• 한국식품영양학회지
• /
• 제27권1호
• /
• pp.89-98
• /
• 2014

In this study, soybean is used to produce soymilk according to various extracting methods and heating time. Specifically, the soy slurry is being filtered before being heated, or heated before being filtered. Following that the soymilk produced is freeze-dried to be powdered, and then, the quality characteristics of the powdered soymilk are mutually compared to determine the applicability of various food additives. The freeze-dried soymilk powder shows 2.03~6.35% of moisture content, and in terms of unit quantity, retained more proteins, which suggests that the ratio of protein extraction is higher than any other nutrients. Accordingly, the protein coefficient is significantly higher in soymilk powder being heated and processed than in raw soybeans. In particular, protein coefficient is the highest in the soymilk which is heated for 20 minutes before being filtered (SHBF20). The longer the heating time was, the trypsin inhibitor (TI) tended to be far less active. Such an inactivation seems to be more apparent in the "SHAF" soymilk powder than "SHBF" soymilk powder. Because protein had to be denaturated by heating for soymilk, the nitrogen solubility index (NSI) of soymilk powder is decreased considerably, while the protein digestibility, water absorption, emulsification and foaming activity all increase. Oil absorption tends to decrease slightly. As discussed above, the soymilk heated for 10 minutes after being filtered (SHAF10) and the soymilk heated for 20 minutes before being filtered (SHBF20) show optimum processing conditions for soymilk powder.

• Journal of Nutrition and Health
• /
• 제28권10호
• /
• pp.986-994
• /
• 1995

This study was to examine the effect of phytate on the protein digestibility and calcium, iron and zinc availability in phytase treated soymilks digested with pepsin and pepsin-pancreatin in vitro. Also, the bending between phytate and protein in soymilks was investigated by means of SDS-PAGE. The content of phytate in soymilk was reduced by phytase treatment. As the content of phytate decreased, the protein digestibility increased in soymilk treated with the digest enzymes in vitro. The reduction of phytate content in soymilk improved the availability of all calcium, iron and zinc. Although the availability of calcium increased, the amount of change was small. The phytate reduction increased most the availability of iron. A number of bands of high molecular weight protein in soymilk disappleared in SDS-PAGE by lowering the phytate content with phytase treatement on soymilk.

• 한국식품저장유통학회지
• /
• 제15권6호
• /
• pp.903-908
• /
• 2008

본 연구는 두유와 전두유의 효소적 가수분해에 따른 단백질의 변화를 조사하였다. 총 유리아미노산 함량을 조사한 결과 두유(SM)과 전두유(WSM)에 비해서 저분자 두유(LSM)와 저분자 전두유(LWSM)에서 높게 나타났다. 필수아미노산 함량은 SM과 LSM에서 비슷하였으나 LWSM은 WSM보다 높게 나타났다. SDS-PAGE 전기영동 패턴 분석결과 SM과 WSM에서는 $33{\sim}72\;kDa$의 고분자가 존재하였으나 LSM와 LWSM에서는 17 kDa 이하의 저분자 단백질만 나타났다. 또한 이차원 전기영동한 결과 SM과 LSM에서의 고분자 단백질 spot이 WSM와 LWSM에서는 다양한 크기의 저분자 단백질 spot으로 변환되어 효소가수분해에 의해 고분자 단백질이 저분자화 되는 것으로 나타났으며, 향후 단백질 spot의 분리 및 특성에 관한 연구가 필요하다.

• Applied Biological Chemistry
• /
• 제35권6호
• /
• pp.501-506
• /
• 1992

두유박 단백질을 시료로 하여 pepsin을 사용한 가수분해와 plastein 합성의 최적조건을 조사하였다. 가수분해의 최적 기질농도는 3%이었으며, 기질에 대한 최적의 효소 농도는 2%이었고, 최적 pH, 반응온도 및 반응시간은 각각 pH 1.7, $45^{\circ}C$ 및 24시간이었다. Plastein 합성 조건으로 기질농도 40%, pH 4.0, 반응온도 $45^{\circ}C$, 반응시간 18시간, (효소/기질) 농도 1%를 설정하였다. 생성된 plastein은 반응시간 및 기질농도 별로 전기영동으로 확인하였다.

• 한국식품영양학회지
• /
• 제19권4호
• /
• pp.381-391
• /
• 2006

The rheological properties of dough made the substitution of wheat flour(composite flour) at the levels of 0%, 5%, 10% and 15% soymilk residue flour, with addition of vital wheat gluten at the levels of 3, 6 and 9% were investigated. And nutrition contents of soymilk residue flour were analyzed. The results were as follows; Principal components of soymilk residue flour were 22.0% crude protein, 13.2% crude lipid, 54.3% carbohydrate, 27.2% dietary fiber and $220{\mu}g/g$ isoflavones. Free amino acid component of soymilk residue were L-glutamic acid, L-leucine, L-lysine, L-valine, L-phenylalanine, L-isoleucine, L-threonine, L-methionine and L-cystine. Total dietary fiber content of bread with soymilk residue and wheat flour were 5% soymilk residue; 3.50%, 10% soymilk residues; 4.65%, 15% soymilk residues; 5.96%, and wheat flour bread: 2.1% respectively Mixing water absorption capacity was increased by increasing amounts of added soymilk residue and vital wheat gluten. Dough development time was increased by increasing amounts of added soymilk residues, while decreased by increasing amounts of vital wheat gluten. The dough volume of composite flour with 5%, 10% and 15% soymilk residue flour were the smaller than wheat flour dough. But the dough volume was increased by added vital wheat gluten, and the composite flour with 5% soymilk residue flour and 9% vital wheat gluten was better than the others. This study proved that the dough volume of composite flour with 5% soymilk residue flour and 9% vital wheat gluten was better than the others. On the other hand, the soymilk residue flour contains dietary fiber, isoflavone, protein, lipid and carbohydrate. Therefore the soymilk residue flour will be very useful as food material.

• 한국식품영양학회지
• /
• 제15권4호
• /
• pp.331-336
• /
• 2002

본 연구는 두유에 칼슘을 강화하고자 두유단백질의 칼슘내인성을 높이기 위한 방법으로 단백분해효소를 처리한 경우 효소처리 전, 후에 나타나는 단백질의 구조적 특성을 비교 분석하였다. 표면소수도는 SMP

• 한국식품영양학회지
• /
• 제14권6호
• /
• pp.562-567
• /
• 2001

In order to utilize okara protein as a food auditive, nutritional composition of soymilk okara was investigated. Protein in okara Is highly insoluble due to excessive heat treatment during soymilk processing. Protein content of okara was 37.3% as compared to 42.5 % for soybean. Carbohydrate and lipid contents of okara were 40.6% and 17.9%, respectively. Okara lipid extracted with chloroform-methanol consisted of neutral lipid, glycolipid and phospholipid, with neutral lipid making up 98.6% . Linoleic acid, ileic acid, and palmitic acids accounted for about 80% of the total fatty acids with linoleic acid sharing 50.3% of the total. Amino acid composition of okara protein was dissimilar to that of soy Protein : Cysteine was totally absent in okara while lysine, which is the limiting amino acid of soy protein, was present in higher amount in okara on dry weight basis. Both aqueous extract of okara protein and soy Protein were found to have ACE inhibitory activity.

• 한국식품영양학회지
• /
• 제7권4호
• /
• pp.345-352
• /
• 1994

High protein beverage of cow-soy milk was prepared by mixing the soymilk and commercial homogenized cow milk in the various ratios. Effect of heat treatment, pH and addition of calcium and sucrose was studied on the water-soluble nitrogen of cow-soy milk The heat-treated soymilk at 10$0^{\circ}C$ were centrifuged at the range of 830~29,900xg for 30 min and 11,200xg was found to be proper for determination of the degree of protein denaturation by centrifugal method. When soymilk was heated at 70~10$0^{\circ}C$ for 30~240 min, soluble nitrogen (QA SN) in supernatant of protein was decreased to 78.0~56.8% due to protein denaturation. Most of heat denaturation of protein was found to be occurred during Initial heating 10$0^{\circ}C$ for all mixed cow-soy milk. The sedimentation of SN was maximum at pH 4.0 In the range of pH 3~8. Addition of sucrose affected little on oASN while calcium addition reduced %SN significantly to approx. 55% for soymilk(100%). The effect of Ca was less as the ratio of cow milk increased.

• 한국식품과학회지
• /
• 제28권6호
• /
• pp.995-1000
• /
• 1996

본 실험은 두유에 칼슘을 강화하기 위해 두유 단백질의 칼슘내인성을 높이기 위한 방법으로 두유 단백질을 부분가수분해시킬 최적 단백분해효소 및 그의 최적 처리조건을 결정하였고, 효소처리한 뒤 칼슘염을 첨가하여 제조된 칼슘강화 두유의 체외소화시 단백질과 칼슘의 소화특성을 조사하였다. 두유에 처리된 4가지 단백분해효소 중에서 Bacillus polymyxa의 단백분해효소가 pH 7.5, $50^{\circ}C$, 10min의 처리조건하에서 처리 후 두유에 쓴맛을 남기지 않고, 칼슘염을 첨가하였을 때 응고현상을 가장 적게 나타내는 것으로 밝혀졌다. 또 가수분해 정도가 증가할수록 칼슘에 의한 응고정도는 감소했으나 10분 이후부터는 쓴맛이 감지되었으므로 효소처리시간은 10분으로 결정하였다. 두유에 효소처리를 한 뒤 염화칼슘을 5, 15, 25 mM 첨가하여 칼슘강화 두유를 제조하여 단백질의 체외소화율을 분석한 결과, 두유에 첨가된 칼슘의 농도와 무관하게 모든 칼슘강화 두유가 표준두유와 유사한 소화율을 나타냈다. 소화전에는 표준두유에 비해 효소처리만 한 두유의 가용성 칼슘이 약간 높으면서 이온형태의 것은 적게 나타났으며 효소처리 후 염화칼슘을 5, 15, 25 mM 첨가하여 만든 칼슘강화 두유는 이온형태의 칼슘함량이 점차 증가하였다. 펩신을 처리하였을 때는 가용성칼슘이 거의 이온형태의 것으로 나타났으며 두유에 칼슘이 많이 강화될수록 유리되는 이온형태의 칼슘함량도 증가하였다. 이상의 결과를 미루어 볼 때, 우유와 비슷한 수준으로 칼슘이 첨가된 두유도 단백질의 체외 소화율은 감소되지 않았으며, 소화시 체내에 흡수될 수 있는 이온 형태의 칼슘의 양은 첨가량과 비례하였으므로 이와 같은 방법으로 칼슘강화 두유를 제조할 때 칼슘의 체내 이용도는 증가할 수 있을 것으로 생각된다.

• Journal of Dairy Science and Biotechnology
• /
• 제30권2호
• /
• pp.83-92
• /
• 2012

This study was performed for analyzing the general composition and the change in the quality of soymilk-derived yogurts manufactured by adding skim milk and whey powder to soymilk heat-treated at $95^{\circ}C$/5 min and $120^{\circ}C$/10 min, respectively. 1. During the storage of soymilk yogurt, the concentrations of total solids, protein, fat, and lactose slightly decreased, whereas viscosity, content of ash and NPN, and the number of lactic acid bacteria remained unchanged. 2. The pH and titratable acidity changed rapidly in all soymilk yogurts after 3 h of incubation. 3. We found $7.8{\times}10^8$ lactic acid bacteria in the control sample, $4.7{\times}10^8$ and $5.02{\times}10^8$ in soymilk yogurt with skim milk, respectively, and $5.9{\times}10^8$ and $5.5{\times}10^8$, respectively in soymilk yogurt with whey powder according to degree of heat treatment with $95^{\circ}C$/5 min and $120^{\circ}C$/10 min. 4. The viscosity of yogurt samples became lower as the heat treatment increased in temperature and in the length of time. 5. The value of sensory evaluation was relatively high in soymilk yogurt with the added skim milk, which was heat-treated $95^{\circ}C$/5 min; however, the value was significantly lower than that of the control sample. 6. Lactose, glucose, and galactose were detected in all samples because lactose is degraded into glucose and galactose within 3 h of inoculation.