• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.255-261
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• 1993

The effect of dried soymilk residue (DSR) on protein quality of tofu was studied. The amount of added DSR into soybean water extract was corresponding 10% (dry basis) of soybean used in tofu manufacturing. Proximate composition and in vitro protein qualities of soybeans at different stages of the conversion into tofu have also been investigated. Partially substituted tofu with DSR (TDSR) had higher moisture content (80.6%) than that of tofu prepared in traditional manner (TT). TDSR contained lower content of protein (38.9%) and total lipid (26.9%) compared to 45.8% of protein and 34.3% of total lipid for TT. A large amount of trypsin inhibitor (TI) in raw soybeans was diminished and extracted through tofu processing, and only 10~13% of TI in raw soybean remained in both tofu products (TDSR and TT). There was not a considerable difference in amino acid profiles between TT and TDSR, but TDSR had a higher content of lysine than that in TT. in vitro studies showed that TDSR and TT were comparable in terms of both in vitro digestibilities (90% over for four-enzyme digestibility and predicted digestibility) and discriminant computed protein efficiency ratio (2.07~2.14, DC-PER). Unlike those in vitro indices for protein quality, computed protein efficiency ratio (C-PER) of TDSR was much lower (1.4) than that of TT (1.95). It was revealed that C-PERs of tofu products were not in agreement with rat-PERs (1.7~1.9) in previous reports except for TT. However, DC-PER assay was more recommendable for protein quality of tofu products than C-PER assay.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.262-265
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• 1993

Dietary fiber content and carbohydrate digestibility of dried soymilk residue (DSR) and tofu containing DSR were evaluated. Insoluble dietary fiber (IDF) content was 37.4 and 49.8% (%, moisture free basis) for common soymilk residue and DSR, respectively. Both soymilk residues contained 12.5% of soluble dietary fiber (SDF, dry basis). Tofu containing DSR, which is partially substituted with DSR corresponding to 10% weight of soybean used, had higher dietary fiber content (30% more for RDF and 45% more for SDF) than tofu manufactured in traditional manner. Carbohydrate digestibility was much lower in all tofu products ranging from 11% to 21%, and there was a negative correlation( r = -0.9243) between carbohydrate digestibility and total dietary fiber content.

• Resources Recycling
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• v.18 no.5
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• pp.52-62
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• 2009

This research was carried out to formulate environmentally friendly wood preservatives with okara and to investigate the effects of the acid concentration used for the hydrolysis of okara and salt type on the decay resistance of the preservatives. Okara-based preservatives were formulated with okara hydrolyzates, which were prepared with 0, 1%, and 2% sulfuric acid at $25^{\circ}C$ for 1 hr, and salts such as copper chloride and/or sodium borate. The preservatives were treated into wood blocks by vacuum-pressure method, and then the treated wood blocks were leached in $70^{\circ}C$ hot water for 72 hrs. The fungal treatments of the leached wood blocks were conducted by brown-rot fungus, Tyromyces palustris, and white-rot fungus, Trametes versicolor, to examine the decay resistance of the preservatives. As the acid concentration used for hydrolysis of okara increased, the treat-ability and decay resistance of the preservatives were improved, which the leachability was decreased. Wood blocks treated with the okara/copper or okara/copper/borax, showed very good decay resistance against T. palustris and T. versicolor. However, wood blocks treated with the okara/borax and okara-free preservative solutions, were observed the fungal decay by T. palustris. The optimal conditions for the preparation of okara-based wood preservatives were formulated with okara hydrolyzed with 1% sulfuric acid, copper chloride and borax.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.245-254
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• 2009

As a substitute for CCA, which is inhibited due to its environmental pollution and human harmfulness, and CuAz and ACQ with a high cost, okara-based wood preservatives were formulated with okara hydrolyzates using copper sulfate and/or borax as a metal salt. The efficacy of the preservatives and X-ray microanalysis of wood specimens treated with the preservatives were examined to confirm the potential of the okara-based wood preservatives. Most of the preservatives showed excellent decay resistance against brown-rot fungi, Postia placenta and Gloeophyllum trabeum. The efficacy was improved when the acid concentration and temperature used for the hydrolysis of okara increased. In addition, when borax was added into copper sulfate/okara hydrolyzates preservative formulations, any decay was not found in the specimens. From the microscopic observation of the specimens treated with okara-based wood preservatives, it seems that okara is contributed to the fixing of metal salts in wood blocks. Therefore, it is speculated that okara-based wood preservatives can effectively protect wood against fungal attack as CuAz, and that the preservatives are sufficient to use as an alternative wood preservative of CCA, ACQ and CuAz.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.77-81
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• 2005

To monitor GM soybean in soybean processed foods, tofu and biji, we prepared tofu and biji containing 0%, 1%, 3%, 5% and 100% GM soybean, respectively. We examined epsps gene inserted in soybean by PCR and EPSPS protein expressed in soybean using western blotting and lateral flow strip test to compare the sensitivity of these methods. A PCR product of 123 bp inserted in GM soybean was detected in all tofu and biji containing 1%, 3%, 5% and 100% GM soybean with the exception of 0% samples; however, the size of 600 bp inserted in GM soybean was only detected in tofu containing 100% soybean and in biji containing 5% and 100% soybean. In the protein level, GM soybean product was only detected in tofu and biji containing 100% GM soybean by western blotting. In addition, only biji containing 100% GM soybean was detected by lateral flow strip test. We concluded that in order to detect GM soybean efficiently in processed food, the PCR method is more sensitive than immunological methods. With the PCR method, small size product with approximately 100 bp in PCR product is sensitive to detect GM soybean in processed foods.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.30-38
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• 2008

Petroleum-based resin adhesives have extensively been used for the production of wood panels. However, with the increase of manufacturing cost and the environmental issue, such as the emission of volatile organic compounds, of the adhesive resins, it is necessary to be developed new adhesive systems. In this study, the potential of okara, which is a residue wasted from the production of tofu, for the development of bio-based adhesives was investigated. At first, the physical and chemical properties of okara were examined. After okara was hydrolyzed in acidic and/or alkaline solutions, okara-based adhesive resins were formulated with the mixtures of the okara hydrolyzates and phenol formaldehyde (PF) prepolymer. The adhesive resins were used for the fabrication of plywood panels, and then the adhesive strength and formaldehyde emission of the plywood panels were measured to examine the applicability of the resin adhesives for the production of plywood panels. The solids content and pH of the okara used in this study were around 20% and weak acidic state, respectively. In the analysis of its chemical composition, the content of carbohydrate was the highest, and followed by protein. The shear strengths of plywood fabricated with okara-based resin adhesives exceeded a minimum requirement of KS standard for ordinary plywood, but its wood failure did not reach the minimum requirement. In addition, the formaldehyde emissions of all plywood panels were higher than that of E1 specified in the KS standard. Based on these results, okara has the potential to be used as a raw material of environmentally friendly adhesive resin systems for the production of wood panels, but further researches - biological hydrolysis of okara and various formulations of PF prepolymer - are required to improve the adhesive strength and formaldehyde emission of okara-based resin adhesives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.673-677
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• 1993

The effects of soybean products(bean curd and curd residue) on the cholesterol profiles of serum and liver were studied in rats. Male rats were fed on purified diets, supplemented with cholesterol, containing casein (CAS), dried bean curd(DBC), or mixture of casein and dried bean curd residue(CBCD, 3:1, w/w) as a protein source for 4weeks. Dietary DBC and CBCD, compared with CAS, reduced markedly the concentration of serum cholesterol. The concentration of HDL-cholesterol was significantly higher in the CAS group than in the CBCD group, but there were no significant differences in the ratio of HDL-cholesterol to total cholesterol. Liver cholesterol was lower in the DBC group than in the CAS and CBCD groups. The results suggest an effective cholesterol-lowering action of soybean products in rats fed on cholesterolemic diets, and further a possibility that than curd dreg decrease the concentration of serum cholesterol, regardless of the presence of animal protein in diets.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.271-276
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• 2000

A amylase producing bacteria were isolated from tofu residue and identified as Bacillus sp. according to the morphological and biochemical properties, which were named Bacillus sp. GM7330 and Bacillus sp. GM7312. The cultural condition for the production of amylase was showed on 5% tofu residue added 3% glucose and 0.15% yeast extract. And incubated during 72 hrs at 30。C, Bacillus sp. GM7330 and Bacillus sp. GM7312 were producing amylase of 488 units and 341 units.

• Proceedings of the Culinary Society of Korean Academy Conference
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• 2002.04a
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• pp.42-78
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• 2002

ㆍ 제주전통두부 제조에 따른 지역별 원료대두의 전처리 공정은 \circled1 생두부 -> 수침 -> 맷돌분쇄, \circled2 생두부 -> 맷돌분쇄 -> 수침 그리고 \circled1과 \circled2를 병행한 방법이 있었다. ㆍ비지제거공정의 경우 비지를 제거하는 지역과 비지를 제거하지 않는 지역(성읍)이 있었으며, 비지분리를 위한 첨가제로 돼지기름(내도) 또는 돼지기름과 쌀겨를 혼합(선흘)한 경우가 있었으며, 비지분리 횟수는 지역에 따라 1~3회 정도의 차이가 있었다. ㆍ 가열공정 중 가열용기는 가마솥을 사용하였고, 누름방지제로는 대부분의 지역에서 돼지기름을 사용하였고 일부 지역에서는 들기름을 사용하였다. ㆍ 응고공정 중 응고제로 해안선 지역에서는 해수를 사용하였고, 중간산 지역에서는 소금물을 이용하였으며, 염전이 있는 지역에서는 간수를 사용하였다. ㆍ 성형시간은 60~720분이었으며, 냉각은 수냉이 아닌 방냉을 하였다. 제주 전통두부는 주로 잔치, 상례, 기제사, 명절 등 대소사에 사용하였으며 대부분 가열조리하지 않고 섭취하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1431-1435
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• 2007

Soybean curds were prepared by adding different levels (20, 40, and 60%) of small black soybean, and the quality characteristics of the soybean curds were investigated. The yield of soybean curd increased slightly with the increment of the levels of small black soybean, whereas L value (lightness) and b value (yellowness) decreased. Analysis of textural properties demonstrated that the addition of small black soybean lowered the hardness and chewiness of soybean curd, while it slightly increased the cohesiveness and adhesiveness. Antioxidant activities of soybean curd, soybean curd residue, and soybean curd whey were estimated by determining electron donating ability (EDA) to DPPH radical and superoxide dismutase (SOD)-like activity. These activities in all of the samples increased with the addition of small black soybean, especially in soybean curd residue and soybean curd whey; also, soybean curd whey containing small black soybean showed the highest activities.