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 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±0.11 in the control to 5.78±0.11 when 0.4% LFP was added) and a significant increase (from 2.60±0.01 in the control to 2.85±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.

This study examined the quality characteristics of Gondre tofu containing 0, 0.1, 0.2, and 0.3% Cirsium setidens powder. Quality and sensory tests of Gondre tofu were performed. The yield rate of tofu decreased with the addition of Cirsium setidens powder. The pH of tofu decreased after the addition of Cirsium setidens powder. During 8 days storage, the addition of Cirsium setidens powder to tofu did not effectively inhibit the number of total aerobic bacteria. The L, a and b values of tofu decreased with increasing amount of Cirsium setidens powder added. In the texture properties, the hardness, cohesiveness, gumminess and brittleness increased, whereas the springiness decreased. The results of sensory evaluation showed that tofu containing 0, 0.1, and 0.2% Cirsium setidens powder had a higher taste, texture preference and overall acceptability than 0.3% Cirsium setidens powder. Therefore, the addition up to 0.2% Cirsium setidens powder positively affects the sensory evaluation of Gondre tofu. The addition 0.2% Cirsium setidens powder might be considered the most appropriate choice for manufacturing Gondre tofu.

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.

In this study, physio-chemical, mechanical, and sensory characteristics of Tofu containing 0, 0.5, 1.0, and 2.0% Adenophora remotiflora powder were examined. In addition, we examined the potential of utilizing Adenophora remotiflora powder as a functional food material by estimating total phenol contents, electron-donating abilities, and hydroxyl radical scavenging activities of the hot water and ethanol extracts of Adenophora remotiflora powder in the range from 0~2.0%. The total phenol content of the ethanol extracts of Adenophora remotiflora powder was 487.93μg/mL while the that of the water extract of Adenophora remotiflora powder was 403.70μ/mL. The electron-donating abilities of the ethanol and water extracts of Adenophora remotiflora powder were 75.37 and 86.10%, respectively. The hydroxyl radical scavenging activities of the ethanol and water extracts of Adenophora remotiflora powder were 65.50 and 66.22%, respectively. We also evaluated the quality characteristics of Tofu containing Adenophora remotiflora powder. In the case of color values, as the level of Adenophora remotiflora powder increased, the values of L (lightness) and a (redness) decreased, whereas that of b (yellowness) increased. In the case of mechanical properties, as the level of Adenophora remotiflora powder increased, hardness, gumminess, and chewiness values increased (p〈0.05), whereas springiness and cohesiveness values decreased (p〈0.05). In the case of sensory evaluation, MPT1.0 scored significantly higher in color, flavor, tenderness, texture, and overall quality. To sum up, Tofu containing 1% Adenophora remotiflora powder showed the highest overall preference.

두부의 주요 가공과정 중의 일반세균, 저온세균, 포자형성세균의 microflora에 대한 정량 및 정성 분석을 통하여 가공 공정 별 미생물 오염 원인을 규명하고자 하였다. 일반세균은 원료 콩에 4.75 log CFU/g 존재하였으나 두유제조 공정에서 가열에 의해 3.55 log CFU/g으로 감소하였고 가열 후 포장두부에서는 2.53 log CFU/g 존재하였다. 저온세균은 원료 콩에 3.55 log CFU/g 존재하였으나 두유제조 공정에서 가열에 의해 0.78 log CFU/g으로 감소하였고 포장 두부의 가열에 의해 사멸되어 완제품에는 검출되지 않았다. 포자형성세균은 원료 콩에 1.75 log CFU/g 존재하였고 제조 공정 중 외부 오염에 의해 혼입된 후 완제품 저장 시 0.58 log CFU/g 수준으로 검출되었다. 두부의 제조 과정 중 원료 콩으로부터 최종 제품까지 총 29속 70종의 세균이 분리 동정되었다. 원료 콩, 두유, 성형벨트, 숨물 plate, 절단용 칼날, 열탕 전 포장 두부, 열탕 후 포장 두부에 존재하는 주요 미생물은 각각 Bacillus spp., Lysinibacillus bronitoleran, Acinetobacter spp., Bacillus spp., Acinetobacter spp., Acinetobacter spp., Staphylococcus spp.로 확인되었다.

본 연구는 두부의 침지수에 AC를 처리하고 저장기간에 따른 품질의 변화를 측정하여 두부의 저장안정성을 조사하고자 수행하였다. 두부 침지액으로는 증류수, 0.05% AC 용액, 0.1% AC 용액 및 0.15% AC 용액을 사용하여 10oC에 저장하면서 pH와 탁도, 색도, 관능검사, 그리고 미생물의 변화를 관찰하였다. 침지액에 AC를 처리한 두부는 대조구와 비교해 보았을 때 pH가 높게 나타났고 저장기간이 늘어남에 따라 두부의 pH가 약간 감소하였다. 대조구에서 탁도는 두부의 저장기간이 늘어남에 따라 급격히 증가하였으나 AC를 첨가한 두부에서는 농도 의존적으로 탁도의 변화가 감소하는 경향을 보였다. 색도를 측정한 결과 AC를 처리한 두부에서 모든 군에서 차이를 나타내지 않았다. 두부의 관능검사에 있어서 저장기간 동안에 AC를 처리한 두부는 관능적 특성을 더 오래 유지하였으나 AC의 첨가율이 높을수록 색에 대한 기호도가 떨어지고 맛에도 영향을 미쳐 전체적 기호도를 저하시켰다. 두부의 씹힘성과 경도는 AC의 첨가율이 높을수록 낮아졌으나 이물감 조성에는 영향을 끼치지 않는 것으로 나타났다. Texture특성을 관능검사를 통해 측정한 결과 경도, 탄성, 검성, 씹힘성은 0.1% AC와 0.15% AC 용액을 침지액으로 사용하였을 때 대조구와 비교해서 낮은 수치를 나타내는 것을 볼 수 있었다. 두부의 저장기간 동안 호기성 세균수는 대조구에서 7일 후 6.00 log CFU/g을 초과하였으나 0.1% AC와 0.15% AC 처리 시에는 미생물의 증식이 효과적으로 억제되어 저장기간이 연장되는 결과를 보였다. 이와 같은 결과로 볼 때, AC의 침지처리는 10oC에서 7일 동안 가공두부의 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다.

Tofu has been playing an important role in people's daily diet in most of Asia and recently in North America due to several health-promoting functions, preventing and treating a number of chronic diseases such as cancer, coronary heart disease and osteoporosis. The objective of this study was to investigate the effect of different levels of yakong incorporation (0, 5, 10, and 15%, w/w) in preparation of firm tofu. Quality parameters such as pH, titratable, moisture content, color, and consumer preference were determined, and their correlations were analysed. There were no significant differences in pH, titratable acidity, and moisture content due to different levels of yakong incorporation studied (p>0.05). A significant decrease in L* and b*-values whereas significant increase in a*-value was observed (p<0.05). Five percent yakong tofu received the most favorable mean scores with respect to color, texture, and overall acceptability. Correlation analysis revealed that yakong incorporation was well correlated with some of physicochemical properties as well as consumer preference.

This study examined the quality characteristics of Jeungpyun prepared with different additions of nano-filtered (NF) tofu whey concentrates. The initial pH values of the Jeungpyun batters ranged from 5.64 to 5.78, and decreased to 4.77-4.98 after 4 hours of fermentation at 35oC. The volume and specific volume values of the control Jeungpyun were lower than those of Jeungpyun samples prepared with 1%, 2%, and 3% NF powder. The color of the Jeungpyun became increasingly greenish-yellow as the NF powder level increased. Hardness and brittleness decreased with increasing NF powder content, while cohesiveness and springiness were not significantly different. Sensory evaluations revealed that as the level of NF powder increased, takju smell and sourness increased, but no significant differences were observed for sweetness and moistness between the control and NF powder groups. In terms of overall acceptability, the results revealed that Jeungpyun can be prepared with up to 1% NF powder in place of rice powder and be deemed as acceptable as a control Jeungpyun product.

The objective of this study was to develop sensory lexicons that can be utilized for various types of tofu such as pressed, unpressed, and tofu made from germinated soybeans, using generic descriptive analysis. In the first phase of the experiment, trained descriptive panelists developed and defined the appearance, aroma, flavor, and texture attributes that are commonly present in tofu. Then, the sensory characteristics of seven types of tofu were analyzed using the sensory lexicons established in the initial stage of the experiment. Four appearance, 6 odor/aroma, 6 flavor/taste, 7 texture, and 4 aftertaste attributes were identified, and reference standards were established for most of the terms in order to facilitate the understanding of the attribute definitions. The intensities of the sensory attributes were measured on a 15-point scale. Statistical analyses, including analysis of variance and principal component analysis, were used for the data. The seven tofu samples showed significant differences in the intensities of 22 attributes. The unpressed tofu samples were generally rated as being high in moistness, easy to cut, silky, and easy to swallow. The pressed tofu, on the other hand, was salty, astringent, beany, hard, and rough in texture. The tofu made with germinated soybeans was characterized as having a strong cooked bean flavor, salty and astringent aftertaste, and hard texture. Overall, the attributes of moistness, easy to swallow, and silkiness showed strong positive correlations; hardness and sticks to teeth were also positively correlated to each other.

To investigate of the recognition and using behavior on the Tofu, 46.3% of male and 53.7% of female adults in Daegu and Kyungbuk area were surveyed. The main results are as follows : 96.4% of the participants usually preferred the Tofu owing to health and about 68.4% of them had purchased Tofu made of domestic soybean. In addition, the responses to 7 questions about the Tofu were also measured on 5 point Likert scale. The item "Tofu is healthy food" and "Tofu is digestive food" were totally received the high point but "Tofu prevents osteoporosis" earned the lowest. Female had generally better knowledge of Tofu than the counterparts. Most participants relatively knew and had eaten common Tofu, soft bean curd, uncurdled bean curd, fried bean curd against functional Tofu such as Tofu added with omija, surimi, spinach, etc. But they intended to eat functional Tofu such as Tofu added with green tea, black sesame, spinach, omija. Furthermore, 60.7% replied "increasing" prospects for the Tofu consumption. 40.0% of adults said the plan should be "Make of good quality domestic soybean" for the purpose of better improvement to consume.

To investigate of the perception and using behavior by age of tofu, 46.3% of male and 53.7% of female about 700 adults in Daegu and kyungbuk area were surveyed. 96.4% of the participants usually preferred the tofu owing to health and 68.4% of them had purchased tofu made of domestic soybean. In addition, the responses to 7 questions about the tofu were also measured on 5 point Likert scale. The item "Tofu is healthy food" was totally received the high point but "Tofu prevents osteoporosis" earned the lowest. Most participants relatively knew and had eaten common tofu, soft bean curd, uncurdled bean curd, fried bean curd against functional tofu such as tofu added with omija, surimi, spinach, etc. But they intended to eat functional tofu such as tofu added with green tea, black sesame, spinach, omija. Furthermore, 60.7% replied "increasing" prospects for the tofu consumption. 40.0% of adults said the plan should be "Make of good quality domestic soybean" for the purpose of better improvement to consume.

오징어 먹물두부의 응고제 종류에 따른 품질 특성을 살펴본 결과는 다음과 같다. 먹물두부의 수율을 GDL 먹물두부가 가장 높았으며, MgCl2, CaCl2 먹물두부가 낮은 수율을 나타내었다(p〈0.001). 그러나 두부 순물의 양은 두부 수율고 반대였다. 먹물두부의 pH는 MgCl2 두부가 가장 높았고, CaCl2 두부가 pH가 가장 낮았다(p〈0.001). 먹물 두부 순물의 pH도 두부의 pH와 같은 결과였다(p0.001). 먹물두부의 산도는 CaCl2 두부가 가장 높았고, 글루콘산 칼슘 먹물두부의 산도가 가장 낮아 유의적인 차이가 있었다(p〈0.001). 먹물두부 순물의 탁도는 CaSO4, 글루콘산 칼슘, CaCl2 먹물두부 순으로 높았고, GDL 두부의 탁도가 가장 낮았다(p〈0.001). 수분함량 측정 결과 MgCl2 두부의 수분이 가장 많았고, CaCl2 두부의 수분이 가장 작게 나타났다(p〈0.001). SEM을 이용한 미세구조 관찰에서 GDL 두부와 글루콘산 칼슘 두부의 망상구조가 다른 응고제를 사용한 두부보다 크기가 작고 균일했다. 먹물두부의 관능검사 결과 외관의 기호도, 맛의 기호도에서 GDL 먹물두보가 가장 높은 점수를 얻었으며, 질감의 기호도 역시 GDL 먹물두부가 가장 높았다. 전반적인 기호도는 GDL, 글루콘산 칼슘 먹물 두부 순으로 높게 나타나 수용도가 높았다. 먹물두부의 색도 측정 결과 명도 L값과 적색도 a값은 GDL 먹물두부가 가장 높았고, 황색도 b값은 CaCl2 두부가 가장 높았다(p〈0.001). 먹물 두부의 texture 측정에서 견고성, 껌성, 파쇄성은 글루콘산 칼슘 두부가 가장 높았다. GDL 두부는 견고성은 가장 낮았으나, 응집성은 가장 높게 나타났다. 이화학적 평가간의 상관관계 결과 두부 순물의 pH가 높을수록 산도는 높아지고, 탁도는 낮아졌다. 산도는 탁도, 수분함량과 부의 상관관계가 있었다. 관능검사와 기계적 검사간의 상관관계에서 수분함량은 다른 관능검사 항목과 부의 상관관계를 나타내었다. 기호도와 관능항목간의 상관관계 결과 전반적으로 구수한 향이 강하고, 응집성, 탄력성이 높을수록 기호도가 높게 나타났다.

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℃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.

This study is to investigate the recognition and preference of tofu food among general consumers and housewives in order to develope new tofu menu. The questionnaires are consisted of general questions, style of dining out, frequency of dining, health status, preference of tofu, reason for prefer tofu. A total of 262 questionnaires were analyzed for statistical analysis. The statistical analysis was completed using SAS program (Version 8.2) for descriptive analysis and χ2 -test. Main results of this study were as follows: Most of the respondents prefer Korean food, 70% of the respondents are general consumers while 73.5% of the respondents are housewives. The frequency of dining out was 1-2 times per week. The two groups bought pre-cooked food one to two times per week. Fourity seven percent of the general consumers and 50% of housewives did not like the taste of tofu due to plain flavor. The respondents overall preferred many different ways to prepare tofu dishes. The results also indicated that tofu dishes are used as side-dishes. Thirty three percent of house wives had tofu with miso soup and pan-fried tofu, while 29.6% of the general consumers had soft tofu stew. 34% of the general consumers preferred stuffed tofu with shrimp, while 35.5% of the housewives liked it. 17% of the general consumers liked grilled tofu with crab meat sauce while only 14.5% of the housewives preferred the menu. Tofu teriyaki was preferred among 8.2% of the general consumers while 13.2% of the housewives liked tofu teriyaki.

검정콩 종피를 첨가하여 제조한 두부의 품질특성을 검토하였다. 황색콩과 검정콩 전체를 분쇄하여 가공한 두부의 수득량과 두부순물의 수득량은 거의 동일한 양상을 나타내었으나, 0.5% 및 5%의 검정콩 껍질을 첨가하여 두부를 제조한 경우 첨가된 껍질로 인해 황색 및 검정 두부에 비해 두부의 수득량이 뚜렷이 증가하였다. 특히, 5% 검정콩 껍질의 첨가 시에 황색과 검정 두부에 비해 1/2수준의 두부순물이 감소하였다. 두부의 물성검사에서는 검정콩 종피를 5% 첨가한 두부에서 응집성, 점착성, 씹힘성이 높은 양상을 나타내었으며, 황색콩과 0.5% 검정콩 껍질 첨가 두부 간의 물성을 비교한 결과는 점착성과 씹힘성에서 유의적인 차이가 나타나지 않았다. 이는 기존 두부의 가공비율 대비 0.5% 수준으로 검정콩 종피를 첨가하여도 가공된 두부의 견고성과 씹힘성에는 영향을 미치지 않는다는 결과를 추정할 수 있다. 또한 관능평가에서는 조직감(texture), 견고성(firmness)에서는 황색콩, 검정콩, 0.5% 검정콩 껍질 첨가 및 5% 검정콩 껍질 첨가 두부 간에 유의적인 차이가 나타나지 않았다. 두부 특유의 고소한 맛은 0.5% 검정콩 껍질을 첨가한 두부에서 가장 좋은 풍미를 나타내었으며, 5%검정콩 껍질 첨가 두부에서 가장 낮았다. 두부 저장기간에 따른 일반 세균수와 진균수를 측정한 결과는 5% 검정콩 껍질 첨가 두부에서 황색콩, 검정콩, 0.5% 검정콩 껍질 첨가 두부에 비해 균의 증가가 억제되는 양상을 보였다.

A amylase producing bacteria were isolated from tofu residue and identified as Bacillus sp. according to the morphological and biochemical properties, which were named Bacillus sp. GM7330 and Bacillus sp. GM7312. The cultural condition for the production of amylase was showed on 5% tofu residue added 3% glucose and 0.15% yeast extract. And incubated during 72 hrs at 30℃, Bacillus sp. GM7330 and Bacillus sp. GM7312 were producing amylase of 488 units and 341 units.

This study was undertaken with packed tofu products to serve as a basic source for sanitary control of tofu production by detecting spoilage bacteria in tofu from which are isolated, investigating heat-resistance and growth characteristics of spoilage bacteria. Isolated strains were confirmed as relevant strains in tofu spoilage, and Strain No. Tl, T2 show 92% probability to be Enterobacter amnigenus, and 96% to be Flavobacterium indologenes according to the result of identifying strains by using Vitek system. Both strains had high viability at 35℃, pH 6.5. In the heat-resistance test of isolated strains, Enterobacter amnigenus T1 was treated for 2 mins, the number remained 56.3% of the initial number at 60℃, 37.8% at 70℃, 34.0% at 80℃ and 22.2% at 90℃, and Flavobacterium indologenes T2 was treated for 2 mins, the number remained 74.8% of the initial number at 60℃, 65.7% at 70℃, 37.8% at 80℃ and 9.3% at 90℃.