• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.53-58
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• 1996

The characterstics of the soy protein curd(eczyme-, HCI- and Ca-surd) were shown by scanning electron micrographs and gel electrophoreis. The emulsion stability of enzyme-curd showed high value in the range of pH 2~10and wide range of temperature(20~8$0^{\circ}C$). While at the isoelectric point(pH5.0), the emulsion stability of the HCI-and Ca-curd was decreased remarkably, and the emulsion stability of temperature was reduced quickly to the 60% and 40% at the 4$0^{\circ}C$. The foam stability of enzyme-curd was slightly higher than that HCI-and CA-curd in all ranges of pH and temperature. The feature of SEM of enzyme-cured produced degradation products faster than that of the HCI- and Ca-curd.

• 한국식품영양과학회지
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• 제23권6호
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• pp.973-979
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• 1994

Microorganisms, including the strain IJ-3 isolated from soil, were found to secrete an extracellular soybean protein coagulating enzyme and the strain, IJ-3 was identified as Genus Bacillus according to the Bergey's manual . The enzyme coagulated protein in soymilk , thus forming a curd at pHs 5.8-6.4 and at 55-75℃. The optimum temperature for soybean protein coagulating activity was 65-75℃ and the enzyme was stable at temperature below 50℃ and was found to be stable with about 60-100% of the original activity at a with pH ranges(pH6-7). The molecular weight of enzyme was estimated to be 28,000 by SDS-PAGE. The curd formed with the enzyme from Bacilus sp. IJ-3 has a smooth texture, and a mild taste without any bitterness or a beany flavor.

• 한국조리학회지
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• 제3권
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• pp.327-341
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• 1997

Food materials usually contain much water, and thus are susceptible to decay be enzyme and microorganism. Cereals are usually consumed as staple food, but they have low protein content. Protein is a major component of body, and should be consumed as a nutrient for all ages. Animal protein like chicken and vegetable protein such as bean curd and soybean and good sources of high quality protein. Bean curd is a traditional food which have good nutrients, and so various cooking methods are needed to be developed for the supplement of high quality food. 1) Cereals such as rice, barley, and bean curd, soybean, green vegetables, tangle and brown seaweed are known as food for long life. 2) Soybean is able to suppress the formation of hydroperoxide by saponin and lecithin. 3) Curd in bean curd means soft in Chinese character, and bean curd may be the mother of cheese. 4) Bean curd have high nutrition and digestibility. As soybean is dipped longer in water for bean curd, the production rate is higher. 5) There are many kinds of bean curd products, and can be purchased inexpensively.

• 한국식품영양과학회지
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• 제22권5호
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• pp.643-649
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• 1993

대두의 조성은 다른 두류나 곡류와는 달리 35~40%의 단백질, 15~20%의 유지 및 20~25%의 당을 함유하고 있다. 예로부터 대두는 두부, 간장, 된장과 같은 전통식품의 원료로써 넓게 쓰여져왔다. 초원심분리에 의한 대두 단백의 성분은 침강정수에 의해 2, 7, 11 및 15S의 4가지 주요한 성분으로 나타난다. 저당잔백질 중 중요한 2성분인 7S 및 11S globulin은 많은 연구자들에게 의해 분리되고, 특성이 알려졌다. 미생물 효소에 의해 제조된 응고물은 금속이온 및 산처리에 의해 만들어진 것보다 훨씬 조밀한 구조를 나타내었다. 효소작용으로 얻어진 curd는 식품재료로써 개발되어지고, 식품가공분야에서도 폭넓게 이용될 것으로 기대된다.

• Preventive Nutrition and Food Science
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• 제2권3호
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• pp.259-262
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• 1997

The microstructures of soybean milk curds, prepared by different coagulation methods, were observed by the scaning electron microscope. Th curd coagulated by theaddition of bacerial soybean mil clotting enzyme showed little textural changes and gave smoother gel than those prepared either by lactic acid fermentation using Streptococcus thermophilus or by the addition of CaSO$_4$. The curds obtained by lactic acid fermentation and by the addition of inorganic salt exhibited three dimensional network structure which indicated harder gel than that prepared by soybean mil clotting enzyme.

• Asian-Australasian Journal of Animal Sciences
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• 제23권10호
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• pp.1369-1379
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• 2010

This study investigated purification and milk-clotting activity of the enzymes produced by Bacillus subtilis var, natto and Rhizopus oligosporus compared with that of commercial rennet. The clotting time, viscosity, tension and microstructure of the curd and electrophoretic patterns of milk proteins were determined. The milk-clotting activity/proteolytic activity ratios (MCA/PA ratio) of B. subtilis, R. oligosporus and commercial rennet were also compared. The results revealed that the curd formed by the commercial rennet had the highest viscosity and curd tension and the shortest clotting time among the three enzymes. However, curd produced by Rhizopus enzymes was ranked as second. From the MCA/PA ratio and electrophoretogram analyses it could be concluded that the enzyme produced by B. subtilis had the highest proteolytic activity, while the commercial rennet had the highest milk-clotting activity. Observations of microstructures of SEM showed that the three-dimensional network for curd formed by commercial rennet was denser, firmer and more smooth. The milk-clotting activity, specific activity, purification ratio and recovery of the purified enzymes produced by both the tested organisms were also determined with ion exchange chromatography and gel filtration.

• 한국식품영양과학회지
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• 제34권6호
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• pp.904-909
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• 2005

일본 청국장에서 분리된 Bacillus firmus NA-1를 이용하여 비지의 수분함량, 생대두미세분말첨가 및 발효시간에 따른 비지 발효물의 혈전용해효소, 점질물, 펩타이드생산 및 풍미 개선 효과를 알아보았다. 비살균 D-비지는 30시간 이상부터 청국장 발효가 진행되는 반면, 살균 D-비지는 18시간부터 고초균 발효에 의하여 pH가 증가하였으며 혈전분해효소, 펩타이드 함량이 비살균 D-비지보다 높은 값을 보였다 P-비지의 경우는 18시간 발효시에 가장 높은 pH, tyrisone 함량과 혈전용해효소활성을 나타냈다. 또한 P-비지를 건조하여 초기수분함량을 $60\%$로 낮추었을 때 발효비지물의 펩타이드 함량과 혈전용해분해효소활성이 증가하였다. p-비지에 전지활성 생대두미세분말을 $10\%$수준으로 첨가함으로써 혈전분해효소 및 펩타이드 함량이 증가되는 효과를 보였으며, 점질물의 생성에 따른 점조도 값의 증가를 나타내었다. 특히, 콩미세분말을 $20\%$ 수준으로 첨가하여 발효시킨 비지는 고유한 청국장의 풍미를 나타내었으며, 건조시킨 발효비지물의 조단백질함량은 $27.3\%$를 나타내었다. 따라서 비지의 고초균 발효시에 전지활성 생대두미세분말의 첨가는 비지의 초기수분함량을 낮추면서, 고초균 발효의 촉진을 통한 콩 펩타이드 및 혈전용해효소의 증가, 점질물 생산, 풍미 개선을 비롯하여 발효비지의 단백질 보강이 가능하였다.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.397-404
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• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.

• Asian-Australasian Journal of Animal Sciences
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• 제14권10호
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• pp.1470-1476
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• 2001

Kou Woan Lao is an oriental-style dairy product, which is coagulated by milk-clotting enzyme from the culture filtrate of lao-chao. The product appears smooth, sweet, slightly wine flavour, and the flavour differs from yogurt. The aim of this study was to search for the optimum model to shorten the period of manufacture, and to improve the quality of Kou Woan Lao. A response surface design was used for studying the effects of addition of carrageenan, locust bean gum, and culture filtrate from lao-chao on the curd firmness, viscosity, and syneresis. Results indicated that the best rheological property, preservative quality and acceptability of Kou Woan Lao could be obtained by the combination of 0.22% carrageenan, 0.21 % locust bean gum and 12% culture filtrate from lao-chao. The curd firmness, viscosity and syneresis of resultant product were 29.3 g, 21,347.7 cps, and 8.92%, respectively and the microstructure of the curd revealed a relatively complete three-dimensional spider web-like structure.

• 한국식품과학회지
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• 제24권3호
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• pp.294-299
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• 1992

본 연구에서는 분리대두단백질에 단백질 가수분해효소를 처리하여 대두단백질에 가수분해적 변성을 야기하여 그 기능성을 변화 고찰하고 실제 식품에의 이용방법으로 효소처리된 두유로 두부를 만들어 물성실험과 관능평가를 실시하였다. 장엽에서 SPI를 제조한 후 15분간 bromelain으로 처리하여 2.7% 가수분해된 MSPI를 만들어 기능특성을 측정 비교하였다. MSPI는 전 pH범위에서 용해도가 증가하였고, 특히 등전점에서 15% 정도 증가하였다. 유화형성력과 기포팽창력은 증가하였으나 이들의 안정성은 감소하였는데, 특히 기포안정성은 알칼리쪽에서 급격히 감소하였고, 등전점에서는 가장 큰 것으로 나타났다. 표준두유와 변형두유를 혼합하여 제조한 두부로 물성실험과 관능평가를 실시하였을 때 압착실험에서는 변형두부I이 연하고 탄력성 있는 두부를 형성하는 것으로 나타났다. 각 두부의 물성모형은 spring 한개와 Maxwell 모형 세개를 가진 7요소모형으로 동일한 물성모형을 나타내었다. 관능평가에서는 표준두유와 변형두유를 3 : 1의 비율로 혼합하여 제조한 두부의 품질이 가장 우수한 것으로 평가되었다.