• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.348-352
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• 1994

Soybean seed consists of two major storage protein, the 7S and 11S globulins. For improving the quality of soybean seed protein, an increase of 11S/7S ratio would be a desirable objective because the 11S globulin contains much more the sulfur-containing amino acids than the 7S globulin. In this study, some soybean varieties were used to investigate the analyzing method for 7S and 11S globulins. 7S and 11S globulins couble be fractionated by their different solubilities in tris buffers. Adjusting the pH and tris concentration were major factors affecting the precipitation of the two globulins. And it was possible to screen the soybean genotypes having aberrant subunit compositions of the two globulins by an sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of total soybean proteins. The ratio of 11S to 7S globulin ranged from 1.29 to 1.38. This paper also dealed with the contribution of protein components in soybean seeds to the physical properties of soycurd. It indicated that the soycurd from crude 11S was remarkably harder than that from crude 7S, and springiness and cohesiveness were slightly higher in soycurd having higher proportion of 11S. So, it may concluded that proportion of protein components in soybean seed can be important factor which controls the suitability for soycurd or other foods.

• Food Science and Preservation
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• v.12 no.5
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• pp.460-464
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• 2005

In order to produce functional soy hydrolysates, we investigated the characteristics of soy hydrolysates prepared with 4 kinds of commercial proteases. The yield was high in protease(B), in which 43.2% soy flour and 61.6% SPI were obtained. The solubility and the contents of total phenolic compound were greatly increased by the treatment of protease(B) along with protease(C). The calcium intolerance was improved after the protease(B) treatment in soy flour or Soybean Protein isolate (SPI). Consideration for the physicochemical characteristics including yield, protease(B) has potential application for the production of soy hydrolysates. After the protease treatment, the beany flavor of soy flour became weak and the bitter taste was strong in both soy flour and SPI. However, there was no difference of beany flavor and bitter taste among delete protease hydrolysates. Nevertheless, further modifications and improvements to the sensory characteristics would be required for the development of a range of products with the hydrolysate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.569-577
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• 1996

This experiment was conducted to investigate the effects of water potential by PEG treatment on germination and quantitative changes of seed storage reserves of soybean [Glycine max (L.) Merr.], peanut(Arachjs hypogaea L.) and corn(Zea may L.). Water potential of PEG(M.W. 10, 000) solution as germination media was 0.0, -0.2, and -0.5MPa. The highest moisture uptake rate was found in soybean seedlings among three crops. Moisture content of seedlings of three crops was decreased at -0.5MPa treatment and seedling length was delayed with water potential decrement. As water potential decreased, decreasing rate of protein content of the seedlings compared to seeds was declined in soybean and peanut. Decreasing rate of starch content of the seedlings was decreased in corn at -0.5MPa treatment. Increasing rate of sugar content of the seedlings was markedly decreased at -0.5MPa treatment in all crops. The results of this experiment showed that availability of moisture and synthesis of sugar for seed germination were influenced below -0.5MPa water potential in three crops.

• Food Science and Preservation
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• v.8 no.3
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• pp.308-312
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• 2001

This study was conducted to investigate the characteristics of yogurt prepared with different mixing ratios of 'Jinpum ' bean and sword bean(Canavalin gladiata). The crude protein content of 'Jinpum' bean used raw material was 38.0%, whereas that of sword bean was 27.5%. The pH and sugar content of ferment solution were deceased significantly up to 4 hours after strain inoculation but reduced slowly artier 8 hours. The content of organic acid and lactic ferments were increased. After 20 hours fermentation there was no significant differences between yogurt processed with 100% 'Jinpum' bean and yogurt processed with 95% 'Jinpum' bean and 5% sword bean. The number of lactic acid bacteria in yogurt processed with 95% 'Jinpum' bean and 5% sword bean was increased up to 20 hours but thereafter was decreased rapidly, showing the similar values compared to that of yogurt processed with 100% 'Jinpum' bean. The color values of yogurt processed with 95% 'Jinpum' bean and 5% sword bean artier 20 hours fermentation were similar to that of yogurt processed with 100% 'Jinpum' bean whereas those of yogurt processed with 90% 'Jinpum' bean and 10% sword bean were no little difference before and after fermentation. In the result of sensory test of yogurt prepared with 95% 'Jinpum' bean and 5% sword bean, adding strawberry syrup was more preferred than apple syrup.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.382-388
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• 1994

For the comparision of the differences in dry matter weight and the chemical composition of soybean seeds in relation to utilization styles and storage durations, the seed coats and cotyledons including embryo axis separated from the seeds of 3 recommended cultivars stored for 3 years and of 5 recommended cultivars and 2 local varieties with black seed coat and green cotyledons were observed in dry weight, germination percentage, protein, oil, soluble sugar, oilgosaccharide, and starch. In the seeds stored for 3 years, dry weight and germination rate were decreased distinctively. This decrease of seed dry matter resulted from the decrease of the cotyledon weight, and the ratio of seed coat to whole seed was increased. For the change of chemical compositions by the decrement of seed dry weight during the storage, protein, oil, and carbohydrate contents of the seed coat were decreased, and protein content of the cotyledon was markedly decreased in the seeds stored for 3 years. The ratio of seed coat to whole seed was higher in small seed than large seed cultivars. In the local varieties, protein and oil contents were 43.59% and 18.25% in the cotyledons, respectively, which were lower than those of recommended cultivars. But starch and sugar contents were 5.70% and 11.58%, respectively, which were higher than those of recommended cultivars. Sucrose, raffinose and stachyose contents were also higher in the cotyledon of the local varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.592-599
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• 1996

The variations of asparagine and aspartic acid contents among the soybean varieties and in the different parts of soybean sprout after the different durations of storage were investigated. Asparagine and aspartic acid are known to have the detoxifying effects on acetaldehyde, which is highly toxic metabolites in the process of alcohol metabolism in the human body. The contents of asparagine and aspartic acid of beansprout showed continuosuly increasing trends along with the days to cultivation with a great varietal difference, especially in the roots. The duration of seed storage did not affect contents of asparagine content; the longer storage decreased aspartic acid content remarkably.

• Food Science and Preservation
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• v.23 no.6
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• pp.811-818
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• 2016

The purpose of this study was to investigate changes in the amino acid content and physicochemical properties of Cheonggukjang prepared by using various soybean cultivars (Daewon, Deapung, Seadanbeak, and Taekwang) and a functional microorganism (Bacillus subtilis HJ18-9). These soybeans were conventional Cheonggukjang (control) and Cheonggukjang fermented with Bacillus subtilis HJ18-9 (treated). The moisture contents of steamed, control, and treated soybean were 62.45~67.12%, 63.28~67.14%, and 64.50~66.87%; amino-type nitrogen contents were 6.53~24.25 mg%, 27.63~122.09 mg%, and 37.29~133.48 mg%; and ammonia-type nitrogen contents were 26.92~47.95 mg%, 45.45~156.36 mg%, and 28.02~121.13 mg%, respectively. The umami taste associated with several amino acids (aspartic acid and glutamic acid) in Cheonggukjang was lower than that for steamed soybeans, while the bitter taste from amino acids (methionine, valine, isoleucine, leucine, and phenylalanine) was higher than that for steamed soybeans. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the molecular weight of steamed soybeans was less than 100 kDa, while control and treated groups showed low molecular weights below 34 kDa, confirming their protein hydrolysis to small molecular weight. These results are information for developing functional fermented soybean paste and diversification using soybean cultivars.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.714-720
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• 1989

Effects of acetylation on conformational changes of glycinin was studied using solvent perturbation, second derivative spectroscopy, near uv circular dichroism spectra and viscosity. Glycinin with purity of more than 93% was used for the experiment. Modification was carried out with acetic anhydride and glycinin with lysine residue modification of 0%, 28%, 65%, 85%, and 95% were used for the experiment. The result of solvent perturbation using some selected perturbants, such as glycerol, ethylene glycol, and dimethyl sulfoxide revealed that acetylation has caused increase In solvent accessibility of tyrosine residues from less than 40% in native protein to more than 70% for 95% acetylated glycinin. This was confirmed by second derivative spectroscopy. Near ultraviolet circular dichroism revealed that the spectra of native and acetylated glycinin were almost identical differing only in intensity and no other useful information could be derived from it. However, in the case of 95% acetylated glycinin the influence of tryptophan on the spectrum was more pronounced Specific viscosity of glycinin also increased by modification, the extent of which depended upon the degree of acetylation. These results supported that acetylation had caused globular conformation of glycinin to be expanded and denatured.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.162-165
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• 1996

Various kinds of jeolpyon (cubed rice cake) differing in roasted soybean flour. content (0, 5, 10, 15, 20%) were prepared to study digestibility, degree of gelatinization and retrogradation rate. Digestibility slightly in creased as soybean content increased. Degree of gelatinization also increased as soybean content increased. Retrogradation rate obtained from the changes in hardness of soybean jeolpyon with the control was 0.528 day and time constant (1/k) was 1.89 days.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.67-74
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• 1983

The studies on the color improvement of the Doenjang (two types of fermented soybean paste : soybean Doenjang and modified Doenjang) using various Aspergillus oryzae strains (6 strains : A, B, C, D, E, F) were conducted with the series of experiments of enzymatic activities (pretense, $\alpha$-and $\beta$-amylase), browning color formation (Lovibond color), major chemical components (amino nitrogen, reducing sugar and others) and sensory evaluation (color, taste and odor). Aspergillus oryzae 2157 (C strain) had a high potential for the color improvement of Doenjang products and was identified as non-browning strain during Doenjang fermentation and storage period. And also this strain was appeared to be in good enzyme activities and flavor characteristics.