• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.177-181
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• 2005

근원섬유 단백질에 카제인염을 첨가함으로써 유화안정성이나 보수력을 증진시킬 수 있으나 가제인염은 열에 안정성이 떨어지는 단점을 가지고 있다. TGase가 이러한 카제인염의 단점을 보완해주는지 알아보기 위해 열량분석기와 전기영동을 이용하여 단백질의 변화를 측정하였다. 열량분석기의 경우 근원섬유 단백질과 카제인 염 단백질의 상호교차결합을 TGase의 첨가유무에 따라 실시하였으며 그 결과 TGase의 첨가는 각 단백질 열량변화가 나타나는 온도를 변화시켰으며 배양시간을 증가할수록 각 단백질별 열량변화의 차이를 보였고 peak의 크기에도 차이를 보였다. 또한 전기영동의 경우 MFP, SC, MFP:SC의 1:1 혼합액을 각각을 TGase 첨가한 것과 하지 않은 것을 비교한 결과, TGase의 첨가는 고분자 polymer를 만들어줌으로써 두 단백질간의 상호작용에 촉매제로써 작용한다는 것을 확인하였다.

• 베이커리
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• no.9 s.362
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• pp.76-81
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• 1998

• Korean Journal of Poultry Science
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• v.37 no.1
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• pp.69-80
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• 2010

Hypocholesterolemic effect of soy protein was examined in comparison with casein and three other dietary protein sources in chicks. In two feeding trials, 40 (Expt.1) or 50 (Expt. 2), three-day-old, male chicks were forced-fed each of five semi-purified-type diets containing isolated soy protein (ISP, cp 82%), casein (cp 92%), rice protein (RP, cp 70%), corn gluten meal (CGM, cp 65%) or fish meal (FM, cp 70%) for two weeks. The diets for Expt. 2 were supplemented with 0.3% cholesterol by replacing glucose. Each protein source was the only source of protein of each diet. Essential amino acids were added to the diets to satisfy their requirements according to NRC. The diets were forced-fed to equalize the intake of all nutrients except the amino acids which were inherently variable in the diets. Chicks fed casein showed lower body weight gain than those fed the other proteins in both experiments. Birds fed ISP and FM gained better body weight than the others. Chicks fed casein showed significantly higher levels of plasma total cholesterol, non-HDL cholesterol and triacylglycerol (TG) than those fed ISP and the other protein sources. Meanwhile, the chicks fed ISP, RP, CGM and FM showed comparable levels of plasma total cholesterol, non-HDL cholesterol and TG. In Expt. 2, the birds fed casein and FM showed markedly elevated plasma total cholesterol and non-HDL cholesterol levels. Liver weight and levels of total lipids and cholesterol of chicks fed casein appeared significantly higher than those of the other protein diets, whereas those of the chicks fed ISP, RP, CGM and FM appeared comparable except cholesterol in FM group. In conclusion, only the chicks fed casein diets in both experiments always showed significantly higher levels of plasma cholesterol and TG compared to those fed ISP and the other protein sources. These results support the views that casein, which has unique lysine-arginine ratio, is inherently hyper-cholesterolemic, and ISP is hypocholesterolemic only when compared to casein.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.479-483
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• 1994

The effects of the different protein source on serum cholesterol levels were studied in SD strain male rats. Fish protein prepared by the method of SUZUKI from Alaska Pollack (Theragra chalcogramma) was compared with casein and soybean protein isolate. Each protein source was incoporated into a cholesterol-free diet in order to provide a protein level of 20% for 2 weeks. The result obtained are as followed: Concentration of total-cholesterol, LDL-cholesterol, total-cholesterol/HDL-cholesterol and triglyceride in rats fed with fish protein group were significantly lower than those of rats fed with casein and similar to those of rats fed with soybean protein. In addition, it was shown that the ratio of Lys/Arg and Gly/Met+Cys of fish protein was close to that of soybean protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.73-83
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• 1983

This experiment was conducted to study effects of different sources of protein, and of the different combination ratios of the two protein supplemented or unsupplemented with methionine on the growth and body metabolism of the growing male rats. Casein and isolated soyprotein (ISP) were combined at different ratios of 100:0, 80:20, 50:50, 20:80 and 0:100 to supply the constant levels of dietary energy and protein of 3,600kcal/kg and 20%, respectively. Each combination was supplemented with either 0 or 0.3% methionine. Results obtained in these experiments were summarized as follows: The body weight and weight gain in the ISP diet were the lowest, but were increased with the increase of ratios of casein to ISP. The body weight gain in the ISP diet supplemented with methionine was similar to that in the combination diets of casein and ISP. The combination diets of casein and ISP supplemented with methionine had the higher weight gain than the casein diet. The food intake in the casein diet was the highest, and was increased with the increase of ratios of casein to ISP, and was lowered with methionine supplementation. The food intake in the ISP diet was the lowest and was not increased with methionine supplementation to the ISP diet. The food efficiency ratio of the combination diets of casein and ISP was improved compared to those of either the casein or the ISP diets. The food efficiency ratio was improved in the diet of either casein of ISP supplemented with methionine, but was not improved in the combination diets of casein and ISP with methionine supplementation. The gross energy intake had direct relation with the food intake of rats and the relation was increased either in the casein diet of with the increase of the ratios of casein to ISP. The energy efficiency and protein efficiency ratios were improved in the diet of either casein of ISP by the supplementation of methionine, and the effect of methionine supplementation of the energy efficiency and protein efficiency atio was increased with the increase of the ratios of ISP to casein. The nitrogen intake and urinary nitrogen excretion of the casein diet were the highest and those of the ISP diet were the lowest. They were increased with the increase of ratios of casein to ISP. The nitrogen balance and retention were not significantly among the treatments. The gross energy intake and fecal and urinary energy were the highest in the casein diet but the digestible and metabolizable energy and the digestibility and metabolizability of energy were not significantly different among the treatments. The body fat content of rats was increased by supplementation of methionine but the body protein content was decreased (r=-0.65, p<0.01). The body fat content of rats was negatively correlated with body moisture content (r=-0.83, p<0.01). The liver weight was highly correlated with the carcass weight (r=0.79, p<0.01), and was increased by the methionine supplementation and by the increase of the ratios of casein to ISP.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.221-225
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• 2005

본 연구는 식염첨가의 감소를 MTGase와 우유단백질을 첨가하여 보완하기 위하여 저지방 저염 재구성 햄을 제조하여 이화학적 및 조직학적 성상을 평가하였고, 1.5%의 식염이 첨가된 대조구와 기능성, 조직감 및 관능성을 비교하였다. 제조한 재구성 햄의 pH, 그리고 수분, 지방 및 단백질 함량은 각각 6.07-6.22, 68-72%, 2-5%, 18-22%였다. 색도와 보수력은MTGase와 우유단백질 첨가에 의해 영향 받지 않았다 (p>0.05). 반면에 가열감량은 식염첨가량과 우유단백질에 의해 차이를 보여 식염함량이 증가할수록 가열감량은 낮았고 카제인 염이 유청 단백질에 비하여 가열감량을 줄일 수 있었다 (p<0.05). 조직검사에서는 MTGase에 우유단백질 1%를 첨가한 처리구가 대조구에 비교한 결과, 경도를 제외한 조직검사에서 높은 값을 나타내었다. 관능평가에서는 1.0% 식염에 0.3% MTGase와 1% 우유단백질을 첨가한 재구성 햄이 기능적에서 대조구와 유사하였다. 이러한 결과는 0.3% MTGase에 1% 우유단백질을 첨가하는 것이 식염감소에 의한 재구성 햄의 결점을 보완함을 시사하였고 카제인 염 단백질은 MTGase의 기질로써 유청 단백질보다 더 효율적이었다.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.154-159
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• 2008

To investigate the rheological properties of protein mixed gels mediated by microbial transglutaminase (MTGase), pork myofibrillar protein (MFP), sodium caseinate (SC) and their mixture (MS), the various gels were incubated at different temperatures for various times. Extracted MFP, SC and their mixture (MS, 1:1) were incubated at different temperatures ($4^{\circ}C$ vs $37^{\circ}C$) for various times (0, 0.5, 2, 4 hr), and assessed for viscosity, gel strength and other characteristics using differential scanning calorimeter (DSC) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). DSC measurements showed that incubation at $37^{\circ}C$ rather than $4^{\circ}C$ caused marked changes in thermal transition, and MS displayed similar thermal curves (three endothermic transitions) to MFP and SC alone. After incubation at $37^{\circ}C$ for 2 hrs, the viscosity (cP) of MS increased (p<0.05) due to induction by MTGase, whereas no differences were observed at $4^{\circ}C$. However, gel strength values were no different, regardless of incubation temperatures and times. Future research will address how longer incubation times affect the functionality of protein mixed gels mediated by MTGase.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.170-174
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• 2006

근육 단백질과 우유 단백질간의 상호작용의 촉매제로써 TGase의 최적화를 위한 온도와 배양시간을 결정하고자 본 실험을 실시하였다. 돼지 등심에서 근원섬유 단백질을 추출하였고 배양온도는 4, $37^{\circ}C$로, 배양시간은 0, 0.5, 2, 4시간으로 설정하였다. 단백질의 열량분석, 점도, 겔 강도, 단백질 밴드의 변화를 측정하였으며, 그 결과 단백질 열량 변화는 각 단백질 별로 열량 변화 패턴이 상이하게 나타났으며 근원섬유와 카제인 염의 혼합액은 각각의 단백질의 피크와 유사하게 나타났고 배양시간과 온도에 따라 차이를 보여 $4^{\circ}C$에 비하여 $37^{\circ}C$에서 열량 변화가 크게 나타났다. 점도의 경우 배양하지 않은 것과 비교했을 때 $37^{\circ}C$에서 2시간 배양했을 때부터 유의적인 차이를 보이며 증가했으나 4시간 배양한 것과는 차이를 나타내지 않았다. 전기영동의 경우에도 $37^{\circ}C$에서 30분 배양한 처리구는 큰 변화를 나타내지 않았으나 2시간부터 저분자의 밴드가 소멸되고 고분자의 biopolymer를 형성되었다.

• Journal of Life Science
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• v.9 no.1
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• pp.35-43
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• 1999

Leaf protein (LP) was prepared by centrifugation the green juice from Italian ryegrass (Lolium multiflorum Lam.) at acid precipitation. LP was compared with casein and soybean protein isolate for their concentration of serum lipids and free amino acids in Wistar male rats for 2 weeks. Each protein source was incoporated into cholesterol free, low-fat diet to provide a protein level of 20%. A comparison of serum amino acids in leaf protein-fed vs. casein-fed rats showed that, glycine was the only amino acid having a higher concentration whereas concentration of other amino acids were lower in the leaf protein-fed rats compared with the casein-fed rats. Further alanine was significantly lower in the leaf protein-fed rats compared with the casein-fed rats, and the protein-induced differences in glycine and alanine concentration of unfed rats were reproducible. Concentration of several amino acids, rarticularly valine, leucine and tyrosine, also changed when serum cholesterol concentrations varied, but these effects could not be explained by our experiments. The results suggest that a change in serum concentration of glycine and alanine of unfed rats may be related to the change in serum cholesterol concentration. These data also suggest appear to function in a similar way to soybean protein in their hypocholesterolemic action.

• The Korean Journal of Community Living Science
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• v.16 no.4
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• pp.39-45
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• 2005

The aim of this study is to investigate the effects of hot water soluble extract from green tea on the components of serum and the liver and the antioxidative effects in accordance with the different protein types. For this purpose, four experimental groups were set up. As for the protein source casein, isolated soy protein was supplemented to the rats, together with hot water soluble extract from green tea. Four experimental groups kept eight Sprague-Dawley rats respectively. The CP group was supplemented with casein only, the CG group was supplemented with casein and hot water soluble extract from green tea, the ISP group was supplemented with isolated soy protein only, and the ISG group was supplemented with the isolated soy protein with hot water soluble extract from green tea. After 4 weeks of feeding with experimental diet, the levels of serum and liver lipid and antioxidant enzyme activity and TBARS in the liver were measured. The results are; 1. Weight gain and FER were higher in the casein group than in the isolated soy protein group in general. In the casein group, the weight gain and FER were reduced significantly when hot water soluble extract from green tea was supplemented (P < 0.05). There was no significant difference in feed intake. 2. In general, total cholesterol and LDL-cholesterol in the serum were higher in the casein group than in the isolated soy protein group, however just the concentration of LDL-cholesterol in the casein group was significantly lower when the hot water soluble extract from green tea was supplemented (P < 0.05). 3. Triglycerides in the liver were higher in the casein group than in the isolated soy protein group general, however when hot water soluble extract from green teas was supplemented only in the isolated soy protein group, the content of triglyceride in liver was significantly lower (P < 0.05). 4. There was no significant difference in antioxidant enzyme activity in the liver in all the groups, however the content of TBARS was low only in the casein group when hot water soluble extract from green tea was supplemented (P < 0.05).