• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.388-396
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• 2009

In our study, the potential of okara as an ingredient of new bio-based adhesives was investigated for the production of fancy-veneered flooring boards. Okara was hydrolyzed by 1% sulfuric acid solution (AC) and 1% sodium hydroxide solution (AK). Phenol formaldehyde (PF) prepolymers were prepared as a cross-linker of okara hydrolyzates. Then, okara-based adhesive resins were formulated with 35% AC, 35% AK and 30% PF prepolymer on solid content basis. The adhesive resins were applied on high-density fiberboards (HDF) with the spread rate of $300g/m^2$. After that, oak fancy veneers are covered on the HDF, and then pressed with the pressure of $7kg/m^2$ at $120^{\circ}C$. The experimental variables were three mole ratios of formaldehyde to phenol (1.8, 2.1, 2.4), three assembly time (0, 10, 20 min), and two press time (90 sec, 120 sec), respectively. The fancy-veneered high-density fiberboards were tested by dry tensile strength, glueline failure by wetting and formaldehyde emission. Tensile strength of the boards exceeded the requirement of KS standard. The formaldehyde emissions were approached at the E0 level specified in KS standard. Based on these results, okara can be used as an ingredient of environmentally friendly adhesive resin systems for the production of flooring boards.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.522-525
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• 1985

The dried soymilk residue (SMR) was added into soybean water extract in order to investigate its effect on physical characteristics of soybean curd. As the mixing ratio (d. b.) increased, the volume and water holding capacity of the curd was reduced and penetration value was increased. However, the Sag value was rather increased until 20% of mixing ratio reached and then decreased drastically by 30% addition of SMR. The overall physical and sensory quality showed that substitution of soybean with SMR by 10% was recommendable without significant unfavorable change in quality of soybean curd. The proposed method of absorption of unbound water on filter paper was proved to be simple and reliable for measurement of water holding capacity of soybean curd.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.484-489
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• 1994

Solubilization of plant ceil wall(tofu-residue) using enzyme complex obtained by Aspergillus niger CF-34 was attempted. The hydrolysis reaction was done at pH 4.0, $50^{\circ}C$, which were optimum pH and temperature of the enzyme, respectively. At the enzyme dosage of 2.5% (in terms of solid content of tofu-residue) and reaction time of 3 hr, the solubilizing percent of protein and carbohydrate were 62% and 50% respectively. Homogenization prior to enzyme reaction did not have much effect on tofu-residue solubilization. To improve solubility of tofu-residue, additional treatment such as alkali with 0.1% NaOH solution was found to be useful. The results showed that tofu-residue, which mainly consists of cell wall component of cellulose and hemicellulose, was not accessible to enzyme reaction and some prior treatment is required to enhance enzyme hydrolysis.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.490-495
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• 1994

Enzymatic solubilization of tofu-residue was attempted using carbohydrase isolated from Aspergillus niger CF-34. Tofu-residue, by-product of tofu manufacture or soymilk processing was used as the model for plant cell wall. It was found that tofu-residue was rich in nurients: 46.7% carbohydrate, 32.8% protein, the rest being lipid and ashes. Carbohydrate component of tofu-residue consisted of 36.8% cellulose and 62.6% hemicellulose. The carbohydrase was found to consist of pectinase, xylanase, PGase, CMCase, and SFase when tofu-residue and pectin were used as the carbon source. Enzyme induction was maximum at 7days of culture. Optimum reaction pH was 4.0, temperature $50^{\circ}C$. The enzyme was stable to $50^{\circ}C$, above which the stability decreased rapidly.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.110-123
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• 2008

The use of CCA as a wood preservative was recently inhibited due to its environmental pollution and human harmfulness. Instead of CCA, copper azole (CuAz) and alkaline copper quaternary (ACQ) have been used as alternative wood preservatives, but the price of the preservatives is much more expensive than that of CCA. As a substitute for high-priced CuAz and ACQ, environmentally friendly wood preservatives were formulated with okara, which is an organic waste from the production of tofu. Prior to formulating the preservatives, okara was hydrolyzed by three levels of sulfuric acid concentration (1, 2.5 and 5%) to easily penetrate the effective components of the preservatives into wood blocks. Final preservative solutions were formulated with the hydrolyzed okara and metal salts, such as copper sulfate, copper chloride and borax. The preservatives were treated into wood blocks by vacuum-pressure method to measure the treatability of the preservatives, and the treated wood blocks were placed in hot water for three days to measure the leachability of the preservatives. The effective components of the preservatives might be successfully penetrated into wood blocks through the uses of hydrolyzed okara and ammonia water. However, the leached amount of effective components was increased as the concentration of acid used for the hydrolysis of okara increased. The treatability and leachability of the preservatives were not affected by hydrolysis temperature but negatively affected by the addition of borax. Based on the results above, the optimal conditions for formulating okara-based wood preservatives cost-effectively and environmentally might be 1% acid hydrolysis of okara and the use of $CuCl_2$ as a metal salt. In addition, the treatability and leachability of okara-based wood preservatives were superior or no differences comparing with those of CuAz. Therefore, it is concluded that okara-based wood preservatives might have a potential to be used as an environmentally friendly wood preservative.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.2
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• pp.9-16
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• 1999

Edible films were prepared from proteins extracted from soybean curd residue by alkaline extraction and isoelectric precipitation. Effects of film forming solution pH and plasticizers on mechanical and barrier properties of edible films were studied. films were formed within pH $7{\sim}11$ with tensile strength (TS) of $2.9{\sim}3.3$ MPa. Films produced under pH 10 had the highest TS and Elongation (E) (3.3 MPa and 60.1%) but no significant difference was observed among water vapor permeabilities (WVP) of film. Glycerol, sorbitol and its mixture (1:1, w/w) were added as plasticizers. The concentration and mixing ratio of plasticizers also affected the TS, E and WVP of films. TS of films decreased from 15.0 MPa to 2.9 MPa as plasticizer concentration increased from 0.4 to 0.8 g plasticizer/g protein. At a plasticizer concentration, the highest TS was observed when sorbitol was used whereas the highest E was measured when mixture of glycerol and sorbitol was used as plasticizer WVP of films increased as the plasticizer concentration increased. Films plasticized with glycerol showed the highest WVP among the films with the same plasticizer concentrations. Edible films prepared from soybean curd residue protein showed very low oxygen permeabilities ($29.5{\sim}61.1aL{\cdot}m/m^2{\cdot}s{\cdot}Pa$) and oil resistance at all plasticizer concentration level tested.

• Food Science and Preservation
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• v.10 no.3
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• pp.360-364
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• 2003

This study was conducted to investigate the preparation possibility of Beni-koji by Monascus pilosus using dried soybean curd residue(Biji). The additional effect of water(0-50％), glucose(0-10％, w/w), monosodium glutamate(0-0.l％, w/w) and citrus peel water extracts (0-0.5％, v/w) on the pigment and monacolin K content of the Biji Beni-koji were examined. Optimal added amounts of water was 20％ of dried Biji. The highest pigment content(OD at 500 nm) of Biji Beni-koji was 1.06 in 10％ glucose, 2.26 in 0.01％ monosodium glutamate and 2.61 in 0.4％ citrus peel water extracts. The content of monacolin K in the Biji Beni-koji added with 10％ glucose, 0.01％ monosodium glutamate and 0.4％ citrus peel water extracts showed 96.38 mg％(w/w), 118.25 mg％(w/w) and 104.50 mg％(w/w), respectively.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.235-236
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• 2003

양식에 있어 사료는 총 생산비의 절반 이상을 차지하기 때문에 대상 어종을 위한 배합사료 개발은 생산성과 경제적인 측면에서 가장 우선적으로 고려되어야 한다. 배합사료의 가격은 배합원료 단가, 영양소의 종류와 균형에 따라 달라지는데, 경제적으로 배합되어야 할 원료의 선정이나 적정 첨가범위 등을 설정하는 연구는 경제적인 면에서 매우 중요하다. 사료에 첨가되고 있는 원료에는 식물성과 동물성이 있으며, 식물성 원료로는 대두박, 콘글루텐 밀, 아마박 등이 있고, 동물성으로는 어분, 육분, 혈분, 우모분 등이 있다. (중략)

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.74-80
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• 1999

Growth and bacteriocin production by Lactobacillus sp. GM7311 in tofu residue treated with two commercial amylases were investigated. The optimal condition of amylase Ⅰ(liquefied enzyme for sauce) and Ⅱ(multienzyme 2,000) for the enzyme reaction was showed at pH 6.0 and 4.0, respectively. The optimal temperature was 40oC both. At the enzyme dosage 4% and 3% and reaction time 1hr, about 2% of reduced sugar needed bacteriocin production was obtained. The enzymatic treatment of tofu residue enhanced bacteriocin production by lactic acid bacteria, particularly in the tofu residues added 2.0% yeast extract. But, we couldn't see the increment of bacteriocin activity in the tofu residues added other nitrogen sources such as proteose peptone No. 3 and lab lemco powder. Also, in the comparision of amylase I and Ⅱ, bacteriocin activity in the tofu residue treated with amylase Ⅰ was better than that of amylase Ⅱ.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.723-727
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• 2004

Qualitative and quantitative PCR methods were performed to examine detection and quantitation of epsps inserted into genetically modified soybean (GMS) in processed foods, soy milk, tofu, and biji (soybean curd residue). Using PCR amplification to produce two (121 and 330 bp) epsps in GMS, detection limits of GMS in soy milk, tofu, and biji containing 0.01% GMS were measured. For quantitative detection, test samples containing 1, 3, and 5% GMS were measured by real-time PCR method. Results show real-time PCR method is applicable to detect GMS quantitatively in processed foods.