• 한국식품영양학회지
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• 제24권3호
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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.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.961-966
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• 2011

본 연구는 버섯성분을 함유한 두부의 면역조절물질로의 가치를 평가하고자 수행하였다. 표고버섯(Letino edodes)과 민자주방망이버섯(Lepista nuda)의 자실체와 균사체를 두유에 첨가하고 응고제로 $CaSO_4{\cdot}2H_2O$ 또는 젖산발효추출물을 사용하여 두부를 만들었다. 두부와 버섯성분이 함유된 두부의 영양성분을 분석하였다. Sandwich ELISA를 이용하여 비장세포 배양액에서의 IFN-${\gamma}$와 IL-4및 TNF-${\alpha}$농도를 분석하였으며, 또한 혈장과 비장세포 배양액에서 IgG1, IgG2a 및 IgE등의 농도를 측정하였다. 조단백과 조지질은 버섯성분을 함유한 두부에서 감소되었으나, 인은 유의적으로 증가하였다. IFN-${\gamma}$는 자실체나 두부를 투여한 생쥐에서 유의적으로 감소하였으며, IL-4는 표고버섯 자실체가 함유된 두부를 투여한 생쥐에서 크게 감소하였다. TNF-${\alpha}$는 표고버섯 성분을 함유한 두부를 투여한 생쥐에서 유의적으로 증가하였다. 혈장의 IgG1은 거의 모든 실험군에서 증가되었으나, IgG2a는 대조군에 비해 큰 변화가 없었다. 비장임파구 배양액에서 측정한 IgG1 와 IgG2a의 농도는 자실체나 균사체를 첨가한 두부의 대부분의 그룹들에서 현저하게 높게 나타났다. IgE의 혈장농도는 두부나 표고버섯을 투여한 생쥐에서 크게 증가하였으나 버섯 성분을 첨가한 두부 투여 생쥐그룹에서는 그 생성이 억제되었다. 이러한 결과들은 버섯 성분을 함유한 두부들이 면역활성에 영향을 준다는 것을 나타내며, 면역활성의 관점에서 두부와 표고버섯의 혼합물은 개발가치가 있는 것으로 사료된다.

• 한국식생활문화학회지
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• 제21권6호
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• pp.644-652
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• 2006

두부는 식물성 단백질 자원의 식품으로 세계적으로 잘 알려져 있으며 우리나라의 전통식품이다. 최근 두부가 건강식품으로 인식되면서 품질 고급화를 위한 방안으로 화학 첨가물이 아닌 천연응고제로서 석류즙을 사용하여 두부를 제조하여 기계적 및 관능적 특성의 품질특성을 조사하고 저장성을 살펴보았다. 두부의 수율을 대조군이 485g/500ml이었으나 석류즙 첨가 두부군에서는 석류즙 3%(49.3g/500mL)가 가장 높고 석류즙 2%, 4% 순이었다. 두부여액의 탁도는 석류즙 첨가량이 많아질수록 높에 나타났으며 여액의 pH는 석류즙 첨가 두부가 대조군보다 낮게 나타났다. 두부의 색도에서 L(lightness)값은 대조군이 가장 높았으며 탁한 붉은 색의 석류즙 두부는 첨가량이 증가될수록 감소하였다. a(redness)값은 석류즙 첨가량이 증가될수록 커졌으며 b(yellowness)값은 대조군이 석류즙 첨가 두부군보다 높았다. 두부의 texture에서 경도(hardness)는 석류즙 첨가 두부가 더 단단하였고 응집성(cohesiveness)은 석류즙 4%, 5% 첨가군이 대조군보다 높고, 석류즙 1%, 2%, 3% 첨가군보다 낮았다. 탄력성(springness)은 P4>P5>P3>P2>P1순이며 검성은 석류즙 3%첨가군이 GDL두부와 유사한 특성을 보였으며(p<.001), 부지짐성(brittleness)은 석류즙을 많이 첨가할수록 높아지는 경향이 있었다. 두부를 $0^{\circ}C^$에 저장하는 동안 pH는 대조군은 증가하며 석류즙 첨가 두부는 감소하는 경향을 보였으며 산도에서 대조군은 석류즙 첨가 두부와 같이 증가하였으며 두부의 저장성에서 대조군은 12일 지나면서 107 CFU/g을 넘어 부패가 진행되었으나 석류즙첨가 두부는 세균의 증식속도가 감소되어 전 기간동안 대조군에 비해 저장성 연장을 볼 수 있었다. 두부의 미세구조에서 석류즙 2%, 3% 첨가 두부가 대조군과 균일하게 구조를 나타냈으며 석류즙 첨가량이 증가할수록 입자가 크고 불규칙하며 거칠었다. 두부의 관능특성에서는 외관이 기호도는 대조군이 가장 높았으나 석류즙 첨가 두부군에서는 석류즙 2% 첨가 두부가 외관(appearance), 향미(flavor), 맛(taste), 질감(testure)에서 가장 높았다.

• 한국식품조리과학회지
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• 제23권4호통권100호
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• pp.502-510
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• 2007

This study investigated the utilization of turmeric (Curcuma aromatica Salab.) for tofu manufacture and its effects on the quality characteristics and shelf-life. Various concentration (0.000%, 0.005%, 0.010%, and 0.015%) of turmeric were used to evaluate the shelf-life during tofu storage for 12 days at $10^{\circ}C$. The pH decreased with an increasing storage period, but the 0.010% and 0.015% tofu showed lower pH value than the 0.000% tofu, the acidity decreased with an increasing storage period. The water content of the turmeric tofu decreased with an increasing storage period. The turbidity gradually increased until 6 days of storage, and then rapidly increased at 12 days of storage. The microbial count of the 0.015% tofu was lowest during the storage period. In measuring the turmeric tofu color, the L- and a--values decreased during the storage period, while the b--value increased. In the texture analysis, hardness, gumminess, and brittleness of the turmeric tofu decreased 12 days of storage. Cohesiveness and springiness increased with an increasing storage period. In the sensory evaluation, Smoothness, after taste, and overall taste were highest for the 0.010% tofu. For the overall acceptability, the 0.010% tofu (with 0.45% mixed coagulant) attained the highest score.

• 동아시아식생활학회지
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• 제20권5호
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• pp.769-775
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• 2010

Quality characteristics and antioxidant activity of spirulina with added tofu were investigated in the presence of different coagulants ($CaSO_4$, $MgCl_2$, Glucono delta lactone (GDL), vinegar). The yield of the spirulina tofu was the highest when coagulated with GDL. The pH of spirulina tofu with $MgCl_2$ was the highest compared to those of other coagulants. The tumidity of spirulina tofu was the highest with $MgCl_2$. In the color analysis of spirulina tofu, the L (lightness) value was the highest with $CaSO_4$, whereas a (redness) value was the highest with $MgCl_2$. C-phycocyanin contents were the highest with the $CaSO_4$. Phycoerythrin of spirulina tofu for vinegar was 0.194 mg/mL, and GDL content was 0.214 mg/mL. Additionally, the antioxidant activity of spirulina tofu was the highest with $MgCl_2$ $IC_{50}$ values of the DPPH radical scavenging activity of spirulina tofu with $MgCl_2$ was 89.2 mg/g, GDL 93.5 mg/mL, $CaSO_4$ 116.7 mg/mL, and vinegar 118.0 mg/mL. The texture analyses (TPA) results showed that hardness was in the order of vinegar>$MgCl_2$>GDL>$CaSO_4$. For the overall acceptability of the preference test, the spirulina tofu that was made using $MgCl_2$ coagulant had the highest score. Based on these results, it is suggested that $MgCl_2$ is the proper coagulant for the preparation of spirulina with added 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.

• 한국식품조리과학회지
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• 제26권6호
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• pp.887-893
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• 2010

In this study, the quality characteristics of tofu prepared with added spirulina(0, 0.25, 0.5, 0.75, and 1%). As the concentration of spirulina increased, tofu yield decreased and the pH and turbidity increased. The Hunter L(lightness) and a(redness) values of tofu decreased as the amount of spirulina increased. Phycocyanin(C-phycocyanin, allophycocyanin and phycoerythrin) contents increased according to the spirulina amount. Moreover the antioxidant activity of tofu increased as the concentration of spirulina increased($IC_{50}$ values for control was 150.7 mg/g; 1% spirulina, 82.5 mg/g). Textural properties(TPA) for hardness, gumminess, and chewiness were higher in spirulina with added tofu, compared to those of control. Regarding the overall acceptability of sensory properties, spirulina with 0.5% added tofu had the highest scores among all treatments. From these results, it was suggested that the optimal amount of added spirulina was 0.5% for the preparation of high quality tofu.

• Applied Biological Chemistry
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• 제28권2호
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• pp.56-61
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• 1985

전기전도도법과 화학적 분석방법을 병행하여 두부의 제조공정중 Ca염의 수지를 분석하였다. 전기전도도법에 의한 Ca염의 수지분석(收支分析)이 $CaSO_4$를 응고제로 사용한 경우에는 불가능하였으나, $CaCl_2$를 응고제로 사용한 경우에는 화학적 방법에 의해 구한 것과 잘 일치하였다. 두유 및 두부의 제조공정중 대두에서 두유로 이동되는 고형분량과 Ca량은 각각 66%, 63%였고, 대두에서 두부로 이행되는 고형분은 47.8%였다. $CaCl_2$를 응고제로 사용한 경우 두부중 Ca 농도$(Y_{Tofu},\;mg{\cdot}Ca/g{\cdot}Tofu,\;wet\;basis)$ 및 순물중 Ca농도$(Y_{drained\;soln},\;mg{\cdot}Ca/ml{\cdot}drained\;soln)$는 두유중 첨가되는 $CaCl_2$의 량$(C,\;mg{\cdot}CaCl_2/ml{\cdot}soy\;milk)$에 비례해서 증가하였고, $81{\pm}0.5%$의 수분을 포함한 두부에 대하여 r=0.9898에서의 관계를 $Y_{Tofu}=0.3369C+1.2689$ 얻었고, 순물에 대해서는 r=0.9991에서 $Y_{drained\;soln}= 0.2899C+0.0399$의 관계를 보였다. $CaCl_2$를 응고제로 사용할 경우 원료대두를 제외한 모든 공정에서 전기전도도법에 의해 Ca 농도를 측정할 수 있음이 밝혀졌다.

• 한국식품영양학회지
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• 제33권5호
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• pp.576-583
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• 2020

The purpose of this study was to compare the quality characteristics of silken tofu products from the commercial market in Korea. Seven types of commercial silken tofu were sampled and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity, moisture contents (total solid contents), crude protein and fat contents were evaluated. The TPA results suggest that the texture of silken tofu was very different from one another according to the type of and the amount of coagulant. The commercial silken tofu showed a range of pH 5.53~6.48, total acidity of 0.12~0.32%, soluble solid contents of 2.62~5.07 °Brix, salinity of 2.28~4.30%, and moisture contents of 87.10~92.24%, respectively. In terms of the coagulant of tofu, besides the GDL (glucono-δ- lactone), other coagulants such as MgCl₂ for making 'silken tofu' in the Korean tofu market. The quality characteristics differed depending on the constituents of sample and the coagulants of tofu used. These results are expected to be useful in identifying new trends in the domestic silken tofu industry.

• 한국식생활문화학회지
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• 제33권3호
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• pp.217-228
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• 2018

This study aimed to develop unique, local "food tourism" products by finding specialized items that combine tourist attractions, such as folklore or hot springs. Traditional ingredients were analyzed with ancient texts for the methods of research. A brand image was made possible utilizing hot spring lore and other regional stories. The tofu products were produced using local specialty beans. Products, such as tofu residue cake and willow bean tea, were made with the tofu residue. After the products were completed, the sensory test began at the local tourist attraction. Asan City's food tourism product willow tofu was made with beans that were given as compensation for building the Onyang temporary palace according to the Annals of the Joseon Dynasty and the willow tree that appears in Sunshin Lee's anecdotes. After the preference test between normal tofu and willow-extract tofu was conducted to measure the product potential of willow tofu, among the sample extracts, 0.04% of the willow extract showed a significant preference. The hot spring tofu-residue cake was baked using tofu residue and vegetable olive oil to substitute for animal oil, such as butter, or margarine. After the sensory test targeting the adults was conducted, both products displayed significant product potential with average scores above 5.0. Willow tree bark, which has antioxidation and anti-inflammatory effects without a bitter taste or strong smell, was proven to bean appropriate ingredient for leached tea. The nutty flavor of leached tea was enhanced by roasted green kernel black beans and willow tree bark. The sensory test showed that the leached tea and tofu received a high preference rating on both color and flavor.