• Korean journal of food and cookery science
• /
• v.11 no.1
• /
• pp.20-25
• /
• 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 CROP SCIENCE
• /
• v.59 no.3
• /
• pp.359-363
• /
• 2014

Soybean seed is a good source of plant protein in human consumables such as baby formula and protein concentrate. The seeds contain an abundance of storage proteins, namely ${\beta}$-conglycin and glycinin that account for ~ 70-80% of the total seed protein content. Proteome profiling has been proved to be an efficient way that can help us to investigate the seed storage proteins. In the present study, the seeds were removed from the pods and the cotylendonary tissues were separated from the testa for proteome analysis in order to investigate the seed storage proteins. A systematic proteome profiling was conducted through one-dimensional gel electrophoresis followed by MALDI-TOF-TOF mass spectrometry in the seeds (cotyledonary tissue) of soybean genotypes. Two dimensional gels stained with CBB, a total of 10 proteins were identified and analyzed using MASCOT search engine according to the similarity of sequences with previously characterized proteins along with the UniProt database. A total of ten proteins such as glycinin Gy4 precursor, glycinin G3 precursor, glycinin G1 precursor, glycinin chain A2B1a precursor, glycinin chain A2B1a precursor were identified in our investigation. However, the glycinin subunit may be considered to play important roles in soybean breeding and biochemical characterization. In addition, the improved technique will be useful to dissect the genetic control of glycinin expression in soybean.

• Korean Journal of Food Science and Technology
• /
• v.31 no.3
• /
• pp.809-814
• /
• 1999

The effects of soybean extracts on serum lipid contents were evaluated in rats. Ninety-eight male Sprague-Dawley rats weighing $100{\pm}10g$ were divided into fourteen groups and fed different fat diets for four weeks. The experimental groups were divided into; control, saturated fat diet, unsaturated fat diet and high fat diet respectively were fed 1% cholesterol group. The serum total lipid were higher in saturated fat diet group than in control group. The contents of total-cholesterol in serum of the saturated fat diet group was significantly higher than other groups. The contents of HDL-cholesterol in serum of the soybean extract group were higher than those other fat diet group. The contents of LDL-cholesterol in serum of the soybean extract group were lower than other fat diet groups. The soybean extract group of lipid was significantly lower in other groups.

• Korean journal of food and cookery science
• /
• v.29 no.5
• /
• pp.525-531
• /
• 2013

Nutritional components and quality characteristics of drained soybean boiling water(DBW), which is discarded in the mass production of fermented soy foods, were compared with raw soybean(Control) and Cheonggukjang(CGJ) to provide the basic data for its recycle. The contents of moisture, crude protein, crude lipid and crude ash of DBW were shown as 87%, 2.2%, 0.15% and 1.42%, respectively. Decreased total amino acid of 1,677.8 mg/100g in DBW was comparable with 29,051.1 mg/100g in control, however, there was no great difference in the proportion of essential amino acid to the total. While the total sugar contents were decreased in both DBW and CGJ with 8.39% and 7.17% each from the control of 11.50%, the reducing sugars were increased with higher amount of 6.44% in CGJ and 8.30% in DBW than 5.60% in control. pH of DBW was lower than both of the control and CGJ. Hunter's color values revealed the increase of redness(a value) and yellowness(b value) of DBW and CGJ suggesting that Maillard reaction products were produced by the heating and fermentation process. Polyphenol compounds were highly abundant in CGJ of 0.74 tannic acid equivalent(mg/g) followed by similar low amounts of 0.33 and 0.29 tannic acid equivalent(mg/g) in DBW and control, respectively. Antioxidative activity determined by Electron Donating Ability(%) using DPPH radical showed that CGJ, of which polyphenols were the highest, has the strongest electron donating ability with the lowest $EC_{50}$ value of 5.91 mg/mL. DBW was much lower but similar with the control. From the above results the drained soybean boiling water was shown to have many nutritional and functional components as much as soybean, therefore, it could be a potent reusable food material.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.6
• /
• pp.917-924
• /
• 1995

Four types of soybean paste(Doenjang), prepared with traditional Korean meju, natto meju, koji and mixture of koji and natto meju, were analyzed for compositions of free sugars and fatty acids. Crude protein content of the soybean pastes were ranged from 10.3~14.6% and in the order of traditional Korean soybena paste>natto soybena paste>koji & natto soybean paste>koji soybean paste during fermentation of Doenjang. Ethyl alcohol contnet was relatively higher in koji and natto soybean paste after fermentation for 75 days, and its content was the highest in koji soybean paste as 2.8% after fermenting for 90 days. Contents of total sugars and reducing sugars decreased during fermentation of doenjang in the order of koji soybena paste>koji and natto soybean paste>traditional soybean paste>natto soybean paste. Among the free sugars glucose, galactose, mannose and arabinose were identified in soybean paste, and glucose and galactose were more bundant. Contents of glucose and total free sugars were the highest in the traditional Korean soybean paste and galactose content was highest in koji soybean paste. In fatty acid compositions of soybean pastes, palmitic, stearic, oleic, linoleic, linolenic and arachidonic acids were analyzed, and the most abundant fatty acid was found to be oleic acid as 38.5~46.9% in all samples tested. But no significant differences in ratio of fatty acid compositions was observed from tested samples during the fermentation period.

• Journal of the East Asian Society of Dietary Life
• /
• v.26 no.4
• /
• pp.325-333
• /
• 2016

This study investigated the proximate compositions and sensory attributes of fresh and boiled soybean sprouts. The sensory attributes of cooked soybean sprouts (Kongnamulmuchim) were also assessed after boiling and seasoning. Proximate compositions were analyzed from the total sprout, cotyledon and hypocotyl without hair root. Soybean sprouts cultivated with four recommended soybean cultivars (Nokchae bean, Dawon bean, Seonam bean and Pungsannamul bean) in a lab and then used for analysis. Carbohydrate, protein, lipid and ash contents were lower, while moisture was lower, in the cotyledon than in the hypocotyl of fresh soybean sprouts, regardless of the bean type. Each soybean sprout showed different contents of chemical constituents in total sprout, cotyledon, and hypocotyl parts. Sensory attributes such as odor, flavor, and overall acceptability were evaluated. Each panels showed a response on a 9-point rating scale. The acceptability of fresh soybean sprouts was negatively correlated with beany and grassy tastes, but positively correlated with nutty and sweet tastes. The acceptability of boiled soybean sprouts was negatively correlated with beany and grassy flavors, and positively correlated with nutty odor and flavor. In addition, acceptability of cooked soybean sprouts (Kongnamulmuchim) was positively correlated with nutty and sweet flavors. The beany and grassy flavors limited acceptability of fresh soybean sprouts, whereas the prominence of nutty flavor might contribute to acceptance of boiled and cooked soybean sprouts.

• Journal of the East Asian Society of Dietary Life
• /
• v.16 no.6
• /
• pp.717-723
• /
• 2006

Chemical characteristics of soybean oil after deep-frying with potato sticks (200 g, 10% w/w of soybean oil) were studied according to the 34 deep-frying times. After consecutive 34 deep-frying, total polyunsaturated FA contents was gradually decreased while the total saturated FA and trans FA were increased. Acid value and peroxide value were increased while iodine value decreased, respectively. The Hunter $L^{\ast}$ value decreased while each $a^{\ast}\;and \;b^{\ast}b$ value were gradually increased. Electronic nose equipped with 12 metal oxide sensors was used for the discrimination of odor pattern of frying oils against the times of deep-trying. The proportions of 1st and 2nd principal component analysis showed 75.97% and 21.23%, respectively. While 6 among total 12 sensors well responded to discrimination of odor in the repented frying oils, suggesting that the odor pattern of each oil after deep-frying would be discriminated against fresh soybean oil, especially after 14 times. From the results, electronic nose could differentiate the degree of quality deterioration of the repeated deep-frying oils.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.2
• /
• pp.313-318
• /
• 1998

This study investigated the effect of raw soybean yellow(RSY) and raw soybean black(RSB) on body weights, pancreas weights, serum glucose and lipid concentrations of boty normal and diabetic male rats(Sprague-Dawley, body weight 338.8$\pm$19.2g). For each experimental, some rats were injected with streptozotocin intraperitoneal(i.P.) to induce diabets, and other rats were injected with buffer i.P. as a control group. Body weight gain(BWG) was lower in rats fed both RSY and RSB diet(3.4~5.0g BWG) than in those fed control diet(58.1g BWG). The diabetic rats showed significant decrease of bo요 weight (-50~-67g) compared with the control rats. RSY and RSB feeding resulted in greater pancreatic weight relative to body weight, and diabetic rats fed RSY and RSB had heavier pancreatic weights relative to body weight than control rats. The levels of fasting serum glucose in diabetic rats fed both RSY and RSB decreased by 42 and 31%, respectively, compared with the diabetic control rats, but they increased by 80 and 110% compared with the normal control rats. The concentrations of total lipid, triglyceride, phospholipid and total cholesterol in serum of diabetic rats fed RSB diet were lower than those in control rats, but serum HDL-cholesterol, HDL-cholesterol/total cholesterol ratio were not affected by raw soybeans feeding. Atherogenic index wa lower in diabetic rats fed RSY and RSB diet than those in control rats. The concentrations of total lipid, triglyceride and phospholipid in liver were lower in raw soybean groups than those in control group. The concentrations of cholesterol in liver of groups treated raw soybean were decreased compared with the control group.

• Korean Journal of Plant Resources
• /
• v.26 no.2
• /
• pp.159-168
• /
• 2013

The study was conducted to determine the content of phenolics and flavonoids, antioxidant activity and antioxidant enzyme activity for the extract from 7 days old sprouts of cowpea (cv. "Seowon"), mungbean (cv. "Owool") and soybean (cv. "Pungsannamulkong"). Sprout length and weight of soybean sprouts were higher than those of cowpea and mungbean sprouts. Total phenolics content [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was highest in soybean sprout extracts (82.2 mg $kg^{-1}$), followed by cowpea (32.2 mg $kg^{-1}$) and mungbean (24.5 mg $kg^{-1}$) sprout extracts (p < 0.05). The result of total flavonoid level [mg rutin equivalents $kg^{-1}$ DW] had same tendency to the total phenolics, showing lower amounts. The antioxidant activity of the methanol extracts from all the plant dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was higher in cowpea (44%) and mungbean (42%) sprouts than in soybean sprouts (25%). Among antioxidant enzymes, APX and POX activities were highest in cowpea sprouts and CAT and SOD activities in soybean sprouts. The results showed that total phenolics content ($r^2$ = 0.5320 ~ 0.9032) and total flavonoids level ($r^2$ = 0.4672 ~ 0.9380) were highly correlated with antioxidant or with antioxidant enzyme activity, and that the level and activity of biologically active substances were different depending on plant species.

• Journal of Nutrition and Health
• /
• v.36 no.1
• /
• pp.32-39
• /
• 2003

Phytoestrogens, especially soy-derived isoflavones, are receiving great scrutiny as a food supplement for preventing hormone dependent disease such as postmenopausal osteoporosis. Their beneficial effects are derived from aglycone form of isoflavones, such as daidzein, genistein or glycitein. In contrast to the common usage of soybean, black bean (Rhynchosia Molubilis : Yak-kong) has been used as a supplement for preventing postmenopausal osteoporosis in oriental medicine. To investigate the effects of the saliva, artificial stomach fluid, and digestive enzymes on the conversion of glycosidic isoflavone to aglycone form, soybean and black bean were extracted with 70% methanol and freeze-dried. The recovery yield of methanol extracts of black bean was 14.1% which was higher than that of soybean, 13.5%. In terms of total isoflavones, we routinely obtained larger amount of isoflavones from black bean than those from soybean. By incubating methanol extracts of soybean and black bean with IN HCI for 180 min, the proportions of aglycones relative to the total isoflavone were significantly increased (32.4% and 52.4%, respectively). In vitro conversion, digestive enzymes ($\beta$-glucosidase and $\alpha$-glucosidase) may hydrolyze glycosidic bond of isoflavone more effectively than saliva or artificial stomach fluid did. It seems to say that the activity of $\beta$-glucosidase was higher than those of $\alpha$-glucosidase. The rate of conversion of glucoside form to aglycone form in black bean and soybean was low in physiological condition (pH) tested, although the enzymatic hydrolysis of glucoside was active. These results demonstrated that the composition of aglycone in food may be the important factors in terms of the bioavailability of isoflavones. (Korean J Nutrition 36(1): 32-39, 2003)