• Journal of Dairy Science and Biotechnology
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• 제40권3호
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• pp.134-142
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• 2022

Protein-enriched dairy powder is widely consumed to promote muscle synthesis. Recently, in Korea, elderly people have also begun consuming protein powder products to prevent muscle loss. However, these protein-enriched powders have poor flowability and hydration properties because of the fine particles of spray-dried milk protein powder. Therefore, in this study, the fluidized bed agglomeration process was used to solve these problems. The rheological and physical properties of milk protein isolate (MPI)/skim milk powder (SMP) mixtures were effectively improved via fluidized bed agglomeration. The particle size of the MPI/SMP mixtures significantly increased from 35.7-58 ㎛ to 118-136 ㎛, the flowability level improved from fair (21.4-26.3) to good (15.7-16.3), and the cohesiveness level changed from intermediate (1.27-1.36) to low (1.18-1.19) after fluidized bed agglomeration. In addition, the wetting time of the agglomerated MPI/SMP mixtures was effectively reduced to 4.67-58.3 s by fluidized bed agglomeration. These findings may be useful for manufacturing protein-enriched dairy powders with good instant properties.

• Composites Research
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• 제28권2호
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• pp.40-45
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• 2015

The purpose of the present work was to preparation and study of full biodegradable Eco-friendly bio-composites by using renewable resources. In this study, wheat protein isolate (WPI) films were formed by cross linking with resorcinol through solution casting method for packaging applications. By varying the resorcinol content (10, 20, 30, 40, and 50 wt %), its effect on mechanical properties of the wheat protein isolate film was measured. The addition of 20% resorcinol led to an overall increase in the tensile strength from 5.2 to 18.6 MPa and modulus increase from 780 to 1132 MPa than WPI films. The % elongation was increased from 2.8 to 9.05 when compared to unmodified WPI film. A thermal phase transition of the prepared WPI was assessed by means of DSC. FTIR is evident that the characteristic WPI spectral IR bands shifted on cross-linking with resorcinol.

• Journal of Nutrition and Health
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• 제38권4호
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• pp.279-288
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• 2005

The purpose of this study was to examine whether soybean protein isolate with rich isoflavones which was the same amount as used for earlier study prevents bone induced by ovarian hormone deficiency. Forty female Sprague-Dawley rats (body weight 210 $\pm$ 5 g) were divided into two groups, ovariectomy (OVX) and sham surgery groups, which were each randomly divided into two subgroups that were fed casein and soybean protein isolate with rich isoflavones (isoflavones 3_4 mg/g protein). The diets were fed for 9 weeks after operation. The results of this study indicate that body weight gain and food intake were higher in OVX groups than in SHAM groups regardless of diets. Weight gain were higher in soy isolate groups than in casein groups. Serum Ca concentration was lower in OVX rats than in SHAM rats when fed casein diet. Within the OVX groups, serum Ca concentration was higher in rats fed soy isolate diet than in rats fed casein diet. Serum ALP were higher in OVX groups than in SHAM groups. Within the OVX, soy isolate groups, indices of serum osteocalcin, were a trend for greater than those of the OVX casein group. Crosslink value were increased in ovariectomy groups. Spine BMD and femur BMD of ovariectomy groups were significantly lower than SHAM groups. However, soy isolate with rich isoflavones group in ovariectomy groups, spine BMC and femur BMC were significantly increased after 9 weeks. In conclusion, the soy protein with rich isoflavones was beneficial for bone in ovareiectomized rats and the results were similar to the findings of our previous study which showed a beneficial effect on bone in growing rats.

• 한국식품조리과학회지
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• 제6권3호통권12호
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• pp.9-15
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• 1990

Peanut prptein isolate was tested for the purpose of finding out the effect of pH, Sodium Chloride concentration and heat treatment on the solubility, surface hydrophobicity, foam expansion and foam stability. The solubility of peanut protein isolate was affected by pH and showed the lowest value at pH 4.5. When the peanut protein isolate was heated, the solubility decreased at pH 3 and pH 7 but at pH 9 solubility increased. At all pH range, solubility decreased as NaCl was added. The surface hydrophobicity of peanut protein isolate showed the highest value at pH 1.5. Generally, at acidic pH range the surface hydrophobicity was high, but at alkaline region, the surface hydrophobicity increased as the temperature increased. And when NaCl was added, the surface hydrophobicity was also increased. Foam expansion of peanut protein isolate was no significant difference among the values about pH. When the peanut protein was heated and NaCl was added, foam expansion was increased at pH 7. Foam stability was significantly low at pH 4.5 and foam stability was increased at acidic pH region below pH 4.5. At pH 7 and pH 9, heat treatment above $60^{\circ}C$ increased foam stability. When NaCl was added, foam stability was significantly increased at pH 3 and pH 7.

• 한국식품영양과학회지
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• 제35권9호
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• pp.1251-1255
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• 2006

대두단백 필름을 코팅한 라이너지의 효과를 알아보기 위하여 대두단백 $2\sim8%$의 농도 범위에서 필름을 제조하였다. 필름 제조시 친수성 소재인 대두단백의 불용화를 위하여 모든 필름은 formaldehyde로 포화된 데시케이터에서 2시간 동안 흡착하여 사용하였다. 필름의 연신강도, 연신율, 투습도 및 수분용해도를 측정한 뒤 최적 농도를 5%로 판단하였다. 필름의 제조적성을 위해 첨가된 가소제 glycerol은 대두단백 대비 40% 농도에서 필름제조에 가장 적합하였다. 앞의 조건을 이용하여 제조된 용액을 라이너지에 코팅하여 그 물성과 수분저항성을 측정하였다. Formaldehyde 처리된 대두단백 코팅 라이너지는 미처리 라이너지에 비하여 연신강도는 15 에서 21 MPa로 증가하였고, 수분용해도와 투습계수는 1.17%와 $2.06ng{\cdot}m/m^2{\cdot}s{\cdot}Pa$로 감소하여 물리적 성질과 수분저항성 모두 증진된 것을 알 수 있었다.

• 한국식생활문화학회지
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• 제14권5호
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• pp.467-476
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• 1999

We studied to improve the functional properties of soybean protein isolate by dimethylglutarylation and acetylation. Soybean protein isolate was acylated rapidly up to 80% modification and more of 80% modification was proceed slowly. Electrophoretic analysis showed that more changes in modified protein. Also, modification of soybean protein produced more ionizable tyrosines and exposed more hydrophobic groups, while modified protein exhibited a loss of reactive sulfhydryl groups. Spectrophoretic studies demonstrated that the shift was occurred at the UV 278nm and fluorescence 333nm, respectively, and the intensity decreased as the degree of modification was increased.

• Journal of Nutrition and Health
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• 제36권4호
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• pp.359-367
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• 2003

The purpose of this study was to examine the impact of soy protein and soy isoflavones on bone and mineral density in young female Sprague-Dawley rats. Fifty eight rats (body Weight 75 $\pm$ 5 g) were randomly assigned to one of four groups, consuming casein, soy protein concentrate, soy protein isolate (57 mg isoflavones/100 g diet) or casein added isoflavones (57 mg isoflavones /100 g diet). All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur on 3, 6, 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Diet did not affect weight gain and mean food intake. Food efficiency ratio was lower In soy protein groups. The serum concentration of Ca and P were not changed by soy protein and isoflavones. Urinary Ca and P excretion were not significantly different. Spine BMD was significantly increased by soy protein isolate on 3 and 6 weeks after feeding. Femur BMD was significantly increased in the groups of soy protein isolate and isoflavones adding on after 9 weeks. Therefore, soy protein with rich isoflavones may be beneficial on spine and femur BMD increasement in growing female rats.

• 한국식품조리과학회지
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• 제23권6호
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• pp.810-817
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• 2007

The quality properties of Jeung-pyun made with soybean protein isolate(SPI) were investigated. The SPI Jeung-pyun was manufactured using 3% whole protein, 7S protein or 11S protein(w/w). The redness values (a-values) of the Jeung-pyun were negative and the yellowness(b-value) of the control group was significantly lower compared to the other samples. The textural characteristics of the Jeung-pyun were influenced by the additions of SPI. The Jeung-pyuns containing soybean flour, whole protein, 7S and 11S protein had increases in springiness, but decreases in cohesiveness. In the sensory evaluation, overall desirability, sweetness, and moistness were highest in the whole protein group. The control group showed the highest scores for hardness and toughness, and the scores for after-taste and adhesiveness were the highest in the samples made with soybean flour. The 7S and 11S additions showed high scores in terms of color and springiness. In the analyses for consumer acceptance and sensory quality intensity, the whole protein addition had significantly higher scores for general acceptability and the Makgeolli flavor. Hardness was highest for the control group and the Makgeolli flavor was strongest with the soybean flour addition.

• 한국식품과학회지
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• 제31권6호
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• pp.1488-1494
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• 1999

감마선 조사가 상업적 등급의 SPI와 WPC의 SDS-PAGE 헝태와 이차구조 함량, 용해도 등 이화학적 변화에 미치는 영향을 조사하였다. 감마선이 조사된 SPI와 WPC의 SDS-PAGE 형태은 SPI 용액의 경우 5 kGy 이상 조사에서 단백질의 degraded pattern과 아울러 중합이 나타난 반면에 WPC 용액에서는 단백질이 절단된 형태로 나타났다. 반면에 감마선이 조사된 SPI와 WPC 분말의 경우 분자량 분포에는 큰 변화가 없었다. Circular dichroism 연구에서 감마선이 조사된 SPI와 WPC용액의 이차구조의 변화는 감마선 조사에 의하여 단백질의 구조 변화를 나타내는 random coil함량이 증가하였다. 또한, SPI와 WPC 분말의 경우에는 감마선 조사에 의한 용해도의 차이가 있었다.

• The Plant Pathology Journal
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• 제20권2호
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• pp.155-157
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• 2004

We isolated Rice dwarf virus (RDV) from infected plants in rice fields (Korea, Japan, China, the Philippines and Nepal) and analyzed their genomic dsRNAs by polyacrylamide gel eletrophoresis. The genomic dsRNAs of the isolates showed distinct electrophoretic mobility profiles. The S12 coding to nonstructural protein of Korean isolate (RDV-Kr) was further analyzed by sequencing. The S12 of RDV-Kr was 1,066bp long and coded for a protein composed of 312 amino acids including three open reading frames of P12, P120Pa and P120Pb. The sequence identities were 96% and 98.6% with Japanese isolates (H, AN), 94.7% with Nepalese isolate (NEL), 94% with Chinese isolate (CK) and the Philippines isolate (P).