• Culinary science and hospitality research
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• v.18 no.5
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• pp.293-304
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• 2012

This study was conducted to improve the sensory acceptability of modified Kochujang added with Tofu powder(25%, 50%, 75%, 100%) instead of Meju powder. These Kochujang samples were fermented for 45 days and examined in physicochemical properties and sensory characteristics. The result was as follows. Moisture content of the control was higher than that of the other Tofu powder Kochujang samples, which lasted for 30 days of storage. Moisture contents of all samples were increased by storage time. The pH of Kochujang added with Tofu powder was higher than that of the control. In general, pH values were decreased by storage time. Acidity decreased with Tofu powder increased while it generally increased with more storage time. In the lightness(L value), redness(a value) and yellowness(b value), control Kochujang was the lowest. There were no significant differences in the reducing sugar contents except 45 days. In sensory evaluation, color of Kochujang was evaluated light and off-flavor got weaker with Tofu powder increased. In the sensory attributes of odor, taste, overall acceptability, Tofu powder added Kochujang had high scores than the control, and especially 100% TP Kochujang had the best score.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.4
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• pp.547-553
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• 2007

The physicochemical and functional properties of tofu prepared with kanghwang(Curcuma aromatica Salab.) were investigated, in order to study the effects of six different commercial coagulants. The coagulant concentrations were determined as 0.3% GDL, 0.3% $MgCl_2$, 1.0% $CaCl_2$, 1.5% $CaSO_4$, 0.45% mixed coagulant, and 1.5% Milky-Mg by pre-experiments. Also, the optimum concentration for the added kanghwang(Curcuma aromatica Salab.) was chosen as 0.01%. The yields of the kanghwang tofu prepared with Milky-Mg, mixed, and GDL coagulants were higher than those prepared with $MgCl_2$, $CaCl_2$, and $CaSO_4$. The pH of the kanghwang tofu prepared with the $MgCl_2$ coagulant was higher than when made with the other coagulants. The turbidity of the kanghwang tofu was highest when it was coagulated with GDL, and moisture content was highest or the of kanghwang tofu coagulated with $CaCl_2$. In the color analysis of the kanghwang tofu, the $L^{***}$ value was highest with the Milky-Mg coagulant, while the $a^{***}$ value was highest and the b value lowest with the GDL coagulant. For the textural properties, the hardness results were in the order of $CaSO_4$ > $CaCl_2$ > $MgCl_2$ > mixed > GDL > Milky-Mg, springiness, gumminess, and brittleness were highest in the tofu coagulated with Milky-Mg. For the overall acceptability of the sensory properties, the Kanghwang tofu that was made using the mixed coagulant had the highest score.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.363-369
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• 2014

This study was conducted to investigate the quality characteristics of tofu prepared with addition of cowpea meal (CPM). Any significant difference of L-value between control CPM-O and treatment CPM-I, CPM-II and CPM-III could not be seen as addition ratio of CPM increases (p < 0.05). The b-value of CPM-III (75%) has shown the least value of 14.26, and it has decreased as addition ratio of CPM increases. The result of texture profile did not show any significant difference between control CPM-O and CPM-Iexcept in the case of cohesiveness. The pH range of treatments was 6.36~6.52, which showed no significant difference from controls. The values of turbidity were 1.46~1.81, which had increasing trend as addition ratio of CPM increases. The total bacterial count of CPM-III was $4.40{\times}10^2CFU/g$, which showed significant difference from the control. No Esterichia coli was detected in the control and the treatments. The result of sensory analysis of the treatment CPM-I did not show any significant difference from the control, which implied the treatment CPM-Iwas found to be suitable at the tofu making using byproducts of cowpea-jelly making. Isoflavone glycoside (IG) was contained more on the order of genistin, daidzin, and glycitin, and the content decreased significantly as addition ratio of CPM increases. The content of isoflavone-aglycone (IA) was less than IG, but showed similar behavior of addition ratio of CPM.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.10-21
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• 2014

This study is conducted to investigate the effects of Chinese artichoke powder on the antioxidant activities and the quality characteristics of tofu. Tofus are being prepared with different amounts of Chinese artichoke powder in ratios of 0, 0.2, 0.4, 0.6 and 0.8% according to the soy milk quantity. According to the increasing contents of Chinese artichoke powder, the yield and turbidity of tofus are significantly increased (p<0.001) whereas the pH levels of tofus are significantly decreased (p<0.001). In terms of color, the L, a and b values are significantly decreased with increasing Chinese artichoke powder concentrations (p<0.001). From the texture profile analysis of the tofus, the chewiness, gumminess and cohesiveness of tofus are significantly decreased (p>0.01) according to the levels of added Chinese artichoke powder content. The contents of isoflavones such as daidzin and genistin are significantly increased with increasing concentrations of Chinese artichoke powder (p<0.001). The microstructure of tofus is being examined by SEM (Scanning Electron Microscope). In the sensory test, the sample which contains 0.4% of Chinese artichoke powder is ranked significantly higher (p>0.001) than the other groups according to several sensory parameters such as appearance, color, flavor, taste, texture and the overall preferences.

• The Korean Journal of Food & Health Convergence
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• v.8 no.4
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• pp.11-21
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• 2022

Spirulina is known to be more useful abroad than in Korea because it contains more protein than Chlorella, the same microalgae. In the past, sources of animal protein were diverse, but since it takes a long time to receive protein along with environmental pollution, we thought that spirulina could attract attention as a new protein source. In this study, application cases were analyzed in foods in the fields of acorn cake, tofu, dumpling skin, fish cake, white bread, pound cake, salad dressing, and yogurt and so on. As a result of centrally analyzing antioxidant and sensory evaluation, it was confirmed that the results were effective enough to develop products in tofu, dumpling skin, fish cake, and pound cake. It is thought that development of food in other fields will be possible if an additive amount that can match the consumer's preference is found by supplementing the mixing ratio. If it is used as a main raw material for existing food rather than as a raw material for health functional food, consumer preference can increase and quality can be further improved, and it can be suggested as a good alternative for an aging society.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1626-1631
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• 2012

Sixty strains of lactic acid bacteria were isolated from kimchi and used as a starter for fermented tofu. Among the isolated strains, strain KL-6 showed antimicrobial activity against various pathogens, antioxidative activity, and viability in artificial gastric juice and artificial bile acid. The selected strain KL-6 was identified as Pediococcus acidilactici KL-6 by morphological and physiological tests, including Gram staining, catalase test, and 16S rRNA sequencing. The fermentation characteristics of tofu with a kimchi ingredient mixture (Control) consisting of red pepper, garlic, ginger, sugar, salt, jeotgal, and juice of chinese cabbage were compared with those of tofus inoculated with strain KL-6 and the kimchi ingredient mixture (TL) or a pre-fermented kimchi ingredient mixture (TPL) for 24 hr at $37^{\circ}C$. The pH levels of all tested tofu samples decreased after 1 week of fermentation, reaching 3.96 (control), 3.97 (TL), and 4.03 log cfu/g (TPL) after fermentation for 14 weeks at $20^{\circ}C$. Total aerobe content of fermented tofu increased until 2 weeks of fermentation, but decreased steadily thereafter. The number of lactic acid bacteria reached $10^6$ cfu/g after 1 week of fermentation in TL and TPL, whereas it took 2 weeks for the control. The number of lactic acid bacteria in all tested tofu samples reached $10^3$ cfu/g after 14 weeks of fermentation at $20^{\circ}C$. Coliform bacteria were not detected in TL or TPL after 1 week of fermentation. The sensory scores of TL and TPL were higher than that of control in terms of taste, flavor, texture, and overall acceptability. The sensory quality of TPL was the best among all tested fermented tofu samples.

• The Korean Journal of Community Living Science
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• v.26 no.3
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• pp.489-498
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• 2015

This study investigates the effects of a China root (Smilax china L.) extract on the chemical and microbiological characteristics and antioxidant activity of the sausage stew sauce and the soft-tofu stew sauce over a 5-week storage period. Commercial sauces were obtained from the market, and samples were prepared using four different concentrations of the China root extract (0% (control), 0.5%, 1.0%, and 1.5%) and stored at $5^{\circ}C$ and $20^{\circ}C$. Over the 5-week storage period, pH and salinity showed slight changes in both the sausage and soft-tofu stew sauces, but there was no significant difference (p<0.05) regardless of the extract amount and temperature. At 5 weeks, there were significant decreases in the total microbial count in groups with the China root extract (p<0.05) for both the sausage and soft-tofu stew sauces at $5^{\circ}C$. Over the whole storage period, no coliform, yeast, and mold were detected in any sample. S. aureus counts were not detected in 1.0% and 1.5% China root groups at $5^{\circ}C$, but 1.00-1.60 log CFU/g was found in the control and 0.5% groups. DPPH radical scavenging activity at 5 weeks showed an increase with an increase in the amount of the China root extract in both sauces. These results indicate that the China root extract inhibited microbial growth during storage as well as scavenging activity and thus that it can be considered to prolong the shelf life of commercial sauces.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.723-727
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• 2004

Qualitative and quantitative PCR methods were performed to examine detection and quantitation of epsps inserted into genetically modified soybean (GMS) in processed foods, soy milk, tofu, and biji (soybean curd residue). Using PCR amplification to produce two (121 and 330 bp) epsps in GMS, detection limits of GMS in soy milk, tofu, and biji containing 0.01% GMS were measured. For quantitative detection, test samples containing 1, 3, and 5% GMS were measured by real-time PCR method. Results show real-time PCR method is applicable to detect GMS quantitatively in processed foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.442-448
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• 2015

The aim of this study was to investigate the effects of guar gum on the rheological behaviors, sensory attributes, and consumer acceptability of soft tofu stew sauce. Five different soft tofu stew sauces were commercially manufactured with various levels of guar gum (0.0, 0.1, 0.2, 0.4, and 0.5%). Twelve sensory attributes of the stew sauces were identified by nine trained descriptive panelists, whereas hedonic levels of the stew sauces were assessed by a group of 51 consumers. Steady flow of the stew sauces were measured by a rheometer. Significant differences were observed in terms of sensory saltiness and viscosity among the products. For the consumer test, 0.1% guar gum-added product was most liked by consumers. Partial least square regression showed sensory shellfish, green onion, and shrimp flavors to be key factors affecting overall acceptability for the stew sauces. For rheological behaviors, 0.0, 0.1, and 0.2% guar gum-added products showed newtonian behaviors ($R^2$=0.99 by power law model), whereas 0.4 and 0.5% products followed pseudoplastic behaviors ($R^2$=0.99 by power law model). Based on the established equivalence table using rheological and consumer data, smaller than 0.0114 ($Pa{\cdot}s$) of the apparent viscosity should be necessary to guarantee 'slightly like' category in a consumer hedonic test. It seems that addition of guar gum not only influenced rheological properties but overall acceptability for the stew sauces.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.12-15
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• 2003

The effect of chlorella addition on quality and shelf-life of soybean curd was investigated. The yield of chlorella soybean curd was the highest with 1.0% (w/w) chlorella addition. Hardness, gumminess, and chewiness of chlorella soybean curd increased, whereas Hunters color values decreased in proportion to amount of chlorella added. No significant differences were observed between the sensory properties of chlorella and ordinary soybean curds. Microbial counts of soybean curd stored in sterilized distilled water as tofu-immersion solution increased, whereas pH decreased during storage at $15^{\circ}C$. After 5 days storage, microbial counts of the soybean curds containing 0.5 and 1.O% chlorella were lower than that of the ordinary soybean curd. These results imply that chlorella is a useful additive to suppress the proliferation of aerobic microorganism in soybean curd at the optimal concentration of chlorella around 1%.