyme to be found in a bacteria, was investigated. The clotting time of about 4~5 min is revealed by the Enzymes Iand II(0.025 units at 35$^{\circ}C$) on the acidic subunit. In electrophoresis, acidic subunit (A$_3$, M.W. 45,000) disappeared almost completely within 2 min and new products corresponding to the molecular weight of 16,000 and 20,000 were formed by the action of Enzymes I and II. Furthermore, Enzyme II produced a degradation compound having a molecular weight of about 30,000. In contrast, the hydrolytic patterns of basic subunit (M.W. 20,000) by Enzymes I and II were similar, but Enzyme II produced low molecular weight products slower than that of Enzyme I.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.369-372
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• 1990

Although the measurement of oil globule size distribution is necessary to detect the process of demulsification, the reasonable methodology for its measurement has not been suggested because the solution of soymilk contains insoluble soybean particle and the protein to interfere with the detection of oil globule or oil content. The oil globule size distribution was measured by the homogeneous suspension and cumulative method under gravitational force or centrifugal force, which were modified with Stokes' low. The geometric mean diameter of oil globules in this soymilk was $033{\mu}m\;and\;031{\mu}m$ under gravitational method and centrifugal method, respectively. The differences of oil globule size distribution in the solutions emulsified by different pressures were detected by this method. The mean diameter of the solutions treated at higher pressure was shifted to smaller size and the distribution pattern of the solutions at higher pressure became more compact around the mean diameter.

• Food Science of Animal Resources
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• v.37 no.4
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• pp.606-616
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• 2017

The objective of this research was to investigate the effects microbial transglutaminase (mTGs) on the physicochemical, microbial and sensory properties of kefir produced by using mix cow and soymilk. Kefir batches were prepared using 0, 0.5, 1 and 1.5 Units m-TGs for per g of milk protein. Adding m-TGs to milk caused an increase in the pH and viscosity and caused a decrease in titratable acidity and syneresis in the kefir samples. Total bacteria, lactobacilli and streptococci counts decreased, while yeast counts increased in all the samples during storage. Alcohols and acids compounds have increased in all the samples except in the control samples, while carbonyl compounds have decreased in all the samples during storage (1-30 d). The differences in the percentage of alcohols, carbonyl compounds and acids in total volatiles on the 1st and the 30th d of storage were observed at 8.47-23.52%, 6.94-25.46% and 59.64-63.69%, respectively. The consumer evaluation of the kefir samples showed that greater levels of acceptability were found for samples which had been added 1.5 U m-TGs for per g of milk protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.878-884
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• 1996

A bacterial strain, designated as Bacillu sp. IJ-3 strain, was shown to produce the extracellular soy protein coagulating enzyme and culture conditions for the production of enzyme by this microbial strain was investigated. The culture medium giving a maximum soy protein coagulating activity was consist of 20%(w/v) soymilk, 2.0%(w/v) glucose, 4.0%(w/v) yeast extract, 5.0%(w/v) polypeptone and 1.0%(w/v) potassium phosphate, monobasic. Initial pH was optimal at 6.0 and the enzyme activity in the culture usually reached a maximal level of fermentation at $35^{\circ}C.$ After the culture medium adjustment where required, enzyme activity was reached maximum at 72 hour of cultivation but this enzyme activity was reduced quickly. It can be assumed that Bacillu sp. IJ-3 strain enzyme has a specificity toward the 75 globulin.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.73-83
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• 2017

This study was conducted to evaluate the chemical composition, digestibility, and energy value of 15 non-conventional feeds produced in South Korea as ruminant feeds. Three Hanwoo steers (body weight, $520{\pm}20.20kg$) fitted with a permanent rumen cannula and duodenal cannula were housed individually in tie-stall barns, followed by a 14-day adaptation period and 3-day experimental period. Chemical composition analysis, in situ nylon bag, and mobile bag technique were used as experiments. As a result of the chemical composition analysis offeeds, crude protein (CP) contentsofmalt meal, perilla meal, soy sauce cake, and soymilk residue were greater than 30%. As a result of the degradability characteristics analysis of feeds using an in situ nylon bag, rumen undegraded protein (RUP) contents of beet pulp, brewer's grain, coffee meal, malt meal, milo bran, perilla meal, ramen residue, and soymilk residue were greater than 50%. Analysis of total digestible nutrient (TDN) values of feeds using an in situ mobile bag showed that TDN values of beet pulp, brewer's grain, makgeolli residue, milo bran, perilla meal, ramen residue, rice bran, soy sauce cake, soybean curd cake, soymilk residue, and wheat bran weregreater than 50%. In summary, these non-conventional feeds have high potential value as good feed resources to replace formulated feeds or roughage. Therefore, the chemical composition, digestibility, and energy value of non-conventional feeds obtained from this study can be used as base data for the manufacture of ruminant total mixed ration (TMR) with improved feed efficiency, reduced feed costs, and reduction of environmental pollution.