• Food Science and Biotechnology
• /
• 제15권6호
• /
• pp.860-865
• /
• 2006

The quality parameters of sponge cake supplemented with soy protein concentrate (SPC) were evaluated. The addition of SPC to wheat flour increased the protein content and alkaline water retention value, but decreased the sedimentation value. Protein content had a positive correlation with the alkaline water retention value, and a negative correlation with the sedintentation value. The higher the concentration of SPC, the higher the RVA pasting temperature and the lower the viscosity. Increasing the level of SPC in flour led to a decrease in mixogram peak time, whereas peak height, width at peak, and width at 8 min progressively increased. As the amount of SPC increased in the formulation, the pH and specific gravity of cake batter increased, whereas the volume and specific volume of sponge cake decreased. The total isoflavones content in SPC increased after heat treatment. The hardness, gumminess, and chewiness increased progressively in accordance with increasing level of SPC.

• Journal of Nutrition and Health
• /
• 제36권5호
• /
• pp.452-458
• /
• 2003

Soybean is a rich source of isoflavones such as genistein and daidzein. Soy isoflavones have both weak estrogenic and anti-estrogenic effects and are structurally similar to tamoxifen, an agent that has an effect similar to that of estrogen in terms of reducing postmenopausal bone loss. The purpose of this study was to determine the effects of differences in protein source (casein vs soy) and isoflavone levels (reduced vs higher levels) on selected bone markers and hormones in growing male rats. Thirty weanling Sprague-Dawley young rats were divided into 3 groups: The control group was fed a casein-based diet, the soy concentrate group was fed soy protein with totally reduced isoflavones content (isoflavones 0.07 mg/g protein), and the soy isolate group was fed soy protein with a higher than normal isoflavones content (isoflavones 3.4 mg/g protein). The degree of bone formation was estimated by measuring serum osteocalcin and alkaline phosphoatase (ALP). By determining collagen cross-linkage by immunoassay and correcting with creatinine values, the bone resorption rate was compared. Serum osteocalcin, growth hormone, estrogen and calcitonin were analyzed using radio immunoassay kits. The bone formation marker and ALP activity were differentiated by protein source, showing higher values than casein in feeding either soy isolate or soy concentrate. In this study using growing rats, the differences in isoflavone contents were not a significant factor in either bone formation or bone reaborption markers. Moreover, the soy isolate group had significantly higher levels of growth hormone than the casein group. The findings of this study suggest that growth hormone is partially responsible for its bone-formation effects in young growing rats. Soy protein and the isoflavones in soy protein are beneficial for bone-formation in growing male rats. Therefore, exposure to soy protein and isoflavones early in life may have long-term health benefits in preventing bone diseases such as osteoporosis. Further study to evaluate the mechanism of action of isoflavones on bones is warranted. (Korean J Nutrition 36(5): 452∼458, 2003)

• 한국수산과학회지
• /
• 제54권1호
• /
• pp.118-123
• /
• 2021

This study was conducted to evaluate plant proteins as a replacement for a fishmeal diet in the rearing of coho salmon Oncorhynchus kisutch. Twelve groups of 20 fish averaging 34.0±0.62 g were randomly distributed into 12 rectangular tanks (250 L). Four experimental diets included a control diet containing 60% fishmeal (Control), and three other diets that replaced 20% of fishmeal with soy protein concentrate (SPC), fermented soybean protein concentrate (F-SPC), and enzyme-processed soy protein concentrate (E-SPC). At the end of the feeding trial, fish that were fed Control, SPC and E-SPC diets showed significantly higher weight gain, specific growth rate, feed efficiency, and protein efficiency ratio than those that were fed F-SPC diet. However, there were no significant differences among the fish that were fed Control, SPC, and E-SPC diets. No significant differences were observed in crude protein, crude lipid, and ash of whole body among the fish that were fed all the diets. Therefore, these results indicated that 20% of fishmeal could be replaced by E-SPC or SPC without any adverse effects on the growth performance of coho salmon.

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

• Journal of Nutrition and Health
• /
• 제35권4호
• /
• pp.409-413
• /
• 2002

성장기 수컷 흰쥐를 대상으로 콩단백질과 콩의 isoflavones의 함량이 골밀도 및 골함량에 미치는 효과를 알아본 결과는 아래와 같다. 1) 식이 효율은 대조군인 casein군에 비하여 콩단백질군이 낮았다. 2) 단백질의 종류나 isoflavones의 유무에 따른 혈 중이나 뇨 중 Ca과 P의 함량에는 유의적인 차이가 없었다. 3) 체중 당 총골밀도는 두 군의 콩단백질군이 대조군 보다 높았고, 콩단백질 내에서는 isoflavones를 함유한 군이 더 높았다. 4) 체중 당 spine의 골밀도나 골함량은 두 군의 콩단백질군이 대조군 보다 높았고, 콩단백질 내에서는 골밀도는 isoflavones를 함유한 군이 유의적으로 더 높았다. 5) 체중 당 femur의 골밀도는 콩단백질군이 대조군 보다 높았고, 콩단백질 내에서는 isoflavones를 함유한 군이 더 높았으나 통계적 유의성은 없었다. 결론적으로 콩단백질은 체중당 총골함량이나 칼슘함량에 있어서 동물성 단백질인 casein 보다 유익하였고 특히 isoflavones를 함유한 콩단백질은 체중당 총골밀도와 spine 골밀도에서 isoflavones 함량이 낮은 콩단백질에 비하여 더 유익하여 콩단백질과 isoflavones은 성장기 수컷 흰쥐에서 골밀도 향상에 유익함을 확인하였다. 따라서 성장기에 콩의 섭취는 casein 단백질에 비하여 골밀도나 골함량을 높이는데 유익하며 특히 isoflavones를 함유한 콩의 섭취는 골밀도를 높이는데 더욱 유익하다고 사료된다.

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

• 한국식품과학회지
• /
• 제21권1호
• /
• pp.92-99
• /
• 1989

본 연구에서는 농축대두단백으로 두유를 만들고 protease를 이용하여 대두단백질을 여러가지 정도로 가수분해한 후, 단백질이 일부 가수분해된 두유에서 L. acidophilus 또는 L. bulgaricus의 생육과 산생성을 관찰하고 제조된 대두 젖산균음료의 관능성을 조사하였다. protease 처리에 의하여 젖산균에 의한 산생성이 촉진되었는데 특히 L. acidophilus에 의한 산생성이 현저하게 촉진되었다. 그러나 pH와 생균수는 큰 변화가 없었다. 15분 가수분해 시료에서 이미 산도가 상당히 증가하였으며 그 후 3시간이 경과하여도 산도의 변화가 현저하지 않았다. 0.1% protease 처리로 대두젖산균음료의 전체적인 기호도가 다소 개선되었다. protease 처리 15분에 비단백태 질소의 함량이 상당히 증가하였고 2시간에 최대치에 도달하였다.

• Journal of Nutrition and Health
• /
• 제36권6호
• /
• pp.549-558
• /
• 2003

The purpose of this study was to determine which differences in the source of protein (soy vs casein) and isoflavones in soy protein are responsible for the differential effects of bone marks and hormones in growing female rats. Forty-two 21-day-old Sprague-Dawley female rats were randomly assigned to one of three groups, consuming casein (control group), soy protein isolate (57 mg isoflavones/100 g diet), or soy protein concentrate (about 1.2 mg isoflavones/100 g diet). All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. And bone resorption rate was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, estrogen and calcitonin were analyzed using radioimmunoassay kits. Diet did not affect weight gain and mean food intake. Food efficiency ratio was lower in the soy protein groups. The soy isolate group had a higher ALP and osteocalcin concentration and lower crosslinks value than the casein group. Therefore, the soy isolate groups had a higher bone formation/resorption ratio than the casein group. And, the soy group had significantly higher growth hormone than the casein group. The findings of this study suggest that soy protein and isoflavones are beneficial for bone formation in growing female rats. Therefore, exposure to these soy protein and isoflavones early in life may have benefits for osteoporosis prevention.

• 한국식품영양과학회지
• /
• 제14권1호
• /
• pp.51-56
• /
• 1985

옛 부터 부수게 제조시 대두 slurry를 첨가하여온 의미와 최적 대두 첨가 형태 및 최적 첨가량을 규명하고자 대두 제품인 대두 slurry, soy protein isolate, soy protein concentrate, defatted soy flour, soy hot water extract를 첨가하여 부수게 바탕에 미치는 결과를 조사한 바 다음과 같이 요약 할 수 있다. 부수게 바탕은 저수분 ($4{\sim}5%$), 고지방($20{\sim}21%$)식품으로 대두 slurry를 첨가함으로써 단백질 강화와 품질 향상에 효과가 있으며 대두 제품중에서 대두 slurry는 용적 증가율, 경도, panel score에서 유리하였고 soy protein isolate는 단백질 강화를 위해서 가장 유리한 형태 이었다. 또한 이상적인 첨가 형태는 대두 slurry와 soy protein isolate를 병용하는 것이었고 이 경우 soy protein isolate의 첨가량은 10% 전후가 적당 하였다.

• Fibers and Polymers
• /
• 제7권4호
• /
• pp.380-388
• /
• 2006

Fully biodegradable and environment-friendly green composite specimens were made using ramie fibers and soy protein concentrate (SPC) resin. SPC was used as continuous phase resin in green composites. The SPC resin was plasticized with glycerin. Precuring and curing processes for the resin were optimized to obtain required mechanical properties. Unidirectional green composites were prepared by combining 65% (on weight basis) ramie fibers and SPC resin. The tensile strength and Young's modulus of these composites were significantly higher compared to those of pure SPC resin. Tensile and flexural properties of the composite in the longitudinal direction were moderate and found to be significantly higher than those of three common wood varieties. In the transverse direction, however, their properties were comparable with those of wood specimens. Scanning electron microscope (SEM) micrographs of the tensile fracture surfaces of the green composite indicated good interfacial bonding between ramie fibers and SPC resin. Theoretical values for tensile strength and Young's modulus, calculated using simple rule of mixture were higher than the experimentally obtained values. The main reasons for this discrepancy are loss of fiber alignment, voids and fiber compression due to resin shrinking during curing.