• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.529-535
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• 1996

This study was performed to investigate some quality characteristics of 새려 prepared from soybean milk and various seaweed(Undaria pinnatifida, Laminaria japonica, Porpyra tenera, Enteromorpha sp., Codium sp.) pulps in the ration of 9:1(v:v) with 20% MgCl2. The yields of tofu containing Undaria pinnatifida, Laminaria japonica, or Enteromorpha sp. increased but porphyra tenera, Codium sp. decreased in comparison with tofu prepared from whole soybean milk. The protein content of tofu containing Undaria pinnatifida, Laminaria japonica, Porphyra tenera, or Codium sp. increased but Enteromprpha sp. decreased in comparison with the tofu prepared from whole soybean milk. The content of Ca in Undaria pinnatifida, Porphyra tenera added tofu was higher than that of the tofu prepared from whole soybean milk or other seaweeds added tofu. In sensory evaluation the texture, color, taste of tofu were favored with the addition of sea mustard(Undaria pinnatifida) pulp than that of the tofu prepared from whole soybean milk or tofu prepared other seaweed. Tofu prepared was possible with adding 0.5~1.5% sea mustard to soybean milk but the feasible added amount level was 1% of sea mustard. The yields, protein Ca, and K content of tofu were increased by the more adding amount of sea mustard tan tat of the tofu prepared from whole soybean milk. The hardness values of 1% sea mustard added tofu were decreased than that of the tofu prepared from whole soybean milk ; on the other hand, elasticity, cohensiveness, gumminess and brittleness of tofu with sea mustard increased. The L and a values of tofu were lower and b values were higher with the addition of 1% sea mustard. The content of histidine, tyrosine, leusine, and phenylalanine were decreased but the other amino acid were increased in tofu prepared from 1% sea mustard pulp added to soybean milk. The saturated fatty acid and monoene fatty acid content of tofu were increased and C18:2, C18:3(${\gamma}$), C18:3, C20:5 of polyene fatty acid were slightly decreased in tofu prepared from 1% sea mustard pulp added to soybean milk.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.369-375
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• 1994

This study was carried out to investigate the effect of beany flavor elimination and the acceptability of tofu prepared with blanched soybean. The results were as follows: 1. The content and me total protein of soymilk prepared with blanched soybean were decreased comparing with those of soymilk prepared with raw soybean. But the yield of tofu was not changed by blanching the soybean. 2. The beany flavor(hexanal, 1-hexanol, and pentanoI) was decreased but the toasted nutty flavor(ethanol and propanol) were increased by blanching the soybean. 3. By heating of soymilk, most of volatile compounds was disappeared, but ethanol, hexanal and 1-hexanol were remained. The hexanal content of tofu prepared with raw soybean was eleven times higher than that of tofu prepared with blanched soybean. 4. The color of tofu prepared with blanched soybean was more yellower than that of control group. At the lower temperature of blending, the texture of tofu was more smooth and elastic. 5. The tofu prepared with blanched soybean was more tasteful.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.2
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• pp.69-74
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• 1994

In order to improve the shelf-life of Tofu, the elimination of contaminated bacteria by ozone treatment was examined. Tofu prepared from ozone treated-soybean was investigated for microbial, physicochemical and sensory changes during storage at 20$^{\circ}C$ and 30$^{\circ}C$. As a result of treatment in ozonic water by 2~4ppm/sec for 3 hours, 90~98% of the total bacteria in material soybean for Tofu was eliminated. At 20$^{\circ}C$, control Tofu prepared from ozone treated-soybean was found to be spoiled after 72 hous. Titratable acidity and sensory changes of Tofu was increased as spoilage of Tofu was progressed, but pH was decreased at the first day of storage, and after that it was increased. At 30$^{\circ}C$, there was no remarkable difference between Tofu of control and Tofu prepared from ozone treated-soybean.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.451-457
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• 2011

The purpose of this study was to evaluate the effects of soybean varieties on the physicochemical and sensory characteristics tofu. Five varieties of soybeans(Daewon, Jinpoung, Hwanggum, Jinmi, and Manni) were selected for these experiments. Proximate composition and total phenolic acids in the soybeans, and the moisture, turbidity, lightness, yield rate, texture characteristics, and sensory characteristics of the tofu were measured. The Hwanggum soybeans had the highest levels of crude lipid and crude ash. There was a significant difference in the moisture and yield rate of the tofu(p<0.05). The crude protein and crude lipid contents of the soybeans affected the hardness and springiness of the tofu. In sensory evaluations, significant differences(p<0.05) were shown in taste, texture, and overall acceptability depending on the tofu by soybean variety. Therefore, one should consider soybean varieties when manufacturing tofu.

• Food Science and Preservation
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• v.23 no.6
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• pp.832-838
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• 2016

The purpose of this study was to investigate the effect of a fresh chlorella powder on yield, quality and self-life of organic soybean tofu. After added with a fresh chlorella powder, yields, physical properties, color, shelf-life and sensory properties of the organic soybean tofu added with chlorella powder was compared to the properties of soybean tofu. The yield of soybean tofu increased with the addition of more than 1% chlorella powder. Hardness of the organic soybean tofu with chlorella significantly increased compared to that of the soybean tofu. However, Hunter's color values of L, a, and b decreased by increases in the chlorella powder concentration. Total microbial population of the soybean tofu was higher than that of the organic soybean tofu with chlorella. However, pH of chlorella tofu decreased during storage period at $4^{\circ}C$. After 7 days storage at $4^{\circ}C$, the total microbial population decreased significantly with the addition of 2% chlorella powder. The L and a value of chlorella tofu was increased. On the other hand, the b value of chlorella tofu was decreased during storage. The results revealed that a fresh chlorella powder was a useful material to improve yield, quality and storage condition of the organic soybean tofu.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.5
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• pp.441-446
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• 2017

Among the many foods, it is hard to find perfect food with nutrition and functionality like beans. Korean food culture is the main ingredient of korean culture, kochujang, soybean paste, and soy sauce, and processed soybean tofu is the main ingredient. Soybean meets high quality protein and fat, and it has excellent results in prevention and treatment of all kinds of diseases. Soybean food is becoming a new generation health food. In countries where animal protein intake is low, soybean is used as a protein source instead of animal protein. Tofu, a processed food, is a complete food with high digestibility. In order to publicize the superiority of soybean nutritional value, Tofu processing and powder were investigated by observing the size, shape and characteristics of bean powder using domestic soybeans and imported soybean, and the variation of the amount of coagulant.

• Journal of the Korean Society of Food Culture
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• v.22 no.6
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• pp.696-704
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• 2007

To investigate of the perception and using behavior by age of tofu, 46.3% of male and 53.7% of female about 700 adults in Daegu and kyungbuk area were surveyed. 96.4% of the participants usually preferred the tofu owing to health and 68.4% of them had purchased tofu made of domestic soybean. In addition, the responses to 7 questions about the tofu were also measured on 5 point Likert scale. The item "Tofu is healthy food" was totally received the high point but "Tofu prevents osteoporosis" earned the lowest. Most participants relatively knew and had eaten common tofu, soft bean curd, uncurdled bean curd, fried bean curd against functional tofu such as tofu added with omija, surimi, spinach, etc. But they intended to eat functional tofu such as tofu added with green tea, black sesame, spinach, omija. Furthermore, 60.7% replied "increasing" prospects for the tofu consumption. 40.0% of adults said the plan should be "Make of good quality domestic soybean" for the purpose of better improvement to consume.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.455-459
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• 2001

Tofu (soybean curd) was made with whole soybean flour (WSF, 420 mesh) by various processing conditions of water addition ratio, heating time, coagulation temperature, molding pressure and 0.3% of mixed coagulant (CaSO₄:GDL=50:50(w/w)). Yield content of WSF-tofu was the highest in processing condition of 85℃ coagulation temperature, 10 times water addition, 5min. heating time and 25.00 g/㎠ molding pressure. As the increase of the water addition ratio from 8 to 14 times (water:WSF, v/w), Hunter's L and a values were increased. Raising of heating time (100℃, 1, 5, 10 and 15 min), a and b value were increased. Textural properties of WSF-tofu were significantly affected by coagulation temperature (75, 80, 85 and 90℃). Hardness was increased, but adhesiveness and cohesiveness were decreased. heating time was influenced on harness of WSF-tofu, but water addition ratio was not affected on hardness of WSF-tofu. Increasing of molding pressure (16.83, 25.00, 33.22 and 41.67 g/㎠, 1 hr) was resulted from a increased hardness, gumminess and chewingss of tofu, but adhesiveness was addition ratio, 5 min heating time and 25.00 g/㎠ molding pressure recorded the highest score in sensory evaluation test.

• 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 Society of Food Culture
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• v.22 no.6
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• pp.713-720
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• 2007

To investigate of the recognition and using behavior on the Tofu, 46.3% of male and 53.7% of female adults in Daegu and Kyungbuk area were surveyed. The main results are as follows : 96.4% of the participants usually preferred the Tofu owing to health and about 68.4% of them had purchased Tofu made of domestic soybean. In addition, the responses to 7 questions about the Tofu were also measured on 5 point Likert scale. The item "Tofu is healthy food" and "Tofu is digestive food" were totally received the high point but "Tofu prevents osteoporosis" earned the lowest. Female had generally better knowledge of Tofu than the counterparts. Most participants relatively knew and had eaten common Tofu, soft bean curd, uncurdled bean curd, fried bean curd against functional Tofu such as Tofu added with omija, surimi, spinach, etc. But they intended to eat functional Tofu such as Tofu added with green tea, black sesame, spinach, omija. Furthermore, 60.7% replied "increasing" prospects for the Tofu consumption. 40.0% of adults said the plan should be "Make of good quality domestic soybean" for the purpose of better improvement to consume.