• 한국식품영양학회지
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• 제27권2호
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• pp.302-309
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• 2014

In this study, the characteristics of soybeans with different cultivation methods depending on their origins and the properties of tofu made from these soybeans were studied. The isoflavone content was higher in the general Korean soybeans compared to the organic American soybeans. There were no significant differences among the Chinese soybean samples, so the cultivar method was considered to have a greater effect on the isoflavone contents rather than the cultivation method. The protein contents were higher in the tofu made from the general Chinese soybeans and the organic Korean soybeans. Furthermore, the tofu made from the organic Chinese soybeans contained the least amount of proteins. Isoflavone contents were not significantly different among the samples. Texture profile analyses consisting of hardness, cohesiveness, adhesiveness, springiness, and gumminess were all shown to be higher in the organic tofu than in general tofu, with the exception of adhesiveness. In sensory evaluation, color and texture were significantly different according to the samples, and the differences were found to be affected more by the origin of soybeans rather than the cultivation methods. According to this study, the physicochemical properties of the soybeans and tofu seemed to be influenced by the cultivation region rather than the methods.

• 한국식품영양학회지
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• 제20권2호
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• pp.158-163
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• 2007

The compositions of tofus made with Baktae and Huktae were compared to those made with other respective types of soybeans. The lipid and protein contents of Baktae were 20.8% and 39.7%, while those of Huktae were 15.8% and 41.1%, respectively. In both soybean types, linoleic acid(18:2), oleic acid(18:1), and palmitic acid(16:0) accounted for more than 80% of the total fatty acids. The tofu made from Baktae was whiter than the tofu made from Huktae, as exhibited by a higher Hunter's L-value. The lipid content of the Baktae tofu(4.41%) was higher than that of the Huktae tofu(3.26%). The amino acid compositions of the Huktae and Baktae tofus were similar, with glutamic acid and aspartic acid being the most abundant amino acids in both tofus. However, the content of the limiting amino acid, methionine, increased 2.5-fold in the tofus as compared to the soybeans, on a per gram protein basis. Isoflavones were lost during tofu making as contents for the tofu were 20${\sim}$25% of those for the soybeans.

• 한국식품조리과학회지
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• 제20권1호
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• pp.17-25
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• 2004

This study was carried out to investigate the frequency of use, knowledge, purchasing, and degree of perception of processed soybean by residents in the Kwangwon area of Korea. The frequency of use of soybean curd was once per 4∼6 days(37.9％), once per 2∼3 days(31.9％), once per ten days(25.3％) and everyday(4.9％). The degrees of knowledge about soybean curd were a little(56.0％), interest(16.5％), much(14.8％) and no interest(12.7％). 73.9％ of respondents had no experience of preparation soybean curd. The frequency of places for the intake of soybean curd were home(83.5％), restaurant(8.8％), tofu restaurant(5.6％) and the others(2.1％). The frequency of places for purchasing of soybean curd were supermarket(59.5％), market(25.0％), the others(9.9％) and department store(5.6％). The degrees of perception of soybean curd types were soybean curd(100％), uncurdled soybean curd(93.7％), soft soybean curd(64.7％), bun soybean curd(15.7％) and seaweed soybean curd(5.2％). The experience on the use of processed soybean of the respondents was highest for soybean curd(98.6％), followed by bean sprouts, soybean paste, soy sauce, soybean oil, soy flour, residue of soybean curd, soy milk, in that order. The most frequent intake experiences of soybean processed products of the subjects were beanpaste pot stew(96.8％), followed by tofu pot stew, tofu and kimchi pot stew, uncurdled bean curd pot stew, bean mixed rice, grilled tofu, in that order.

• 한국식품저장유통학회지
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• 제12권6호
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• pp.516-521
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• 2005

[ $0.1\%$ ] chitosan 용액에 1시간동안 침지시킨 두부를 $10^{\circ}C,\;\20^{\circ}C\;and\;30^{\circ}C$에서 저장하면서 두부의 품질 변화를 측정하였다. $20^{\circ}C$의 경우 chitosan 처리구에서 저장 2일째까지 약 1 log cycle정도의 성장이 억제되었으나 3일 이후부터는 대조구와 chitosan 처리구간의 차이는 크지 않았다. $10^{\circ}C$의 경우 chitosan 처리구는 대조구에 비해 저장 전 기간동안 성장이 억제되었으며 $ $10^7\;CFU/mL에 도달하는 시점이 대조구에 비해 chitosan 처리구가 약 1일 정도 연장되는 경향을 나타내었다. pH는 $10^{\circ}C$ 저장에서는 대조구와 chitosan 처리구 각각 3일과 4일 이후부터 감소하는 경향을 나타내었다. $30^{\circ}C$와 $20^{\circ}C$에 저장한 경우 저장 2일 이후부터 hardness가 감소하였으며, chitosan 처리구는 저장온도와 관계없이 대조구에 비해 경도가 높게 나타났다. 두부의 색도는 저장기간이 경과할수록 L값은 낮아지고 a값과 b값은 증가하는 경향을 나타내었는데, chitosan처리구의 경우 대조구에 비해 L, a, b값의 변화율이 낮은 경향을 나타내었다.

• 한국식품영양학회지
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• 제31권1호
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• pp.62-69
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• 2018

Pumpkin (Cucurbita moschata Duch.) seed is rich in protein and sulfur-containing amino acids. Tofu is a protein gel made from soybean, which is rich in lysine but lacking in sulfur-containing amino acids. This study was conducted to investigate the use of pumpkin seeds in tofu manufacture and to determine its quality and texture characteristics. Soybean was substituted with pumpkin seed to obtain pumpkin seed tofu at the following ratios: 10%, 30%, 50%, and 70% (P10, P30, P50 and P70). Tofu manufactured only with soybean was used as a control (Con). The higher rate of pumpkin seed substitution significantly decreased the moisture content and yield rate (p<0.05). In contrast, pH value and turbidity were significantly increased with the increase in the amount of pumpkin seed (p<0.05). The L-value (81.74~79.04), a-value (-0.19~-3.89) and b-value (12.40~9.84) of samples significantly decreased with the amount of pumpkin seed (p<0.05). No significant difference in syneresis was found among the samples (p<0.05). The hardness tended to decrease with the increase in the amount of pumpkin seed. The microstructure analysis revealed that the pore size of pumpkin seed tofu was smaller than that of Con. These results suggest that the pumpkin seed protein is a useful ingredient in the manufacture of tofu. Increasing the pumpkin seed substitution levels improves the texture of tofu.

• 한국식품영양학회지
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• 제35권6호
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• pp.521-530
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• 2022

This study was conducted to compare the quality characteristics of commercial tofu products from the market in Korea. Seventeen types of commercial tofu samples were taken and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity and moisture (total solid contents), were analyzed. The hardness of tofu was negatively correlated with the moisture contents of tofu (r=-0.667^**). The commercial tofu showed pH 5.80~6.24, total acidity of 0.016~0.034%, soluble solids of 1.50~3.45°Brix, salinity of 1.20~2.30%, and moisture content of 79.91~87.57%, respectively. All 17 tofu samples sold in the Korean market were prepared using crude MgCl₂ and sea water as a coagulant. The quality characteristics vary depending on the constituent's of soybeans, and the ratio and amount of coagulants of tofu used. The origin of soybean seeds affected the yellowness of tofu; tofu made from imported soybean showed a higher b value than domestic soybean. These results are expected to be useful for understanding trends in the domestic tofu industry.

• 동아시아식생활학회지
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• 제16권6호
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• pp.707-716
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• 2006

To make tofu (soybean curd) with cuttlefish int the cuttlefish ink diluted 20-fold was added to soymilk in the ratio of 0%, 1%, 3%, 5%, 7% and 9% there is no respective comparison here respectively and the prepared cuttlefish inky tofu samples were stored for 15 days at $4^{\circ}C$. After storage, the tofu samples were tested for yield, pH, acidity, bacterial growth, sensory evaluations and physical properties. The yields of 7%(I7) and especially 9%(I9) cuttlefish ink tofu were higher than that of the control tofu(I0). The pH was decreased, but the acidity was increased with increasing storage period. The microorganism count of I9 was the lowest during the storage period. The turbidity gradually increased until 9 days of storage and rapidly increased at 12 days of storage. In the measurement of inky tofu color, the L and b values were decreased during the storage period. In the texture analysis, the hardness, gumminess and brittleness of inky tofu were increased until 12 days of storage but then decreased. Chewiness was decreased with increasing storage period. Springiness of Il and I3 was higher than that of I0. In sensory evaluation, color was increased with increasing cuttlefish inky concentration. Sleekness of I3 was the highest. Hardness and chewiness of inky Il and I3 were the highest. Springiness, cohesiveness and softness were the highest in I3. In overall acceptability, I3 gained the highest score.

• 한국식품영양과학회지
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• 제33권3호
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• pp.603-608
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• 2004

제주 전통두부의 산업 를 위한 최적 공정을 확립하고 해수를 대용할 수 있는 응고제를 사용하여 맛과 영양성 및 저장성이 향상된 고품질의 전통두부를 생산할 수 있었다. 즉 대두원료의 침지는 동절기 및 하절기에 각각 12∼16시간, 8∼10시간이 적합하였다. 가수량은 원료 대두량의 8배가 적합하였으며, 이 때의 두유농도는 8$^{\circ}$Brix였다. 두유는 10$0^{\circ}C$에서 2분 정도 가열하는 것이 단백질의 유리 thiol잔기의 노출을 최대화하였다. 연속 가열솥 대신 진공솥으로 대치한 결과 압력과 온도조절이 용이하여 수율이 21% 증가하였으며, 제품의 품질관리가 용이하였다. 마른두부의 응고제로는 6% 죽염액과 다시마침출액을 1 : 1의 비율로 혼합하여 1차 응고제를 만들고, 키토산 1 L에 CaCl$_2$8g과 MgCl$_2$ 2g의 비율로 혼합하여 응고제를 얻었다. 최종 마른 두부의 소비자의 기호도는 60%이상이 보통 이상으로 평가하였으며, 고소한 맛과 견고성이 우수하면서 전체적인 기호도가 시판두부에 비해서 유의적인 차이를 보이면서 우수하였다.

• 생명과학회지
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• 제27권11호
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• pp.1299-1307
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• 2017

LOX-1,2,3 결핍과 비소화성 당류인 raffinose와 stachyose 함량이 낮은 품종(LRS)인 진양콩, 하영콩 및 대복콩을 원료로 하여 제조한 두부의 품질특성을 태광콩 두부와 비교하였다. 태광콩과 하영콩의 백립중은 여타 시료에 비해 유의적으로 높았다. 조단백질 함량은 태광콩에 비해 진양콩 및 하영콩에서 유의적으로 많았다. 두부의 수율은 태광콩, 하영콩 및 대복콩으로 만든 두부가 비슷한 수준이었다. 두부의 경도는 태광콩 및 대복콩으로 만든 두부가 가장 낮았으며, 하영콩으로 만든 두부에서 유의적으로 높았다. 콩 및 두부의 이소플라본 함량은 대조구에 비해 LRS 콩은 약 1.4~1.6배, 두부는 약 1.8~3.4배 높은 함량이었다. 콩의 총 페놀 함량은 대조구에 비해 하영콩 및 대복콩에서 유의적으로 높았다. 두부의 총 페놀 및 플라보노이드 함량은 대조구에 비해 하영콩 및 대복콩으로 만든 두부에서 유의적으로 높았다. 콩의 항산화 활성은 태광콩이 LRS 콩에 비해 높은 활성이었으나, 두부에서는 하영콩 및 대복콩으모 만든 두부가 대조구에 비해 유의적으로 높았다. 따라서 LRS 콩은 두부 제조에 적합하나 특히 하영콩이 콩의 단백질, 이소플라본 함량 및 두부의 항산화 활성 측면에서 가장 우수한 것으로 판단된다.

• Applied Biological Chemistry
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• 제26권4호
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• pp.205-210
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• 1983

유청(乳淸)과 대두(大豆) 단백질(蛋白質) 공동침전(共同沈澱)에 의해 제조된 아미노산 강화두부(强化豆腐)의 특성(特性)을 조사하기 위하여 유청(乳淸)또는 유청분말(乳淸粉末)과 두유(豆乳)를 혼합하여 두부를 제조하고 이때 얻어지는 강화 두부의 일반조성, 아미노산 조성을 분석하고 물리적 특성도 비교하였다. 강화 두부는 외관이나 특성(特性)에서 재래식 두부와 큰 차이가 없었다. 전고형분 함량은 재래식 두부가 약 19%, 강화 두부가 17.3$\sim$18.1%이고 단백질 함량은 재래식 두부가 13.1% 강화 두부의 경우 10.9$\sim$11.4%로서 모두 재래식 두부가 높았다. 유청의 조지방(粗脂肪) 함량(含量)이 낮으므로 유청의 혼합비율이 높아질수록 두부 중 지방함량은 낮아졌으며 유청(乳淸) 두유(豆乳) 혼합물 중의 유당은 5$\sim$15%가 강화 두부에 이행되었다. 유청과 두유를 3:1로 혼합하여 제조한 경화 두부의 함유황(含硫黃) 아미노산 함량은 3.80g/100g 단백질로서 재래식 두부의 2.54g에 비해 약 50% 강화효과를 보였다.