• 동아시아식생활학회지
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• 제22권3호
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• pp.386-391
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• 2012

The principal objective of this study was to evaluate the quality characteristics of black garlic milk tofu prepared with five different levels (0%, 0.5%, 1%, 1.5%, and 2.0%) of black garlic concentrate (BG0~BG4). We conducted the pH, total phenol and flavonoids, Hunter's color values, mechanical characteristics, and a sensory evaluation analysis of black garlic milk tofu. The total phenol and flavonoid content of black garlic concentrate were 1.67mg/100 g and 1.07 mg/100 g. The more black garlic concentrate increased, the more lightness (L) decreased, but redness(a) and yellowness (b) increased. The hardness, gumminess, and chewiness scores significantly increased (p<0.05) in all black garlic milk tofu samples. In color, taste, flavor, texture, and overall quality, the score of milk tofu with 1.0% black garlic concentrate (BG2) increased the most.

• 동아시아식생활학회지
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• 제19권2호
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• pp.231-237
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• 2009

The principal objective of this study was to determine the quality characteristics of tofu prepared with the addition of skate (Raja kenojei) powder. The moisture, crude ash, carbohydrate, crude protein, and crude lipid contents of the used skate powder were 5.34%, 14.15%, 1.90%, 76.60%, and 2.08%, respectivly. The yield rate of the tofu did not differ significantly with the level of added skate powder; however, significant reductions in pH and a significant increase in acidity were observed. The L and b values of the tofu decreased with increases in the amount of added skate powder in the formulation, whereas the a values increased directly with the amount of added skate powder. Furthermore, hardness was increased significantly as the level of skate powder increased. In terms of overall acceptability, the preferred tofu samples were the control and the group to which, 1.0% skate powder was added.

• 동아시아식생활학회지
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• 제19권5호
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• pp.743-749
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• 2009

This study was conducted to investigate the quality characteristics of tofu prepared with the addition of shrimp powder. Moisture, crude ash, carbohydrate, crude protein, crude lipid of the used shrimp powder were 3.81%, 0.70%, 42.15%, 49.36%, and 3.98%, respectivly. The yield rate of the tofu did not differ significantly according to the level of added of shrimp powder, however there was a significant decrease in pH and a significant increase in acidity. The L and b values of the tofu were decreased as the amount of shrimp powder in the formulation increased, whereas the a values was increased. Furthermore, hardness was significantly increased as the level of shrimp powder increased. In terms of overall acceptability, the preferred tofu samples were the control and that containing 2.0% shrimp powder addition group.

• 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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• 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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• 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.

• 한국식생활문화학회지
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• 제28권5호
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• pp.495-501
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• 2013

The quality characteristics of tofu added Ligularia fischeri powder (LFP) were investigated. The proximate composition of LFP used was as follows: moisture, 7.7%; crude protein, 12.0%; crude lipid, 5.9%; crude ash, 14.1%; and carbohydrate, 60.3%. The yield of tofu added LFP increased with the addition of LFP. However, there was a significant decrease in pH (from $6.03{\pm}0.11$ in the control to $5.78{\pm}0.11$ when 0.4% LFP was added) and a significant increase (from $2.60{\pm}0.01$ in the control to $2.85{\pm}0.10$ when 0.4% LFP was added) in total acidity. In addition, the L, a, and b values of tofu decreased with the increasing addition of LFP. In terms of textural properties, the hardness, cohesiveness, and brittleness increased, whereas springiness decreased, with the increasing addition of LFP. In the sensory evaluation, the overall preference for tofu added 0.3% LFP was the highest. According to the results, the addition of LFP positively affects the overall sensory evaluation of tofu, and 0.3% is the optimal level for addition.

• 한국수산과학회지
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• 제41권2호
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• pp.77-83
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• 2008

This study investigated the quality of tofu prepared by treating soybean milk with deep seawater as a coagulant. The quality and shelf-life of the tofu prepared using the deep seawater coagulant were determined and compared to those using $CaSO_4$, surface seawater, and intermediate seawater coagulant. The tofu made with the deep seawater coagulant was firmest. In addition, the deep seawater tofu product had more, smaller particles in the microscopic view, compared to the tofu made from surface and intermediate seawater coagulants. The deep seawater tofu product had the lowest viable cell counts and turbidity. In addition, the deep seawater tofu product had a longer extended shelf-life. From these results, deep seawater appears to improve the texture, taste, and shelf-life of tofu when used as a coagulant.

• 한국식생활문화학회지
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• 제27권5호
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• pp.521-527
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• 2012

This study was conducted to examine the quality characteristics of tofu prepared with Loquat (Eriobotrya japonica Lindl.) leaf powder (LLP). Moisture, crude ash, carbohydrate, crude protein, and crude lipid contents of Loquat leaf powder were 10.25, 6.72, 69.54, 8.23, and 5.26%, respectively. The yield rates, turbidity, and total acidity of tofu increased according to the quantity of added LLP, whereas pH level decreased. The L- and a-values of samples decreased as the amount of LLP increased, whereas b-value increased. With regard to textural characteristics, LLP addition increased hardness, chewiness, and brittleness, as well as reduced springiness and cohesiveness. In terms of overall acceptability, the most preferred tofu samples were the control and 0.3% LLP addition groups.