• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.381-386
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• 1985

This experiment was conducted to investigate changes of soybean curd yield according to the extension of soaking time during manufacturing of soybean curd. To investigate those changes systematically, transmission electron microscopy and disc-gel electrophoresis were used. The soybean curd yield was increased from 45.0% to 50.5% and 55.4% respectively as soaking time is extended from 5 hours to 10 and 24 hours. The solid extraction and soybean milk coagulation were also increased according to the extension of soaking time. From disc-gel electrophoresis patterns of soybean milk protein and soybean curd protein, numbers of band were increased and major band thickened by expending the soaking time. Most of high molecular bands of soybean milk protein were transfered to soybean curd. Crude 7S proteins of soybean milk and soybean curd in dis-gel electrophoresis were appeared to be 4 and 5 bands respectively, and crude 11S proteins of soybean milk and soybean curd were appeared to be 9 and 8 bands respectively. Of soybean milk bands, most of 11S component transfered to soybean curd. Transmission electron photomicrographs revealed that the dimension of each protein body became larger and the numbers of spherosome around the protein bodies in unit area fewer by extending the soaking time of soybean.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.12-15
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• 2003

The effect of chlorella addition on quality and shelf-life of soybean curd was investigated. The yield of chlorella soybean curd was the highest with 1.0% (w/w) chlorella addition. Hardness, gumminess, and chewiness of chlorella soybean curd increased, whereas Hunters color values decreased in proportion to amount of chlorella added. No significant differences were observed between the sensory properties of chlorella and ordinary soybean curds. Microbial counts of soybean curd stored in sterilized distilled water as tofu-immersion solution increased, whereas pH decreased during storage at $15^{\circ}C$. After 5 days storage, microbial counts of the soybean curds containing 0.5 and 1.O% chlorella were lower than that of the ordinary soybean curd. These results imply that chlorella is a useful additive to suppress the proliferation of aerobic microorganism in soybean curd at the optimal concentration of chlorella around 1%.

• Food Science and Preservation
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• v.7 no.3
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• pp.249-255
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• 2000

Soybean curd has been known as one of the most favorite traditional Korean foods as well as being high in protein. Each concentration of added natural materials soybean curds was chosen as 4% of carrot, 10% of cucumber, 1.0% of spinach and 0.05% of green tea powder. The yield of soybean curd containing natural materials was similar to that of non-containing curd. According to add GDL as coagulant, the yield of soybean curd containing natural materials was the highest. The turbidity of added natural material soybean curds was the highest coagulated with $CaCl_2$, but soybean curd containing green tea had the highest turbidity in the coagulated with GDL. In the chromaticity and texture properties of the additive natural materials in yhe soybean curd, the variety of additives had no effect. In the composition of natural materials, the carotenoid and chlorophyll content of soybean curds were high with $MgCl_2$ and $CaCl_2$ but polyphenol was high use of $CaSo_4$ and GDL.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.363-368
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• 1990

As a work on the investigation of the processing aptitude of the Korean soybean cultivars, the soybean curd was made from 19 Korean soybean cultivars on a laboratory scale. The yield, proximate composition and rheological and organoleptic property of the resultant soygean curd were analyzed. The yields of soybean curd were ranged from 262.33% to 311.63%, being positively correlated with the soluble protein contents of the recommended soybean cultivars (r=0.9621). The recovery rate of protein in Baekun and Yeunha to the soybean curd was 72.94%, 70.62%, respectively. More than 80% of lipid in soybeans of Yeunha, Dankyung, Danyeob was transferred to the soybean curd. Lightness of the soybean curd made from Baekun, Kwanggyo, Saeal, Hill was higher than that of the others. The mechanical hardness of the soybean curd was strongly correlated with the final moisture content of the soybean curd (r =-0.8312), but not with the protein content of the soybean (r=0.1848). In the organoleptic test for color, texture, flavor and overall preference of the resultant soybean curd, the quality of Dankyung, Namcheon, S-138, Baekun was evaluated highly.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.355-358
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• 1994

The effect of concentration of coagulant and addition of phytic acid on physico-chemical properties of soybean curd was investigated. The results showed that the maximum protein yield in soybean curds was obtained with 0.029N Ca and the bound calcium per protein molecule significantly increased as the level of calcium increased. The highest precipitation of phytic acid occured at 0.029N Ca. When phytic acid was added to soybean milk during soybean curd preparation, the weight of soybean curd increased. The hardness of soybean curd was remarkably reduced by the increase of phytic acid level.

• The Korean Journal of Food And Nutrition
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• v.24 no.1
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• pp.12-16
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• 2011

This study was conducted to investigate the quality characteristics of soybean curd prepared with Opuntia ficus-indica fruit, freeze-dried Opuntia ficus-indica fruit powder, or heat-dried Opuntia ficus-indica fruit powder, without addition of a coagulant. The yield rates of the soybean curd were slightly decreased for the three curds containing Opuntia ficus-indica fruit; this was accompanied by a significant decrease in pH. Furthermore, the hardness and springiness of soybean curds coagulated with added freeze-dried Opuntia ficus-indica fruit powder or heat-dried Opuntia ficus-indica fruit powder were higher than the hardness and springiness of the coagulated controls. However, the cohesiveness and brittleness of two soybean curds were lower than for the controls, while the gumminess of the four soybean curds containing control fruit was the same. In terms of overall acceptability, the preferred soybean curd was the curd containing freeze-dried Opuntia ficus-indica fruit powder.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.135-143
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• 2008

The ratio between 11S Sand 7S globulins was greater in large seed size varieties (LSSVs) of soybean than in small seed size varieties (SSSVs) or medium seed size varieties (MSSVs) but did not differ between MSSVs and SSSVs. The cysteine and methionine contents of 11S globulins were greater than those of total seed proteins and 7S globulins. The acidic monoamino monocarboxylic amino acids were the most abundant class of amino acid in soybean seed (27.2%) and soybean curd protein (29.3%). Isolated 7S and 11S fractions were analyzed by HPLC. Of the 12 peaks detected, 4 constituted 64.1% of the proteins of the SSSVs, 65.6% of the proteins of the MSSVs, and 70.5% of the proteins of the LSSVs. The 11S/7S globulin ratio was related to the yield and hardness of soybean curd. The MSSVs had the greatest yield of soybean curd, but the soybean curd hardness of the MSSVs was greater than that of the SSSVs. These results show that the 11S/7S ratio and color of soybean seeds can be used to predict the yield, hardness, and color of soybean curd.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.437-439
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• 2005

Freshness of stored soybean curd as sensitivity ($R_{gas}/R_{air}$) was evaluated at 48-50 hr intervals using electronic nose at regular sequential square-wave temperatures between $4\;-\;10^{\circ}C$. Obtained kinetic data from apparent first principal component score $(PC1)_{app}$ and storage time were used for prediction of freshness. Percentage difference between predicted and actual values of stored soybean curd was less than 8.9% under fluctuating temperature condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.632-636
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• 1996

Soybean and residue contained 59.0% dietary fiber and makkolli residue contained 26.0% dietary fiber. The breads made from flour consisting of 90% wheat flour and 10% fiber materials were compared with that made with 100% wheat flour in terms of baking performance and consumer acceptance. Replacement of 10% wheat flour by soybean curd residue or makkolli residue increased water absorption and loaf weigh, but reduced loaf volume. Sensory panels could not accept favorably the bread made with the soybean curd residue or makkolli residue in flour replacement at 10% level. The protein content was increased from 13.5% to 15.4% in bread containing 10% soybean curd residue and to 16.4% in bread containing makkolli residue. The dietray fiber contents of the bread with soybean curd residue and the bread with makkolli residue were three-fold and two-fold higher than the bread with flour.

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.111-121
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• 2012

The purpose of this study was to investigate the quality characteristics of Garaedduk with regard to the amount of added whole soybean curd (Chun-Tofu). Whole soybean curd was added in amounts of 0, 3, 6 and 9%. Whole soybean curd Topokki dduk was stored at room temperature for 48 hours. The moisture contents had no significant difference for increases in the amount of whole soybean curd. The L value and b values of Garaedduk increased significantly with increases in the amount of whole soybean curd. Texture characteristics of Garaedduk measured with a texture analyzer revealed that hardness and cohesiveness decreased significantly for different amounts of whole soybean curd, and hardness increased significantly and cohesiveness and chewiness decreased with increase of storage time. As for sensory characteristics, samples with 9% added whole soybean curd rated higher in overall acceptability compared with other samples. In regard to cooking properties, water absorption increased and solid contents decreased with increases in the amount of whole soybean curd. Therefore, Garaedduk containing 9% whole soybean curd was most preferable.