• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.249-254
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• 1996

두유에 해조류 마쇄물을 10% 혼합하여 두부를 제조하고 일반두부와 품질특성을 비교하였다. 모자반, 미역, 다시마를 첨가한 두부는 일반두부에 비하여 수율과 단백질, 회분 함량이 각각 19.6~20.6%, 3.1~7.1%, 10.8~21.4% 증가하였고 두유청의 탁도는 감소하였다. 해조류 첨가 두부의 견고성은 0.36~0.52kg으로 일반두부의 0.70kg에 비하여 낮았으나 탄력성, 응집성, 부서짐성은 현저히 증가하였고 껌성도 증가하였다. 해조류 첨가로 두부의 색도중 L값은 낮아졌고 a값은 미역과 다시마 첨가구에서, b값은 톳 첨가구에서 가장 낮았다. 해조류 첨가 두부는 응고제 첨가량의 증가로 Ca 함량이 현저히 증가하였으며 Fe, Zn, Mn은 감소하였다. 두부의 조직감은 다시마와 꼬시래기, 톳을 첨가한 두부가, 맛은 꼬시래기를 첨가한 두부가 양호하였다.

• Food Science and Preservation
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• v.21 no.2
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• pp.215-223
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• 2014

The quality characteristics and antioxidant activity of three kinds of tofu made from lipoxygenase (LOX)-free genotypes soybeans were compared to the Taekwang (LOX-present) tofu as the control. The mineral contents of Jinyang tofu were significantly higher than those of the control. The hardness and gumminess of tofu made from LOX-free genotypes were significantly higher than those of the control. Gaechuck#2 tofu showed higher sensory evaluation results than the other kinds of tofu in terms of taste, flavor and overall acceptability. The total isoflavone contents were higher in the LOX-free genotypes than in the control. The total phenol content was similar for the Gaechuck#1, #2 and Taekwang tofu. The flavonoid content was higher in Gaechuck#1 and #2 tofu than in the control. The antioxidant activities were the highest in Gaechuck#1 tofu, followed by the Gaechuck#2. During the 15-day storage at $4^{\circ}C$, the turbidity of the immersing water tended to increase, but Gaechuck#1 and #2 tofu were significantly lower than in the control after 15-day storage. Therefore it is suggested that Gaechuck#2 tofu could be the suitable genotype for tofu products because it is the most effective in terms of overall acceptability, antioxidant activity, and storage stability.

• Journal of the Korean Society of Food Culture
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• v.21 no.6
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• pp.653-660
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• 2006

Some quality characteristics of tofu prepared with cuttlefish ink were investigated to study the effects of various of coagulants. Each concentration of coagulant was determined as 0.2% of GDL, 0.3# of $MgCl_2$, 1%^ of $CaCl_2$, 1.5% of $CaSO_4$ and 0.6% D-gluconic acid calcium by pre-experiment. Also, the optimum concentration of added cuttlefish ink was chosen as 3%(diluted in twenty times). The yield of inky tofu prepared with GDL as coagulant was the highest. According to prepared with $MgCl_2$ was the highest. The result of microstructure was examined by SEM, the particles of inky tofu coagulated with GDL and D-gluconic acid calcium were small and uniformity. In overall acceptability of sensory properties, inky tofu coagulated with GDL was the highest in score. In the color of inky tofu, L value and a value were the highest coagulated with GDL, but that coagulated with $CaCl_2$ had the highest b value. In the texture properties of inky tofu, hardness, gumminess and brittleness were the highest coagulated with D-gluconic acid calcium. A positive correlation was observed between the pH of tofu whey and acidity. Sensory properties of roasted nutty flavor, hardness, cohesiveness and springiness were positively correlated with the acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.9-14
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• 1984

This research aims to increase the extent of utilization of soybean curds coagulated with $Glucono-{\delta}-lactone$ (GDL) as a protein soarce by analyzing nutritive guality and preference to them. The curds were made from two kinds of soybean, domestic and imported. The results were as follows; 1. The yield of the domestic soybean curd was higher than that of the imported. 2. The total nitrogen and amino acid content of the GDL soybean curd were higher in the do- mestic while lipid and ash were higher in the imported one. 3. Rheological properties such as hardness, toughness, springiness and chewiness were higher in the domestic soybean curds than those of tile imported. 4. The 'L' values of the GDL soybean curds were higher in the domestic. However, there were no significant differences in the 'a' and 'b' values between the domestic and the imported soybeans. 5. According to the organoleptic the GDL soybean curds were not so favorable to our preferences .

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.633-637
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• 2005

The effects of adding hull powders of black soybean on quality characteristics of tobu were studied. Proximate composition of the black soybean hull powders was crude ash, crude protein, crude fat, and carbohydrate at 2.60, 11.35, 2.18, and 73.97%, respectively. The addition of 5% black soybean hull powder decreased the production of whey and consequently increased the yield of tobu. Texture properties of evaluation hardness, adhesiveness, chewiness were the best in tobu which was made with 5% black soybean hull powders. Sensory evaluation showed texture, firmness were not significantly different among tobu with yellow soybean, black soybean, and added to 0.5% black soybean hull powders. At the beginning of the period of storage, there were not differences of microbial cell count as increasing black soybean hull powders, but observed after passing 5 days. The results of total microbial cell count showed that adding 5% black soybean hull powders in processing tobu extend storage time.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.78-85
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• 1997

To determine the optimum coagulants concentrations for preparing soybean-curds, the transmittance of soybean-curd whey using spectrophotometer has been measured. The textural properties of soybean-curds were examined by texture analyzer and sensory evaluations. The general components, oligosaccharides and amino acids in soybean-curd wheys were analyzed. Protein patterns of soybean-curd wheys comparing with soyflour and soymilk were investigated. By texture analyzer, hardness, cohesiveness, springiness, and gumminess of Cacl$_2$ soybean-curd, MgCl$_2$ soybean-curd were higher than those of CaSO$_4$ soybean-curd and GDL soybean-curd. In the sensory evaluations, CaSO$_4$ soybean-curds and GDL soybean-curds were smoother and moister than others. Glutamic acid and aspartic acid were the first two abundant amino acids in three kinds of soybean-curd wheys, but arginine was the most abundant amino acid in GDL soybean-curd whey. Total sugar content of soybean-curd wheys were about 12-13 g/l, and the main sugars among 5 kinds of sugars were sucrose and raffinose. Electrophoresis using SDS-PAGE showed that glycinin and P-conglycinin, the main proteins of soybean appeared in soy flour and soymilk, and only low molecular weight subunits appeared in soybean-curd wheys.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.649-656
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• 2011

In this study, we made Sulgidduk with commercialized dried nonglutinous rice flour and different levels of soybean curd. For physical properties of the bean curd-Sulgidduk, its water content was increased significantly with a growing addition of soybean curd. In chromaticity, its L value(brightness) and a value(redness) were decreased significantly with more bean curd while b value(yellowness) went up in Sulgidduk with a large amount of rice flour but went down significantly in the Sulgidduk with a small amount of it. Its hardness of texture was found to be the highest in the Sulgidduk with the most dried nonglutinous rice flour and it tended to be higher with more rice flour and less soybean curd. For cohesiveness, it was recorded to be the highest in the Sulgidduk without soybean curd and showed a tendency of decreasing by adding the bean curd but increased later significantly. In addition, its springiness and brittleness became larger with addition of more dried nonglutinous rice flour. From these results, the best ratio of the bean curd-Sulgidduk to increase nutrition and absorption and to satisfy physical and sensory properties, was 420 g to 500 g of soybean curd to dried nonglutinous rice flour. Moreover, it was considered to decline the calorie of Sulgidduk by adding soybean curd as a material and to contribute to its commercialization by extending storage and preservation time of soybean curd with a short expiration date.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.22-27
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• 2006

This study was carried out to determine the optimum conditions for making soybean curd(or tofu) from defatted soybean flour.. Heating soymilk above $80^{\circ}C$ for at least $5{\sim}10\;min$ was necessary for soybean protein to form aggregates during subsequent coagulation process with glucono-${\delta}$-lactone(GDL). For maximum yield of tofu, with water content of approximately 80%, extra addition of 20 g of oil and 5 g of GDL per 425 g of soybean flour was needed. Maintaining soymilk temperature around $75^{\circ}C$ for 5 min was necessary when GDL was used as the coagulant.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.117-121
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• 2009

Soybean curd (SC) is prepared through the elimination of water-insoluble components and molding by pressing. However, whole soybean curd (WSC) is made without the elimination of water-insoluble components and pressing. Therefore, it was considered that the components contained in WSC might be different from those in SC and we compared their contents of various components, hardness, and morphological features for this study. Ash, dietary fiber, and niacin contents were significantly higher in WSC than in SC. In addition, the carbohydrate and vitamin $K_1$ contents of WSC tended to be higher than those in SC, whereas the hardness of WSC was lower than that of SC. Moreover, electron microscopic analysis showed that the morphological characteristic of WSC consisted of considerably more fine retiform tissues in comparison to SC. Based on their compared nutrition, functional, and quality characteristics, it was suggested that WSC might be superior to SC.

• Food Science and Preservation
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• v.20 no.5
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• pp.636-642
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• 2013

Quality and sensory characteristics of tofu prepared with concentrated to 8 $^{\circ}Brix$ deep ground sea-like water (SW) were investigated to check the availability for coagulants. The tofu was coagulated with three kinds of commercially coagulant, such as $MgCl_2$, $CaSO_4$ and glucono-${\delta}$-lactone. Different amounts of SW and soybean milk were added: SW-20 g/L, SW-25 g/L and SW-30 g/L. The moisture content and pH were significantly lower in which preparation with glucono-${\delta}$-lactone coagulated tofu, and others has not significantly difference each other. The mineral contents in the coagulant influenced the mineral content of the tofu, which contained larger quantities of major minerals. However, the mineral content of the tofu was not affected of the mineral concentration in the coagulant. The L and b values of the tofu prepared with SW were not significantly different. The hardness of the tofu prepared with the commercial coagulants was significantly lower than that of the tofu produced with the SW. The sensory property was lower when the hardness was lower and higher. In conclusion, the quality characteristics of SW-prepared tofu were not significantly different from those of the tofu prepared with the commercial coagulants, but the texture and the taste of the SW-prepared tofu were excellent.