• Korean journal of food and cookery science
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• v.15 no.4
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• pp.382-387
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• 1999

This study was conducted to investigate the changes of mineral contents in radish leaves, soybean sprout and chwi namul by cooking method(boiling, steaming, sauting) and cooking time(1, 3, 5 min.). The residual rate of minerals(such as Calcium, Sodium, Potassium, Iron and Magnesium) in radish leaves, soybean sprout and chwi namul by 1 minute sauting was the range of 83.2 to 99.1%. It was shown that sauting was desirable method for all three vegetables. The residual rate by the cooking method was sauting, steaming, boiling, in that order, but boiling in radish leaves and chwi namul were more desirable method than steaming for Calcium use. At the cooking method and cooking time, Potassium content in soybean sprout was reduced remarkably in 5 minutes boiling. Boiling of radish leaves and soybean sprout showed that Sodium was reduced remarkably after 5 minutes of boiling, 54.4% for radish leaves and 19.9% for soybean sprout, respectively.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.6-10
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• 2005

The trypsin inhibitor activity (TIA) of various soybean cultivars was evaluated by measuring the inhibition of trypsin activity using N-benzoyl-DL-arginine-p-nitro-anilide (BAPNA) as the substrate. The TIA values of eleven white shelled soybean cultivars including a glyphosate-tolerant soybean (16.58 to 17.90㎎/g) were not significantly different among cultivars. Black shelled soybeans had higher TIA values, ranging from 40.09 to 52.11㎎/g, compared to white shelled soybeans (p<0.05). When the TIA of commercially processed soybean foods were determined, no TIA was detected in soysauce, tofu and soybean paste. During conventional moist heating, the IT/sub 50/ (Time required to reach 50% inhibition of TIA) values were decreased as heating temperature and cooking pressure increased. The IT/sub 50/ values of moist heating were estimated to be 91.68, 37.71 and 19.50 min at 60, 80 and 100℃, respectively. The IT/sub 50/ value of microwave cooking was 4.75 min at medium heat, while that of the pressure cooking at 120℃ was only 2.62min. Moreover, there was a negative relationship between temperature and IT/sub 50/ values (R=0.92, p<0.01). The TIA of soybean sprouts was completely inactivated after heating at 100℃ for 5 min, although fresh soybean sprouts showed one fifth of the TIA value of white shelled soybeans. Based on our results, pressure cooking is the most effective cooking method to reduce TIA in soybeans.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.91-95
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• 2006

Effects of cultivars, cooking, and processing on hemagglutinin activity were evaluated by observing macroscopic hemagglutination using serial twofold dilution of trypsinized human blood type-O or rabbit blood. Hemagglutinin activity was expressed as maximal geometric dilution fold. Agglutination of rabbit blood was more sensitive compared to human blood. Hemagglutinin activities of glyphosate-tolerant soybean, HS2906, and imported conventional soybeans were not statistically different, although significant differences were observed among conventional soybean cultivars cultivated in Korea (286 to 1535 HU/mg protein). Time required to reach fifty percent inhibition of hemagglutinin activity ($IT_{50}$) value decreased with increasing cooking temperature and pressure. Most effective conventional cooking method to inhibit hemagglutinin activity was pressure-cooking ($IT_{50}$: 1.36 min). Calculated activation energy based on reaction rate constant was 4.88 kcal. No hemagglutinin activities were detected in processed soybean products such as tofu, soybean paste, and soysauce.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.20-25
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• 1995

The effects of cooking on the dietary fiber content in rice, brown rice, yellow soybean and black soybean were investigated. The dietary fiber contents were analyzed by Prosky's method(AOAC method) after boiling, microwave heating and autoclaving of the sample. It was showed that the different cooking methods resulted in different effects on the insoluble dietary fiber contents. Except yellow soybean, cooking time had little effect on insoluble dietary fiber contets in the other samples. The contents of soluble dietary fiber were generally increased by cooking. Increased cooking time reduced the content of soluble dietary fiber in brown rice but increased in rice. However, no significant differences caused by cooking time were observed for soluble dietary fiber in black soybean. The effects of cooking method on the total dietary fiber contents were similar to those of insoluble dietary fiber. The reasons for this might be that the main fraction of total dietary fiber was insoluble forms and the content of total dietary fiber was calculated as the sum of insoluble and soluble dietary fiber content.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.372-375
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• 1986

The temperature dependence of the cooking rate of soybean cotyledon was investigated by cooking samples at $106^{\circ}C-121^{\circ}C$ and by measuring the maximum cutting force. The cooking of soybean followed a first-order reaction and the reaction rate constant was approximately doubled by increase of cooking temperature by 4 or $5^{\circ}C$. The z-value for softening of the soybean, which was calculated from the time-temperature combinations that gave the same degree of cooking, was $13.3^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.522-526
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• 1997

Soy isoflavones could be recovered with adsorption resin column chromatography from soybean cooking water produced during soymilk or tofu manufacturing process. The main isoflavones in the soybean cooking water were genistin and daidzin, and their concentration was $0.083{\pm}0.019$ and $0.11{\pm}0.017\;mM$, respectively. Their aglycones were not detected. pH of soybean cooking water was critical in this chromatographic process and the recovery of isoflavones, both genistin and daidzin, was maximum at pH 4.0. Adsorption of genistin on the resin was stronger than that of daidzin. Elution rate and height/diameter ratio also affected the recovery yield. Under the optimal conditions, about 85% of genistin and 70% of daidzin could be isolated from soybean cooking water. Soy saponins were also recovered with isoflavones.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1138-1144
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• 2009

This study was carried out to investigate the cooking properties and lipid oxidation stability during storage at $4{\pm}1^{\circ}C$ when the various levels (5 to 20%) of doenjang (Korean fermented soybean paste) were added to pork patties cooked by pan frying (PF) and convection oven (CO). With increasing the addition of doenjang, cooking properties of pork patties revealed the improved cooking yield, less diameter reduction, and less thickness increase. Also, the shear force, hardness, and chewiness of pork patties were reduced. The PF cooking method showed better cooking properties than CO. Lipid oxidation expressed by the thiobarbituric acid reactive substances (TBARS) values was significantly reduced by the addition of more than 5% doenjang (p<0.05). The TBARS values of cooked pork patties by PF were significantly lower than CO during the 8 days of the storage (p<0.05). The development of warmed-over flavor (WOF) in cooked pork patties was delayed as the amount of the doenjang was increased. It was suggested that the addition of doenjang and PF favorably affected the cooking properties and stability of lipid oxidation in pork patties.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.219-226
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• 2018

The purpose of this study was to investigate the effect of thermal treatments, such as a sous-vide and a conventional hot water cooking, on the texture changes of soybean sprout. A novel method to measure texture properties of soybean sprout have been determined because of the irregular geometry of soybean sprout. The shape of cotyledon of bean spout was accurately analyzed using an image processing and a geometry model. To minimize the effect of the contact area on the texture measurement, a blade type of probe was selected for the measurement. True stress was evaluated to reflect the shape changes during deformation, and demonstrated that the measurement accurately distinguished the effect of thermal treatment on the texture. Different heating time (i.e., 0, 10, 20, and 30 min) was applied for both sous-vide and conventional cooking. Thermal processing caused hardening of textures for both cotyledon and hypocotyl of soybean sprout. The conventional cooking method showed higher stress values than those of sous-vide cooking. Sprouts cooked by sous-vide released the moisture after thermal processing while sprout cooked by a conventional water bath method could hold the moisture content during thermal processing. The soybean sprouts treated by conventional cooking method showed a higher score in sensory evaluation.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.299-308
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• 2020

This study investigated the quality characteristics of black soybean sediments to diversify the availability of soybean. The cooking method selected for black soybean sediment preparation was a pressure cooking process without soaking, considering the isoflavone content. The black soybean sediments were prepared by the addition of 0, 10, 30, 50 and 100% (w/w) black soybean. When 0% to 100% black soybean was added to the black soybean sediments, the moisture and crude protein contents increased from 53.17% to 54.41% and from 12.07% to 21.68%, respectively. The total isoflavone content of the black soybean sediments was increased from 2.69 ㎍/g to 696.09 ㎍/g, respectively, by the addition of black soybean. The anthocyanin content of the black soybean sediments ranged from 279.29 ㎍/g to 387.8 ㎍/g by the addition of black soybean. The total polyphenol content and the total flavonoid content of the black soybean sediments range from 1.72 mg/g to 2.00 mg/g and 0.89 mg/g to 0.92 mg/g, respectively, by the addition of black soybean. Given the isoflavones, total polyphenol, and anthocyanin content of the black soybean sediments, it is appropriate that the ratio of added black soybeans is at least 50% after the pressure-cooking process, regardless of soaking.

• Food Science and Preservation
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• v.7 no.4
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• pp.384-388
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• 2000

This study was carried out to investigate the optimal process conditions of instant soybean soup for the soybean noodles. The process of soybean soup was in the other or soaking, cooking, peeling, drying, milling and packaging. The optimal conditions of soaking process obtained at 25$\^{C}$ for 4hrs, and the protein content of yellow and black soybean after soaking treatment were 21.97% and 19.58%, respectively. As the increasing of cooking time, the moisture content was not changed, and optimal cooking condition through the sensory evaluation was obtained at 100$\^{C}$ and 15min. The protein contents of cooked yellow and black soybean dried by hot-air and far infrared-ray were 43.40∼44.18% and 44.59∼51.36%, respectively. From the results of sensory evaluation, the yellow and black soybean dried with far infrared-ray at 45$\^{C}$ for 5hrs were excellent, and the difference between the marketed soybean soup and instant soybean soup produced by this experimental process for soybean noodles was not exist. The optimal concentration of instant soybean soup for soybean noodles was determined to be 50g of soybean powder with 1L water.