• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.428-436
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• 2008

This study was carried out to compare the effects of whey protein concentrate, its hydrolysates and macropeptide fractions obtained from papain treatment of whey protein on lipid levels and appetite-related hormones in obesity model rats induced by high fat diet. Four week-old male Sprague-Dawley rats were fed high fat (18% w/w) and low protein (10% w/w) diet for 4 weeks and then divided into four groups (n=8/group). Rats were fed high fat diets containing various nitrogen sources; 10% whey protein concentrate (10WPC), 25% whey protein concentrate (25WPC), 25% whey protein hydrolysates (25WH), and 25% whey macropeptide fractions (25WP, MW$\geq$10,000), respectively for 6 weeks. There were no significant differences in body weight gain and food intake among groups. A significant decrease of total lipid, triglyceride in serum was observed in 25WH and 25WP groups. Total lipid and triglyceride contents of the liver were significantly decreased in 25WPC, 25WH and 25WP groups compared with 10WPC group. However, in the liver, there were no differences in the contents of total lipid and triglyceride among 25WPC, 25WH and 25WP groups. The daily amounts of feces were significantly increased in 25WH and 25WP groups and the excretion of total lipid and triglyceride were significantly increased in 25WH group. Serum glucose and insulin concentration were significantly decreased in 25WH group. The concentration of serum ghrelin was significantly decreased in the 25WPC, 25WH and 25WP groups compared with 10WPC group. However, there was no significant difference in the concentration of serum leptin among groups. These results suggest that whey protein hydrolysates and macropeptide fractions may show beneficial effects on the lipid profile in serum and liver, appetite regulation and insulin resistance in obesity model rats induced by high fat diet.

• 베이커리
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• no.9 s.362
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• pp.76-81
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• 1998

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.537-542
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• 2019

Proteins were isolated from four species of edible insects, Bombyx mori, B; Tenebrio molitor, T; Protaetia brevitarsis, P; and Gryllus bimaculatus, G, and their properties were analyzed and compared with those of whey proteins. The yield of the protein isolated from raw materials was 65.0-75.0%. Among three branched chain amino acids (BCAA), the amounts of valine in all the insects were similar to that of the whey protein. The BCAA content was 16.8 and 16.4% in G and T, respectively. The total polyphenolic content and the antioxidant activity of the insect proteins were significantly higher than those of the whey proteins. Based on the sensory test of the protein powder, the whey protein could be replaced by 25% of the isolated protein from the insects, but the taste and flavor needs to be improved. Although the BCAA content of insect proteins was lower than that of the whey protein (by 73-76%), their application could be useful because of high polyphenolic content and the anti-oxidative activity.

• Bulletin of Food Technology
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• v.9 no.2
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• pp.133-139
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• 1996

최근 6할이상의 주부들이 가공식품 혹은 반가공식품을 이용하고 있으며 그 이유는 이용의 간편성, 조리가 간단하고 합리지향적인 구매행위가 가능한 점으로 꼽을 수 있다. 특히, 일본의 경우 노년인구층의 급증으로 인한 부드러운 식품소재의 이용성이 크게 늘어나고 있는 추세에서, 강하지않고 부드러운 향미 및 질감, 먹기쉬운 간편성등과 영양기능성이 강조된 제품개발이 활발히 이루어지고 있다. 따라서, 가공식품을 개발하려는 목적위에 소비자의 연령층에 대응하고, 보다 고도의 기능특성(영양성, 안전성, 경제성등)을 결합시킨 개념들이 도입되고 있다. 단백질은 가공식품의 물성을 결정하는 성분으로써 우유, 계란, 대두 및 밀가루단백질들을 이용하여 물성개량을 위한 잠정적 식품첨가물로 이용가치가 높다. 주로 구상단백질로 구성이 되어 있는 우유의 유청단백질을 특수한 처리에 의해 가용성 선상응집체(Soluble linear aggregate)로 가공한 유청단백질(Process whey protein)은 원래의 미변성 유청단백질에 비해 증강된 기능특성(표 1)을 지니고 있다. 지난 10년간 유청의 유용성에 대한 인식이 증가된 것은 물론 막기술이나, 이온 교환기술을 이용한 유청가공기술이 점진적으로 발달해왔다. 유청의 원재료는 물론이고 가공적성을 이해함으로써, 산 안전성, 겔화, 막형성, 기포형성, 유화액형성 등의 수많은 식품학적 기능특성들이 제고될 수 있다. 따라서, 식품에 응용될 수 있는 이들 기능특성들을 다듬어, 유청단백질을 특별한 목적용 제품으로 개발할 수 있도록 넓은 범위의 정보를 제공하는 것이 중요하다. 이에 유청단백질의 제조 및 가공을 제고하고, 식품에 광범위하게 응용할 수 있는 유청단백질의 다양한 식품학적 기능특성을 논의하고자 한다.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.339-345
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• 2012

This experiment was carried out in order to separate bovine colostral whey protein from Imsil province and to test the effect of immunological activity on RAW 264.7 cells. The colostral whey protein contained TGF-${\beta}$ 7, 475 pg/g in total. We first tested the effect of the colostral whey protein on the proliferation of RAW 264.7 cells and it demonstrated cytotoxicity at concentrations greater than 20 mg/mL. Therefore, the immunological activities of colostral whey protein were investigated in maximum concentration of 10 mg/mL on LPS-induced RAW 264.7 cells. Results indicated that colostral whey protein inhibited the LPS-induced nitric oxide (NO) production in a dose-dependent manner. The colostral whey protein also suppressed the productions of proinflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$, IL-6) in a dose-dependent manner. In addition to the immunological activity, colostral whey protein led to the expression of heme oxygenase-1 (HO-1) in RAW 264.7 cells. In conclusion, colostral whey protein containing TGF-${\beta}$ inhibited the production of NO, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 via expression of HO-1.

• 축산식품과학과 산업
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• v.7 no.2
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• pp.10-17
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• 2018

• Applied Biological Chemistry
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• v.29 no.1
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• pp.83-89
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• 1986

To investigate effectors on the colloidal stability of whey and soybean proteins, characteristics of tofu-gel formation, effects of heat treatment and salt composition on the colloidal stability, and effects of heat treatment on storage stability were analyzed. When experimental tofus were made from the mixture of whey and soybean, the calcium in the whey precipitated the soy proteins, and disrupted the gel formation, which resulted in the curd of poor texture. In the heat treatment at $60{\sim}100^{\circ}C$, whey and the whey proteins dialyzed against distilled water were readily preciptated at over $70^{\circ}C$, but the mixture of whey and soy extract as well as soy extract were stable at the range of temperature. The proteins of soy extract, whey dialyzed against sodium phosphate buffer, and the mixture were stable at the same heat treatment, and this suggested that phosphates in the soy extract stabilize specialty the whey proteins. Soy proteins were easily destabilized by adding $CaCl_2(0.05{\sim}0.07M)$ at $80{\circ}C$ and $70{\sim}85%$ of the proteins in soy extract and the mixture were preciptated, while only $30{\sim}55%$ of the proteins in whey dialyzed against distilled water were destabilized at the same conditions. Storage stability at $4^{\circ}C$ of the mixture was increased when the mixture was treated at $63^{\circ}C$ and lower temperature.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.161-164
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• 1993

To find out the effective indicators for identification and classification of different heat treatment, the contents of nitrogen fractions and the degrees of whey protein denaturation in market milks were investigated by Kjeldahl method. The contents of nitrogen fractions per 100ml raw milk were total nitrogen (431.3mg), casein nitrogen (341.0mg) and non-casein nitrogen(90.3mg), in which non-protein nitrogen (31.6mg) and denatured whey protein nitrogen (58.8mg), while those of LTLT, HTST, UHT pasteurized and UHT sterilized showed different values. The degrees of whey protein denaturation were 26.7%(LTLT), 32.9%(HTST), 60.7%(UHT pasteurized) and 38.4%(UHT sterilized), respectively. As the higher temperature was applied for the treatment of milk, the degree of the whey protein denaturation was higher. Remarkable differences in the degree of whey protein denaturation according to the heating methods were observed.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.304-308
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• 2006

This study was performed to understand the behavior of protein mobility and intensity of enzymatic hydrolysis according to crosslinking of sodium caseinate, whey protein isolate, skim milk and whole milk powders with or without transglutaminase (TGase, w/w = 200 : 1) at $38^{\circ}C$. Whey protein was limited to crosslinking and skim milk was relatively more increased in high molecular polymer than whole milk. The degree of crosslinking decreased in the order of sodium caseinate>skim milk>whole milk>whey protein isolate. The SDS-PAGE results indicated that main bands of TGase treated samples had a high mobility and formed bands of molecular weights below 15 kDa by hydrolysis with pepsin after 10 min of reaction time. However, ${\beta}-lactoglobulin$ showed remarkable stability against pepsin hydrolysis treated with and without TGase. The high molecular polymers were easily hydrolyzed with digestive enzymes in vitro experiment. These results suggested that novel dairy products using TGase would have no special digestive problem in human body.