• Journal of the Korean Professional Engineers Association
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• v.17 no.4
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• pp.28-39
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• 1984

Experiments were carried out for the development of a processing method of soybean into full-fat or defatted flour, using two varieties of soybean (kwangkyo produced in Korea and Bragg produced in India) Samples were subjected to dry dehulling, size reduction and wet heat treatment processes to make soybean flours. The quality of soybean flours were evaluated, and the results obtained were summarized as follows. 1. Crude fiber content of dehulled soybean was under 3.0% which indicated satisfactory dehulling, and there was no significant difference in crude fibre content between two varieties. 2. When dehulled soybean was cracked into soy grits by a hammer mill, 98.71∼98.86％ of the soy grit was in the range of 10∼18 mesh which was the optimum size of particle for quick and uniform penetration of heat into the intra-particle air spaces. 3. Moisture content of soy flour after steam treatment at 15 psig for 5 to 30 min was only 0.29∼1.68% which did not hinder the next milling operation. 4. From the color analysis of soy flours, it was observed that the dominant wavelength for all the samples are in a very narrow range from 575 to 581 nm and the color variation was from yellow to yellowish orange. Twenty to twenty five ％ higher reflectance was observed in the defatted flours than full fat flours. The ％ chroma of the defatted flour slightly increased as the duration of steaming of soy grits increased, whereas that of the full-fat flour did not. 5. The protein extractability in the defatted flour at pH 7.6 showed progressive decrease in solubility from 48.40％ (Bragg), 75.20％ (kwangkyo) for untreated flours to 9.75％ (Bragg), 26.27％ (kwangkyo) for 30 min steaming. But Kwangkyo variety showed twice higher protein extractability than Bragg variety.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.732-738
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• 1991

Corsoy 79 soybeans were ground into 8-(coarse) and 24-mesh (fine) full-fat soy flours. From the particle size analysis, the 8-mesh full-fat soy flours were found to have larger values for geometric mean diameter and geometric standard deviation. However, the distribution moduli of coarse and fine soy flours were similar and indicated soybeans were nearly 'brittle'. Development of hydrolytic and oxidative rancidities of coarsely and finely ground full-fat soy flours were followed from grinding to 24 hrs later. No increases in peroxide value and conjugated dienes in the oil and hexanal content in the headspace of the flour were observed when the moisture was 10.7% or less. At 14.9% moisture and above, lipid oxidation increased with increased moisture content and storage time. Free fatty acid contents increased slightly at all moisture contents. However, hydrolysis did not exceed 0.06% over the moisture range of 4 to 18%, which is of little practical significance. Fine grinding increased oxidative and hydrolytic rancidities, especially at 14.9% moisture and above. these findings indicate that raw soybeans can be ground to full-fat soy flours and stored up to 24 hrs without undergoing significant lipid and flavor deterioration if the moisture content is 11% or less.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1043-1048
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• 2004

This study was carried out to investigate the effect of soy protein dispersibility on the bread making properties when Doenjang powders (DP) were added to the bread formula at the levels of 2.5 or 5.0%, comparing with full fat (FSF) or defatted (DSF) soy flours which contain same protein contents as those of DP. Protein dispersibility indices (PDI) for DP, FSF, DSF and strong wheat flour were 57.1, 7.3, 10.8 and 32.8%, respectively. Addition of DP decreased significantly the resistance to extensibility of wet gluten and increased its extensibility. However, FSF and DSF showed different changes in gluten rheology due to their PDI. In correlation coefficient values, PDI affected positively both gluten extensibility (r=0.98, p<0.01) and ovenspring (r=0.88, p<0.05) resulting in loaf volume and texture improvement of bread with addition of DP.

• Korean Journal of Food Science and Technology
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• v.2 no.2
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• pp.1-7
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• 1970

1) A process was described for the preparation of drum-dried weaning food containing about 20% protein and based on a blend of sweet potato, full-fat soy flour, minerals, vitamins and methionine. 2) The protein efficiency ratio of this product was 2.63 as compared to 3.30 for the blend containing corn starch in place of sweet potato. This is attributed to the partial destruction of available lysine in the presence of sweet potato during the drum-drying process. 3) Overall nutritive value of the weaning food was comparable to milk food and control food based on corn starch and soy flour in terms of feed efficiency, body composition and protein retention.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.51-53
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• 1985

Soy milks prepared from full-fat soy flour, defatted soy flow, soy protein concentrate (SPC) and soy protein isolate (SPI) were fermented with Lactobacillus acidophilus. Effects of lactic fermentation on the flavor and volatile compounds of soy milks were investigated. Sensory evaluation showed that the flavor of soy yogurt beverages was inferior to that of milk yogurt beverage and the flavor of SPI-yogurt beverage was better than that of other soy yogurt beverages. SPI-milk fermented with L. acidophilus was more acceptable than unfermented SPI-milk. Lactic fermentation reduced n-hexanal in SPC-milk and SPI-milk while it increased diacetyl in both soy milks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.904-909
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• 2005

To produce functional food ingredient from the soybean curd residue (SCR), alkaline fermentation was performed with SCR from cold processed (D-SCR) or hot processed (P-SCR) tofu. The solid- state fermentation was performed by Bacillus firmus NA-1 at $42^{\circ}C$. The fermentation of heat-treated D- SCR resulted in higher production of peptides and fibrinolytic enzyme compared with D-SCR without heating. The P-SCR showed higher production of peptides, fibrinolytic enzyme, indicating alkaline pH after fermentation for 18 hr. When the moisture content of P-SCR was reduced to $60\%$, the production of peptides and fibrinolytic enzyme were enhanced. The P-SCR fortified with $10\%$ MFS (micronized full-fat soy flour) showed higher fibrinolytic enzyme activity and consistency index by fermentation of Bacillus firmus NA-1 Furthermore, the P- SCR fortified with $20\%$ MFS indicated relatively higher peptide content, fibrinolytic enzyme activity and enhanced flavor. By increasing the addition of MFS, the peptide content of fermented P-SCR was increased significantly, but fibrinolytic enzyme was slightly decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.115-120
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• 2006

To convert the soybean curd residue (SCR) to functional food ingredient, alkaline fermentation of SCR was performed by Bacillus firmus NA-1 and Bacillus subtilis GT-D for 22 hr at $42^{\circ}C$. The micronized full-fat soy flour (MFS) was fortified to reduce the moisture content as well as to supply protein source. The mucilage and flavor productions in the fermented SCR were enhanced by the fortification of $20\%$ MFS. The peptide production from the SCR fermented with B. subtilis GT-D substantially increased when judged by the detectable amount of tyrosine $(480\;mg\%)$. The production of fibrinolytic enzyme was increased by the fermentation for 22 hr, indicating the relative activity of $62\%$ (B. firmus NA-1) and $47\%$ (B. subtilis GT-D), respectively. The SCR fermented by B. firmus NA-1 and B. subtilis GT-D indicated the consistency of $1.95\;Pa{\cdot}s^n\;and\;0.21\;Pa{\cdot}s^n$, respectively. After freeze-drying, the protease activity (615 unit/g) and a-amylase activity (180 unit/g) were obtained from SCR fermented by Bacillus firmus NA-1 and Bacillus subtilis GT-D, respectively.