• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.414-420
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• 2010

To develop tofu enhanced nutrition, storage stability and bioactivity, the soft tofu supplemented with red ginseng extract was prepared. Then, quality characteristics including storage stability, physical and chemical property, antioxidative activity, and sensory evaluation were measured. The pH and acidity of control tofu without red ginseng extract were not different from those of tofu supplemented with red ginseng extract during storage. The aerobic bacteria in the control tofu were detected from 10 days of storage whereas the number of total aerobic bacteria was reduced or not detected in the tofu added red ginseng extract during storage. The lightness and redness of the tofu supplemented with red ginseng extract were lower than those of control, but yellowness was higher. The addition of red ginseng extract did not also affect the texture of tofu, and increased lipid peroxidation inhibition and DPPH radical scavenging activity. Although the soft tofu manufactured with red ginseng extract showed a lower sensory preference in supplementation over 0.20% due to color, there was not much difference found until 0.18% red ginseng extract addition.

• Food Science and Preservation
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• v.10 no.1
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• pp.41-46
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• 2003

To prove the extension of shelflife of soybean curd(Tofu) steeped in the diluted solution of botanical antimicrobial agent and stored at 20$^{\circ}C$, such chemical ＆ microbial properties as the contents of moisture, crude protein and crude fat, colony count and surface color of Tofu were investigated in comparison with the control. Tofu treated with botanical antimicrobial agents showed higher contents of moisture, crude protein and crude fat compared to those of the control Tofu through all the storage period. After 7 days of the storage period, cell count of coliform bacteria reach 75 x 103CFU/m1 in the control Tofu, whereas 13∼39 CFU/ml in Tofu treated with botanical antimicrobial agent Treatment of Tofu with botanical antimicrobial agent seemed to be a potential method to prolong the shelflife of processed Tofu.

• Journal of Dairy Science and Biotechnology
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• v.38 no.4
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• pp.222-229
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• 2020

This study was conducted to develop a novel cheese tofu hybrid product by increasing the calcium content of cheese, an animal protein source, and tofu, a vegetable protein source. Both pH and moisture were lower in the cheese tofu hybrid than those values in the control group (6.03% and 72%, respectively). Protein and fat were slightly higher than in the control (15.43% and 9.91%, respectively). Total bacteria count increased at the end of the product's shelf life, but did not affect its texture. The cheese tofu hybrid displayed stronger a) red, and b) yellow coloration than the control, and its lightness (L) was lower than that of the control. The cheese tofu hybrid possessed high hardness, and displayed high values for gumminess and brittleness. Sensory evaluation by a specialized agency examined consumer preferences, purchase intentions, strengths, and weaknesses of the developed product line. A panel of 30 female volunteers in their 20s and 40s recorded an overall preference for cheese tofu of 5.40 points, fairly good. Cheese tofu was found to be better than the control tofu, with appealing differences in appearance, color, nutty aroma, chewiness, and cheese flavor.

• Journal of Life Science
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• v.27 no.11
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• pp.1299-1307
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• 2017

The quality characteristics of three non-genetically modified (GM) LRS soybean cultivars free of LOX 1, 2 and 3, such as Jinyang, Hayoung and Daebok, were compared to the characteristics of Taekwang, a soybean with LOX 1, 2 and 3 and general contents of raffinose and stachyose. Taekwang was used as a control soybean. The weights of 100 for Taekwang and Hayoung soybeans were significantly higher than those of the other samples. The crude-protein contents of the Jinyang and Hayoung soybeans were significantly higher than the crude-protein content of the Taekwang soybeans. Similar tofu yields were observed in the Taekwang, Hayoung and Daebok soybeans. The highest tofu yield was observed in the Hayoung soybeans. The isoflavone contents of the soybeans and tofu were 1.4-1.6 times and 1.8-3.4 times higher than the contents of the control soybeans, respectively. The total phenol contents of the Hayoung and Daebok soybeans were significantly higher than the contents of the control soybeans. Additionally, the total phenol and flavonoid contents were significantly higher in the tofu made from the LRS cultivars than in the tofu made from the control cultivar. The antioxidant activities of the Taekwang soybeans were higher than the antioxidant activities of the LRS-cultivar soybeans. However, the antioxidant activities of tofu made from the LRS cultivars were significantly higher than the antioxidant activities of tofu made from the control cultivar. The results suggested that the soybeans of the LRS cultivars were suitable for tofu products. The Hayoung cultivar may be the most suitable due to its higher crude protein and isoflavone contents and its significant antioxidant activity.

• Food Science and Preservation
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• v.24 no.7
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• pp.942-948
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• 2017

To establish manufacturing technology of tofu shake added with red rice prepared with Monascus purpureus KCCM 60570, the quality characteristics of tofu shake added with M. purpureus KCCM 60570 were investigated. Also, we determined the optimal mixing ratios of raw materials including red rice for manufacturing tofu shake. Monacolin K and mold number of red rice were increased rapidly until $8^{th}$ day of incubation and then gradually increased during the 12 day manufacturing period. As the results, it was considered to be most suitable to prepare red rice for 8 days at $25^{\circ}C$, and inoculate 1% (w/w) M. purpureus KCCM 60570. Sensory evaluation of tofu shake added with red rice and tofu shake without red rice was not significantly different at p<0.05. In sensory evaluation, tofu shake added with 0.5% (w/w) red rice was higher in taste, texture, and overall acceptability than the other. Therefore, the optimal mixing ratio of red rice and tofu shake is 0.5% (w/w). These results suggest that the addition of red rice could improve the quality of tofu shake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.986-991
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• 2010

This study was conducted to investigate the changes of mineral, oxalate and phytate during tofu processing with Korean recommended soybean cultivars. Fourteen cultivars were selected by distribution of calcium, oxalate and phytate contents. Tofu was manufactured and analyzed for quality characteristics, mineral, oxalate and phytate contents. The yield and moisture contents of tofu ranged from 137.77% in Anpyeongkong to 201.91% of Geomjeongkong 4, and 74.42 (Bongeuikong)~80.01% (Hojangkong), respectively. The lightness (L-value), redness (a-value) and yellowness (b-value) ranged from 53.05 (Dawonkong) to 86.16 (Jipumkong 2), -2.04~5.85, and from 3.28 in Geomjeongkong 4 to 16.17 of Cheongjakong, respectively. The hardness of tofu with selected soybean cultivar ranged from 537.36 g (Dongpuktae) to 1696.05 g (Jinpumkong 2). The highest calcium content was 1.488 mg/g in Dawonkong, oxalate and phytate in tofu were high at 0.40 mg/g in Geomjeongkong 4 and 0.41 mg/g in Dawonkong, respectively. The transfer ratios of oxalate and phytate from soybean to tofu were ranged from 0.31~19.70 and 0.41~19.70%, respectively.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.329-333
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• 2011

Quality characteristics of tofu as affected by addition time (before or after coagulant) and the amount (0, 3, 6, and 9%) of astringent persimmon fruit (Diospyros kaki T. cv. Cheongdobansi) powder added were investigated. Yield and sensory acceptability were higher in tofu prepared by adding persimmon before than after adding the coagulant. The yield of tofu with added persimmon was higher than that of the control. The L value of the tofu decreased as the amount of added persimmon increased. Hardness, chewiness, and crispness of tofu made with 6% persimmon were higher than those of the others. DPPH radical scavenging activity tended to increase as persimmon concentration increased but no significant difference was observed between the 3% and 6% added persimmon treatments. A sensory evaluation showed no significant differences in aroma, beany, astringency, and texture. However, the 9% sample had the significantly lowest score for overall acceptability. Thus, astringent persimmon powder (3-6%, before coagulant addition) can be utilized as an additive during tofu processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.603-608
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• 2004

Traditional Jeju tofu with a hard texture was manufactured by traditional method with a compounded coagulant. The processing condition for industrial production was optimized by determining soaking of soybean, extraction and heat treatment of soymilk as well as concentration and composition of coagulant. Maximum yield of soymilk was obtained by grinding one part of soaked soybean with eight parts of water, and the soluble solid of soymilk was about 8$^{\circ}$Brix. The free thiol group in soymilk was maximally exposed by heating at 10$0^{\circ}C$ for 2 min. A vacuum cooker for heating soymilk was effective for the improvement of yield and texture properties of tofu. The hardness of traditional Jeju tofu was obtained by increasing pressing time and drying by a fan instead of soaking in cold water. Optimization of a traditional tofu production resulted in the increase of total yield and improvement of quality control. Texture of traditional Jeju tofu prepared in industrial production scale was analyzed by instrumental analysis and sensory evaluation. Traditional Jeju tofu showed higher score in the hardness, roasting taste and overall preference compared with a commercial tofu, showing significant difference in 5% significant level..

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.92-96
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• 1992

Several coagulants was investigated for their effects on shelf-life of packed Tofu. The titratable acidity, amino nitrogen content in Tofu and the optical density of Tofu suspension were increased as the spoilage developed during storage. The number of microorganisms was increased to 13 million cells per gram after 1 day of storage at $30^{\circ}C$ in the Tofu prepared with $MgSO_{4}\;and\;CaCl_{2}$. But, the Tofu prepared from acetic acid was found to be more stable for storage. The quality of Tofu was maintained up to 12 days or 18 days at $30^{\circ}C\;or\;15^{\circ}C$, respectively. These results suggested that acetic acid was desirable as a coagulant of packed Tofu to extend its shelf life.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.129-135
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• 2002

The effects of adding green tea powder on the quality and storage characteristics of tofu were studied. As the addition of green tea powder increased, the moisture content of tofu was decreased but those of crude protein and the crude ash were increased. The addition of green tea powder increased the production of whey and consequently decreased the yield of tofu. At the beginning of storage, the pH of the tofu with green tea powder was increased, but decreased rapidly at the eighth day of storage. The pH of tofu-soaking solution was decreased during the storage period. The L and b values showed no significant changes but a value was increased during storage. Textural characteristics of tofu added with green tea powder also did not show significant changes during storage. Although the total plate counts and absorbances of soaking solution of tofu were increased during storage, the samples with 1.0% green tea powder had the lowest TPC (3.0$\times$10$\^$6/ CFU/ml) and the lowest absorbance (0.175) at the eighth day of storage.