• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.13-13
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• 2019

Soybean (Glycine max L. (Merr) is commonly consumed and found in major foods including soymilk, soy sauce, tofu, and soy sprout in Korea and east Asia. In addition, it is common to cook the whole seeds with rice. Soybean is known to have ranges of health benefits including antiaging, anticancer, neuroprotective and antidiabetic taken either as supplement or dietary food. Anthocyanins and flavonoids in G. max are found to be the main contributors to such wide arrays of health benefits. Due to increasing economic values of soybean, development of specialty soybean cultivars is becoming an area of interest worldwide. In this study, 746 black soybean accessions from National Agrobiodiversity Center were characterized as part of an attempt to identify important germplasms of G. max. Seed coats of each accession were analyzed for their total anthocyanin, cyanidin 3-O-Glucoside (C-3-O-G), delphinidin 3-O-glucoside (D-3-O-G), petunidin-3-O-glucoside (Pt-3-O-G), and their whole seeds for crude protein contents. HPLC was used to determine and quantify the anthocyanin compositions while crude protein was determined using Kjeldahl method by Kjeltec auto-analyzer (Kjeltec 8400, Foss, Sweden). Accessions were grouped according to their anthocyanins and protein contents; the mean content of which were correlated to agronomic traits including maturity date, one hundred seed weight, cotyledon color and seed lust color. The results indicated that the total anthocyanin content (TAC) ranged from 273.77 to 6250.52 mg/100 g, with mean value of 1853.03 mg/100 g while the crude protein content (CPC) being between 33.43 and 47.51%, with mean value of 40.81%. The highest number of accessions (45.97%) showed TAC between 1000~1900 mg/100 g while 30.96% of accessions showed CPC between 41~43%. Among the 746 accessions considered, 11 (IT142935, 175818, 175855, 177191, 177209, 177211, 177214, 177216, 177218, 177220, 177274) of them showed TAC above 4000 mg/100 g. C-3-O-G was found to be the major contributor to TAC showing strong correlation. Accessions with green cotyledon color showed high mean TAC compared to those having yellow cotyledon color, and accessions with dull seed lust color showed high mean TAC than those having shiny seed lust color. One hundred seeds weight and maturity date showed positive correlation with all anthocyanin contents, except for Pt-3-O-G in the latter case. The overall result of the present study could be used as background for developing new black soybean cultivars and breeds with high anthocyanin and protein contents. The result depicted that many of the accessions could be used as potential parental lines.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2002.05a
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• pp.82-89
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• 2002

Acid dairy drinks(ADD) are a worldwide product existing in many variations: fruit milk drinks, yogurt drinks, soy milk, butter milk, whey drinks and kefir etc. These drinks are marketed with different shelf lives depending on processing: -Short shelf life(maximum 3 weeks, cold storage) - Long shelf life(2 to 9 months, pasteurized, sterilized or retorted) Acidic protein drinks tend to a separation or destabilization process in the absence of stabilizing system during the shelf life of the ADD. A phase separation results in sedimentation of large particles at the bottom of the package and/or the formation of a serum layer at the top(whey off). These beverages are usually composed of an acid dairy phase (fermented base)or a natural base(milk, soymilk etc.)with an acidic medium (fruit phase: pulp, fruit concentrate etc.) which can be flavored. Sugar and stabilizers are added. It has been proved since the late 1950's that adding high methoxy pectin (HM pectin)to acid milk drinks is the best way to prevent the formation of a sediment and/or the whey off. In this presentation, we explain about stabilization mechanism of ADD induced by pectin. Applications and market trend of ADD in Asia and Europe are explained.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.181-184
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• 1995

Ultrafiltration was applied for the production of soy-oligosaccharides from bean cooking water(BCW), a by-product recovered in soymilk processing. The ultrafiltration of BCW on a membrane of 20,000 cutoff molecular weight recovered most oligosaccharides as permeate with concomitant removal of protein at 40% when volume concentration ratio(VCR) exceeded 5.0. When the VCR exceeded 5.0, membrane rejection value(MRV) for protein started to increase slowly while the MRV for sugar showed a sharp increasing trend showing 6.57% at VCR 5.0 and 19.96% at VCR 10. The optimum VCR based upon the MRV's was 5.0. Maximum recovery of soy-oligosaccharides was, however, obtained at VCR 10.0.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.95-106
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• 2002

Soybean is one of the most important sources of protein and oil in the world. Recently, emphasis has been laid on the chemical composition of soybean seeds for the processing soybean foods. Improvement of soybean components has been expected to improve food-processing quality for the processed soybean products such as soymilk and various edible ingredients as well as fur the traditional soyfoods. In Korea, soybean breeding research programmes have been focused on the quality of the products derived from soybean with yield stability, and some new modified soybean varieties haying good food-processing quality were developed recently. So the efforts of establishing standard and standardization of products in soybean are important. Three main categories should be considered in view of soybean seed quality; the marketing value such as grain size, shape, and appearance; the eating and processing value such as dehulled ratio, water absorption rate, and benny flavor; the nutritional value such as protein, lipid, and carbohydrate contents. And the new frontiers in research are looking at the functional nutrients in soybeans and how to improve them. In case marketing value, mainly the appearance is evaluated, therefore, each country has an application of standard related to quality. Each determination of standard class, heat-damaged kernels, splits, and soybeans of other colors is made on the basis of the grain when free from foreign materials. But processing value and nutritional value for standardization were not studied in detail till now. In addition, soybean has potential roles in the prevention and treatment of chronic diseases, most notably cancer, osteoporosis, and heart disease. The functional nutrients include a protease inhibitor, phytic acid, saponins, and isoflavones, etc.. It is believed that standardization of soybean quality should perform to overcome the difficulties, relatively high price of domestic soybean products has weakened the competitive power, in the market related to WTO. So, we should focus on further research into the evaluation and establishment of quality-standard in soybean.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.370-374
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• 1995

By exposing the complex enzyme solution to alkaline condition, it was possible to remove the protease activity selectively without inactivation of soybean cell wall degrading activity of the crude enzyme complex produced by Aspergillus niger CF-34. Optimum reaction conditions were as follow. pH was $9.0{\pm}0.1$, temperature was $20^{\circ}C$ and reaction time was 30 min with gentle stirring. Over 90% of protease activity could be eliminated while the activities of pectinase, polygalacturonase, xylanase, carboxymethyl cellulase and soybean cell wall degrading enzyme were maintained to $80{\sim}100%$. Through alkali treatment, it was discovered that the quality and organoleptic properties of soy protein produced by this enzymes were improved because the hydrolysis of protein and formation of bitter peptide were decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.75-81
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• 2003

Rheological properties of micronized full-fat soyflour (MFS ) milk were determined according to solid content, heat-treatment and type of coagulants. Heat-treated MFS milk showed a pseudoplastic flow pattern. The consistency and flow index of heated MFS milk was greatly affected by increasing the concentration of MFS and/or soy protein isolate (SPI). Apparent viscosity of MFS milk was gradually decreased by heating below 6$0^{\circ}C$, but was drastically increased by raising temperature further. Addition of coagulants and SPI resulted in dropping the temperature that allows to increase apparent viscosity drastically. A coagulant for MFS tofu was formulated based on the gelling Property of a single coagulant. The textural properties of MFS tofu were improved using 7.1% total protein fortified with SPI.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.22-27
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• 2006

This study was carried out to determine the optimum conditions for making soybean curd(or tofu) from defatted soybean flour.. Heating soymilk above $80^{\circ}C$ for at least $5{\sim}10\;min$ was necessary for soybean protein to form aggregates during subsequent coagulation process with glucono-${\delta}$-lactone(GDL). For maximum yield of tofu, with water content of approximately 80%, extra addition of 20 g of oil and 5 g of GDL per 425 g of soybean flour was needed. Maintaining soymilk temperature around $75^{\circ}C$ for 5 min was necessary when GDL was used as the coagulant.

• Food Science and Preservation
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• v.20 no.5
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• pp.705-711
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• 2013

Gamma amino butyric acid (GABA), known as a non-protein amino acid and major inhibitory neurotransmitter in the brain, has several functional properties such as neurotransmission, induction of hypotension, tranquilizer, and diuretic effects. The purpose of this study was to isolate and identify lactic acid bacteria, producing high GABA in fermented soy curd. Thirty-two strains of tofu-forming lactic acid bacteria were isolated from kimchi which a traditional Korean food fermented with many kind of microorganism. Among 32 strains, four strains (strain No. 10, 104, 214, 249) formed firm soycurd. In order to select lactic acid bacteria having high GABA producing potential, the isolated strains were cultured in the soymilk and fermented for 48 hr at $37^{\circ}C$. A strain No. 383, which showed highest GABA contents in fermented soycurd, was identified as L. sakei by 16S rDNA sequencing and API analysis, and named as L. sakei 383. L. sakei 383 showed optimal growth up to 24 hr at $35^{\circ}C$ in MRS broth. The optimal time and temperature for GABA production were 18 hr and $35^{\circ}C$ in soymilk. In the optimal condition time and temperature, GABA content of fermented soycurd by L. sakei 383 was 8.65 mg/100 g.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.78-85
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• 1997

To determine the optimum coagulants concentrations for preparing soybean-curds, the transmittance of soybean-curd whey using spectrophotometer has been measured. The textural properties of soybean-curds were examined by texture analyzer and sensory evaluations. The general components, oligosaccharides and amino acids in soybean-curd wheys were analyzed. Protein patterns of soybean-curd wheys comparing with soyflour and soymilk were investigated. By texture analyzer, hardness, cohesiveness, springiness, and gumminess of Cacl$_2$ soybean-curd, MgCl$_2$ soybean-curd were higher than those of CaSO$_4$ soybean-curd and GDL soybean-curd. In the sensory evaluations, CaSO$_4$ soybean-curds and GDL soybean-curds were smoother and moister than others. Glutamic acid and aspartic acid were the first two abundant amino acids in three kinds of soybean-curd wheys, but arginine was the most abundant amino acid in GDL soybean-curd whey. Total sugar content of soybean-curd wheys were about 12-13 g/l, and the main sugars among 5 kinds of sugars were sucrose and raffinose. Electrophoresis using SDS-PAGE showed that glycinin and P-conglycinin, the main proteins of soybean appeared in soy flour and soymilk, and only low molecular weight subunits appeared in soybean-curd wheys.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.261-266
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• 1984

Soymilk residue was washed separately with acetone, ethanol, isopropyl alcohol and n-hexane, and then dried at $45^{\circ}C$. The dried residues were evaluated for drying rate, color and chemical and functional properties. Washing with acetone resulted in the shortest drying time (1hr) and the highest in protein content (48.8%) and in Hunter 'L' value. The dried residues after treatment with acetone and alcohols showed relatively high values of 4.3-4.7g/g and 8.5-8.7g/g in oil and water absorption, respectively. Addition of the acetone treated residue to wheat flour at a level of 10% affected little in Amylograph viscosity while those treated with other solvents caused a significant decrease in the viscosity.