• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.739-747
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• 1997

This study was performed to clarify various conditions on the test of lipoxygenase-l and to establish the application of new test method for varietal improvement of soybeans in order to decrease beany flavors. Potassium borate and Tris were used as buffer and O.1M potassium borate solution showed the best result for the lipoxygenase-l test. In the range of pH 8.5~9.0 of the buffer, 2mM linoleic acid as substrate was effective. For color development, 100$\mu$l of two solutions(KI and starch) were added to the half soybean seed, successively. The substrate solution included linoleic acid was stored safely for 10 days at 4$^{\circ}C$ in refrigerator and for 4 days at room temperature. The best result was as follows; the 1ml of substrate solution[0.1M potassium borate(pH 9.0), 0.1％ Tween-20, 2mM linoleic acid] was added to the chipped half soybean seed in l.5ml plastic tube, waited for 15 minutes, and 100$\mu$l of color development solutions(5％ saturated KI in 15％ acetic acid, 1％ starch) were added to the tube, successively. After 4 hours, the purple color was observed in the upper phase of the plastic tube in the presence of lipoxygenase-1 and milky color in absence of lipoxygenase-1. The purple color was stable from 4 to 24 hours. There was no interfering effect by lipoxygenase-2 and -3. The plastic tube should be placed in the tube stand without shaking during the lipoxygenase-l test.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.427-431
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• 2002

Lateral roots of soybean sprout might reduce the quality. The study was done to measure the effect of light quality treated during 24 hour imbibition or 6 day culture on growth and development of soybean sprouts on the 6th day after culture. With the soybean seeds imbibed in 4 ppm benzyladenopurine (BA) solution for last 6 hours of the imbibition, blue and red lights were treated during the imbibition, but during 6 day culture, blue and red or far-red light treatments were done for 50 minutes or 5 hours a day, respectively, the periods taking for their cotyledons to turn green color, On the 6th day after culture, the soybean sprouts were classified by 4 categories on the base of hypocotyl length;＞7cm, 4 to 7cm, ＜4cm and non-germination, and their lateral roots, hypocotyl diameters and fraction dry weights were measured. Blue and red lights treated during the imbibition completely blocked lateral root formation regardless of the lights treated during the culture, and showed nearly the same rate of hypocotyls of longer than 4cm. The period of each light treatment forced during the culture did not influence the growth of soybean sprouts. far-red light treated for 5 hours everyday, however, had the least rate of seed germination and hypocotyls of longer than 7cm of the light quality treatments. In addition, red and far-red lights almost equally having the commercial soybean sprouts of longer than 4cm hypocotyls move elongated and selenderized than blue light and dark treatment, meaning the growth and morphology of soybean sprouts was affected by light treatments during the culture.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.329-332
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• 2003

The effect of garlic addition on quality and shelf-life of soybean curd was investigated. The yield of garlic soybean curd slightly decreased in proportion to amount of garlic added. In the case of texture, hardness of the garlic soybean curd increased when $5{\sim}10%$ garlic was added, whereas hardness, adhesiveness, cohesiveness, springiness and chewiness significantly decreased in the case of 20% garlic added. Microbial counts of soybean curd stored in sterilized distilled water as tofu-immersion solution increased, whereas pH decreased during storage at $15^{\sim}C$. During all storage periods, microbial counts of the soybean curds containing garlic were always lower than that of the ordinary soybean curd. These results imply that garlic is a useful additive in suppressing the proliferation of aerobic microorganism and has a potential use in extending the shelf-life of soybean curd. According to yield, textural properties and shelf-life data, the suitable concentration of garlic was around $5{\sim}10%$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.921-925
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• 2003

To control blood glucose level as close to normal is the major goal of treatment of diabetes mellitus. $\alpha$-glucosidase is the enzyme to digest dietary carbohydrate and inhibition of $\alpha$-glucosidase could suppress postprandial hyperglycemia. The methanol extract of soybean sprout was tested for the inhibitory activities against $\alpha$-glucosidase in vitro. Soybean sprout extract inhibited yeast $\alpha$-glucosidase activity by 24.5% at the concentration of 5 mg/mL. The methanol extract of soybean sprout was subsequently subjected to sequential fractionation with hexane, ethyl acetate, butanol and water. Among the fractions tested ethyl acetate-soluble fraction showed relatively strong inhibition against $\alpha$-glucosidase by 36.3% at the concentration of 5 mg/mL. Acarbose, standard $\alpha$-glucosidase inhibitor, inhibited $\alpha$-glucosidase activity by 40.1%. The ability of soybean sprout extract to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. Starch solution (1 g/kg) with and without the methanol extract of soybean sprout (500 mg/kg) was administered to diabetic rats after an overnight-fast by gastric intubation. A single oral dose of soybean sprout extract inhibited the increase in blood glucose levels significantly at 60, 90, 120, 180 min (p<0.05) and decreased incremental response areas under the glycemic response curve significantly (p<0.05). These results suggest that soybean sprout might exert hypoglycemic effect by inhibiting $\alpha$-glucosidase activity.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.396-400
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• 1995

The antioxidant effects in soybean oil was investigated by browning reaction mixtures formed by sugar and reaction temperatures above 110$^{\circ}C$. 0.1 M solution of xylose, glucose and sucrose were heated at 110, 120, 130, 140 and 150$^{\circ}C$ for 24 hrs respectively. A reaction rate constant(k), activation energy (Ea) and Q$\sub$10/ value were determined by color intensity that was measured absorbance at 490 nm in each temperature. Soybean oil containing the ethanol extracts taken from the browning reaction mixtures that were heated at 110, 130 and 150$^{\circ}C$ was stored in an incubator kept at 45.0${\pm}$1.0$^{\circ}C$ for 24 days. The results are as follows: 1. When 0.1 M solution of xylose, glucose and sucrose were heated at 110$^{\circ}C$ and 120$^{\circ}C$, the intensity of glucose browning mixtures was the highest, but heated at 150$^{\circ}C$, the color intensity increased in order of xylose > glucose > sucrose after 24 hrs. 2. The reaction rate constant (k) was increased rapidly above 140$^{\circ}C$ and appeared maximum at 150$^{\circ}C$, esp. xylose was the highest. The activation onergy (Ea) of xylose was the highest as 93.28 Joule/mole and the Q$\sub$10/ value of xylose was appeared 1.28. Q$\sub$10/ value was also the highest in xylose. 3. The browning reaction mixtures that were heated at 110$^{\circ}C$ appeared little antioxidant effects. But, in heated at 130$^{\circ}C$ and 150$^{\circ}C$, the antioxidant effects appeared in sucrose browning reaction mixtures. Therefore, in browning reaction mixtures that heated above 110$^{\circ}C$, only sucrose browning reaction mixtures appeared antioxidant effects and xylose, glucose appeared little antioxidant effects. On the contrary xylose and glucose increased peroxide values of soybean oil.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.833-836
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• 2004

Effects of pickling soybeans in acidic solution on soybean isoflavone, and pH and color of immersing solution were investigated. Soybean cultivars, Seoritae and Seomoktae (black beans) and Myeongju-namul (yellow bean), were soaked in persimmon vinegar for 10 days at $20^{\circ}C$. Isoflavone content increased rapidly during pickling, reaching 51.8 (Seomoktae)-106.8% (Myeongju-namul). Increase of aglycone types, from 6.2-9.3% to 20.9-50.8%, was particularly noted, while glycosidic ones were less affected. Acidity of persimmon vinegar increased from 3.4 to 4.4 up to 4 days of soaking and decreased slowly thereafter. Color 'L' and 'b' values of persimmon vinegar decreased significantly, whereas 'a' value increased in black beans. All color values of yellow beans were less affected.

• Food Engineering Progress
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• v.15 no.4
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• pp.305-310
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• 2011

Edible films were developed from defatted soybean meal (DSM), a byproduct from the soy product industry, investigating the effects of the concentrations of DSM and glycerol and the treatment of high pressure homogenization (HPH) on color, water vapor permeability, and tensile properties of the films. The physical properties of the developed films (DSM films) were compared to those of the films made of soy proteins isolated from the DSM. DSM films were obtained by drying film-forming solutions prepared with DSM powder, glycerol, and water and with and without HPH at 152 MPa. HPH resulted in the formation of continuous and uniform films. Water vapor permeability of the films increased with increase in the concentration of glycerol and decreased by high pressure homogenization. The increase in the glycerol concentration in the film-forming solution prepared without HPH decreased the tensile strength and elastic modulus of the films. However, this effect was not observed with the HPH-treated solution. DSM films possessed higher tensile strength and percentage elongation than the film of soy protein, implying the potential for the DSM film to be applied to food product as an edible film.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.23-30
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• 2022

This study investigated the characteristics for rice husk pulverization and surface modification of biomass byproducts composed of rice husk, corn extract gourd, wheat bran, and soybean curd. The size of particles of rice husk was at 6.44 ㎛ and represented the most affordable material for preparing the bio-degradable film among the tested byproducts. The silane treatment and adding 2% of ESO (Epoxidized soybean oil) and 3-aminopropyl triethoxysilane solution mixed in a 1:1 ratio were best to the surface modification and SEM-based particle shape. Above the results, adding 2% of mixed solution after silane treatment of rice husks processed through an air classifying mill (ACM) allows for its use as a raw material of bio-degradable plastic film.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.153-157
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• 1999

Three varieties of soybean (Joonjul, Iksan and Eunha) were cultivated by a standard procedure and by the treatment of chitosan solution (1% chitosan in 0.25% acetic acid) for 5 days. In the chitosan treated soybean sprouts (CTSS), the growth rate and weight increase were higher than in the control group. The growth rate of CTSS (Iksan) was 25.4% higher and the increase of fresh weight of CTSS was 8.5% higher than those of control group. Dry weight of whole soybean sprout in the control group decreased during cultivation, but that of CTSS slightly increased after 2 days cultivation. In the control group, dry weight of hypocotyl increased 400%, but that of cotyledon decreased 41% during 5 days cultivation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.1
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• pp.51-57
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• 2013

A demand for bio-diesel oil increases as one of solution for exhaustion of fossil fuel and reduction of $CO_2$ emission, and research on bio-diesel is being carried out. Bio-diesel oil is mainly esterified from vegetable oil with methanol in order to use for fuel on diesel engine and has demerit that costs are increased as compared with directly using like non-esterified one. Bio-diesel oil within 3% mixed with gas oil is used at present, proportion of bio-diesel oil will be increase by 5% in future. We judged that wasted soybean oil non-esterified could be used on diesel engine with an electronic fuel injection according to previous researches with a mechanical fuel injection. A performance test using only gas oil, gas oil with esterified bio-diesel oil 5% and wasted soybean oil non-esterified 5% on diesel engine with the electronic fuel injection were carried out. It is noticed that gas oil with wasted soybean oil non-esterified 5% has more similar characteristics to gas oil than gas oil with esterified bio-diesel oil 5%.