• 미생물학회지
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• 제54권2호
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• pp.113-125
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• 2018

본 연구에서는 히스타민을 생성하는 유산균과 이에 항균 활성을 나타내는 프로바이오틱 유산균을 혼합 접종하여 제조한 렌넷 커드 내 항균물질과 히스타민 생산에 영향을 미치는 인자를 조사하였다. 프로바이오틱 유산균인 Lactobacillus plantarum FIL20과 Lactobacillus sakei PIL52는 히스타민 생성균인 Lactobacillus brevis LAS129, Enterococcus faecium SBP12 및 Enterococcus faecalis SBP58에 대해 강력한 항균 물질을 생산하였고, 프로바이오틱균이 생산한 유산과 박테리오신의 항균 활성은 농도의존적이었다. 렌넷 커드 제조를 위해 접종한 프로바이오틱 유산균의 균수가 많을수록 항균 물질 생성량이 증가되어 히스타민 생성균에 대한 항균 활성도 높아졌다. 프로바이오틱 유산균과 히스타민 생성균은 NaCl 10% 첨가에 의해 증식이 억제됨으로써 렌넷 커드 내에 항균 물질과 히스타민의 함량은 대조구보다 유의하게 낮았다(P < 0.05). 한편, 프로바이오틱 유산균과 히스타민 생성균을 혼합하여 제조한 렌넷 커드를 $25^{\circ}C$에서 5일간 저장 했을 때 히스타민의 함량은 유의하게 증가되지 않았으나, $20^{\circ}C$에서 20일간 저장한 경우에는 프로바이오틱 유산균이 생산한 항균 물질의 활성이 감소됨에 따라 렌넷 커드 내에 히스타민의 함량이 유의하게 증가되었다(P < 0.05).

• 좋은식품
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• 통권20호
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• pp.30-43
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• 1974

• 좋은식품
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• 통권19호
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• pp.25-35
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• 1974

• 좋은식품
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• 통권18호
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• pp.42-55
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• 1974

• 한국축산식품학회지
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• 제26권3호
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• pp.368-374
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• 2006

We have studied on characterization and cheese making like mineral contents, protein composition and coagulation pattern on equine milk. At first, for contents of mineral on equine milk, It was lower in equine than bovine milk Contents of Na, Mg, P, Ca and K the major minerals, were indicated as 18.3 mg, 0.4 mg, 33.3 mg, 80.9 mg and 134.9 mg respectively by 100 g. In the distribution of nitrogen, the ratio NPN to Nt was indicated as 9.8% while that of bovine milk was 7%. And In NCN, its percentage was indicated as 45.6% shelving that Equine casein was lower than bovine. From these results, equine milk could not be applicable to cheese production since there are no coagulable nitrogen fraction such as ${\kappa}$-casein, as there aye with bovine milk. Equine milk will be more acceptable if we accept that the phylogenic affinity is near to human. It is the same as equine from the view points that monogastric, which did not contain ruminant's casein. For the rennet coagulation, equine milk was different than bovine milk. Equine milk did not coagulated by rennet after the addition of $Ca^{2+}$. But when bovine ${\kappa}$-casein was added in the presece of rennet, and $Ca^{2+}$ to equine milk, coagulation occurred. Such phenomenon was also observed by the use SEM. Verification of ${\kappa}$-casein by SDS-PACE did not existed in equine milk. The Casein of equine milk(54.4%) is similar to human milk in that casein/whey is about 1. For equine milt this can be explained because distance between casein and Ca is great, casein being lower, which result in reaction of casein with $Ca^{2+}$ because it could not activated which lasting time of coagulation is too long.

• 농업과학연구
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• 제14권1호
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• pp.144-155
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• 1987

토양(土壤) 및 하수(下水)에서 단백분해활성(蛋白分解活性)이 약하고 응유활성(凝乳活性)이 강한 SA-101 균주(菌株)를 분리(分離), 선정(選定)하여 Mucor sp. 동정(同定)하였다. 사용균주(使用菌株)에 의한 응유효소생산(凝乳酵素生産)은 밀기울 10 g에 0.1M HCl 을 함유한 수도수 8 ml를 가하여 $30^{\circ}C$에서 60시간의 배양(培養)이 가장 좋았다. Lactose 6%, NaCl 0.05%를 첨가(添加)하였을때 효소생산(酵素生産)이 촉진(促進)되었고 밀기울 g당(當) 9,810 단위(單位)의 효소생산(酵素生産)을 보였다. 유안염석(硫安鹽析)과 동결건조(凍結乾燥)등으로 조제한 조효소제품(粗酵素製品)의 MCA/PA비(比)는 Hansen rennet 보다 낮았으나 Meito rennet과 유사하였고 응유활성(凝乳活性)의 최적온도(最適溫度)는 1/100M $CaC1_2$를 함유한 10% 환원탈지유(還元脫脂乳)를 기질로 하였을 때 $60^{\circ}C$ 부근이었다.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2003년도 제31차 춘계 학술대회
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• pp.175-175
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• 2003

• Food Science and Biotechnology
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• 제17권1호
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• pp.58-65
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• 2008

To see the possibility of irradiation as an alternative to ultra high temperature (UHT) sterilization, the quality characteristics of milk were analyzed. Milk treated by UHT ($135^{\circ}C$ for 4 sec) and irradiation at higher than 3 kGy showed no viable counts after 7 days of storage at $4^{\circ}C$. The contents of certain amino acids of milk, such as Arg, Asp, Glu, Ile, Leu, Lys, Pro, Ser, Thr, and Tyr, were lower in irradiated groups at 10 kGy than in UHT-treated one, but no difference was observed between irradiated milks at less than 5 kGy and UHT. The capillary electrophoresis (CE) patterns of the milk irradiated at 10 kGy showed a similar trend to the raw milk, low temperature long time (LTLT, $63^{\circ}C$ for 30 min), and high temperature short time (HTST, $72^{\circ}C$ for 15 sec) treated. However, the CE pattern of UHT-treated milk was different. Rennet coagulation test agreed with the CE results, showing that all milk samples were coagulated by rennet addition except for UHT-treated milk after 1 hr. These results suggest that irradiation of milk reduce the content of individual amino acids but it may not induce severe conformational change at a protein level when compared with UHT treatment.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1212-1217
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• 2003

Fifty-two Holstein cows with different phenotypes of $\kappa$-casein ($\kappa$-CN) and $\beta$-lactoglobulin ($\beta$-LG) were selected to provide weekly milk samples for heating at 30, 70, 75 and $80^{\circ}C$ for 2 min. Coagulating properties of heated milk samples measured as rennet clotting time, rate of curd firming and curd firmness at cutting were determined by a Formagraph. Milk samples were analysed for fat and casein. Least squares analyses of data, after adjustments were made for effect of milk casein and fat contents, indicated that although an increase in heating temperatures resulted in less desirable coagulating properties, the effect of milk types was inherent irrespective of heating temperatures. The shortest rennet clotting time (6.06 min), fastest rate of curd firming (5.61 min) and firmest curd (38.05 mm) were obtained from milk with the B variant for $\kappa$-CN and B variant for $\beta$ -LG when preheated at $30^{\circ}C$. It appears that milk bearing $\kappa$-CN B is more resistant to heat perturbation. All milk samples having the $\kappa$-casein AA (milk types AA/AA, AA/AB, AA/BB) did not have a measurable K20 value when preheated at $70^{\circ}C$. This effect was observed for $\kappa$-casein AB (milk types AB/AA, AB/AB, AB/BB) at $75^{\circ}C$ and $\kappa$-casein BB (milk types BB/AA, BB/AB, BB/BB) at $80^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• 제29권9호
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• pp.1363-1370
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• 2016

Rennet, a complex of enzymes found in the stomachs of ruminants, is an important component for cheese production. In our study, we described that yak chymosin gene recombinant Pichia pastoris strain could serve as a novel source for rennet production. Yaks total RNA was extracted from the abomasum of an unweaned yak. The yak preprochymosin, prochymosin, and chymosin genes from total RNA were isolated using gene specific primers based on cattle chymosin gene sequence respectively and analyzed their expression pattern byreal time-polymerase chain reaction. The result showed that the chymosin gene expression level of the sucking yaks was 11.45 times higher than one of adult yaks and yak chymosin belongs to Bovidae family in phylogenetic analysis. To express each, the preprochymosin, prochymosin, and chymosin genes were ligated into the expression vector $pPICZ{\alpha}A$, respectively, and were expressed in Pichia pastoris X33. The results showed that all the recombinant clones of P. pastoris containing the preprochymosin, prochymosin or chymosin genes could produce the active form of recombinant chymosin into the culture supernatant. Heterologous expressed prochymosin (14.55 Soxhlet unit/mL) had the highest enzyme activity of the three expressed chymosin enzymes. Therefore, we suggest that the yak chymosin gene recombinant Pichia pastoris strain could provide an alternative source of rennet production.