• 한국식품조리과학회지
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• 제20권3호
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• pp.256-264
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• 2004

The effects of irradiation on the functional and structural characteristics of soy protein isolates were studied. Soymilk was irradiated at 1, 5, and l0kGy, after which soy protein isolates were prepared. The functional properties of soy protein isolates were examined including solubility, emulsion capacity and stability, foam capacity and stability, structural properties as represented by SDS-PAGE pattern, and secondary and tertiary structures. The solubility and emulsion capacity were increased by radiation treatment at 1kGy however the values were adversely affected again as dosage was increased above 5kGy. As irradiation dosage increased, an increase of foaming capacity at 1kGy and a decreasing turnover afterwards were also noted in foaming capacity, although the differences were not statistically significant. The SDS-PAGE pattern showed fragmentation and aggregation of protein molecules as affected by irradiation in proportion to the dosage increase. The results of CD and fluorescence spectroscopy revealed increased aperiodic structure contents with the dosage increase. It was assumed that irradiation dosagefrom 5 to l0kGy could initiate minimal denaturation of protein in various foods compared to general heat treatment.

• 한국식품과학회지
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• 제9권3호
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• pp.190-193
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• 1977

동방유량(東邦油糧)에서 저변성탈지대두박(低變性脫脂大豆粕)을 공급받아 Soy Protein Isolates(SPI)를 제조(製造)하여 이의 식품학적(食品學的) 특성(特性)을 연구(硏究)한바 있다(Korean J. Food Sci., 9, 123(1977)). 이 SPI의 실제응용성(實際應用性)을 검토(檢討)하고자 12% SPI액(液)을 가열(加熱) gel화(化)시켜 풍건 마쇄한 SPI를 beef patties의 증량제(增量劑)로 사용하였을 때, SPI gel로 30% meat를 대체하여도 관능검사(官能檢査) 결과(結果) 유의성(有意性) 있는 차이(差異)를 나타내지 않았다. 또한 cooking loss도 13.5%(대조구(對照區))에서 2%로 현저히 줄었다. SPI를 milk-Solid-Not-fat(MSNF)와 대체하여 제조한 아이스크림은 관능검사결과(官能檢査結果) texture는 대조구(對照區)과 차이(差異)가 없었으나 향미면(香味面)에서 콩비린내 때문에 전체적(全體的) 품질(品質)이 크게 떨어졌다. 이것은 아이스크림이 향미(香味)가 전체품질(全體品質)에 큰영향을 갖는 그 자체의 특성때문인 것으로 간주된다. 탈지대두박(脫脂大豆粕)에서 추출(抽出)한 분리대두단백(分離大豆蛋白)은 콩비린내 문제만 해결(解決)되면 우수한 식품학적(食品學的) 특성(特性)때문에 동물성(動物性) 단백질(蛋白質)과 대체하여 식품제조시(食品製造時) 첨가제(添加劑)로서 사용이 가능(可能)함을 알았다.

• 한국식품조리과학회지
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• 제20권6호
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• pp.658-666
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• 2004

In order to develop and commercialize high quality frozen soy yogurt, the effects of industrial proteases and commercial mixed cultures were examined on the functional properties and the sensory attributes of frozen soy yogurt. For quality improvement, soy protein isolates were primarily hydrolyzed by either Flavourzyme or Neurtrase, industrial Proteases, to reduce the beany flavor and increase the functional properties of the protein. The viable cell count of lactic acid bacteria was higher in the soy protein hydrolysates than whenuntreated. ABT-5 (L. acidophilus, Bifidobacterium lactis, and S. thermophilus) resulted in higher acid tolerance, bile acid tolerance and melt-down percent values than those with YC-X11 (Lactobacillus bulgaricus and Streptococci thermophilus). The overrun of frozen soy yogurt was improved by both Flavourzyme $(193.3\%)$ and Neurtrase $(156.7\%)$ treatments. With regard to thesensory characteristics, Flavourzyme improved the beany flavor, astringency taste, mouth feel and overall quality of frozen soy yogurts fermented with ABT-5. Further studies onproduct formulation will be needed to commercialize the frozen soy yogurt for the market.

• 한국작물학회지
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• 제51권2호
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• pp.148-153
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• 2006

Effects of ${\alpha}$-chymotrypsin modification on degree of hydrolysis (DH), solubility, emulsifying capacity and thermal aggregation of laboratory-purified soy protein isolate (SPI) using a lipoxygenase-defected soybean (Jinpum-kong) and commercial soy protein isolate (Supro 500E) were compared. SPIs were hydrolyzed by ${\alpha}$-chymotrypsin at pH 7.8 and $37^{\circ}C$ for 30 min. DHs of Supro 500E and Jinpum-kong SPI were increased by ${\alpha}$-chymotrypsin modification, and DH of Supro 500E was higher than that of Jinpum-kong SPI. DH of ${\alpha}$-chymotrypsin treated Jinpum-kong SPI was similar with untreated Supro 500E and DH of treated Supro 500E was the highest. Solubility, emulsifying capacity and thermal aggregation of SPIs were increased by ${\alpha}$-chymotrypsin modification, and these changes were highly related to changes in DH. Functional properties of Supro 500E were higher than Jinpum-kong SPI in both of untreated and ${\alpha}$-chymotrypsin treated SPIs.

• 한국식품조리과학회지
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• 제21권2호
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• pp.217-224
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• 2005

The storage characteristics of frozen soy yogurt prepared with hydrolyzed soy protein isolates were evaluated. In order to facilitate lactic fermentation bacteria grow and produce lactic acid as fast rate as possible, soy protein isolate(SPI) was hydrolyzed using two kinds of proteases; bromelain and a-chymotrypsin. The cultural systems employed thereafter for lactic fermentations were Bifidobacterium bifidum or B. bifidum and Lactobacillus bulgaricus. The viable cell counts, normal- and bile acid tolerances from the mixed cultures of B. bifidum and L. bulgaricus decreased sharply during the initial first 3 days of frozen storage and then showed a gradual decrease thereafter. Melt-down percent of the all frozen products have been favorably affected as was shown by less melting at raised testing temperature during 28 days of frozen storage except for the initial 3 days during which a minor change has been observed. Among the various volatile flavor components, the contents of acetaldehyde, acetone, diacetyl and methanol generally increased during the frozen storage. In sensory test, the frozen soy yogurt prepared with a-chymotrypsin and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.

• 한국식품과학회지
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• 제23권3호
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• pp.286-290
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• 1991

대두의 영양 저해인자로 알려진 phytic acid를 pH를 조절하는 각기 다른 방법으로 제거할 low-phytate soy protein isolate(SPI)와 high-phytate SPI를 얻어 이들 분리 대두단백의 용해도와 소화율에 미치는 phytic acid 함량의 영향을 조사하였다. 분리 대두단백의 phytic acid 함량은 high-phytate SPI에서 2.48%이었고, low-phytate SPI에서는 0.72%이었다. 분리 대두단백의 용해도는 모든 pH에서 low-phytate SPI가 high-phytate SPI 보다 높았으며 phytic acid의 첨가량이 많을수록 용해도가 떨어져 침전되었다. 분리 대두단백의 소화율에 미치는 phytic acid의 저해적 영향은 phytic acid 첨가량이 증가할수록 더 컸으며, low-phytate SPI 보다 high-phytate SPI에서 그 저해효과가 약간 크게 나타났다.

• 한국식품영양과학회지
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• 제45권9호
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• pp.1285-1292
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• 2016

분리콩단백질(SPI, soy protein isolate) 농도, pH, 전해질의 종류와 농도, alginates의 농도와 분자량이 SPI의 표면소수성에 미치는 영향을 조사한 결과는 다음과 같다. SPI 농도가 증가할수록 표면소수성은 감소하였다. SPI의 표면소수성이 pH 7.0에서 최대값을 나타내었다가 pH가 7.0을 기준으로 증가 혹은 감소함에 따라 표면소수성이 감소하는 경향을 나타내었다. SPI의 표면소수성은 NaCl의 농도가 100 mM까지 증가함에 따라 급격히 증가하지만 더 이상의 농도에서는 변화가 없었다. $CaCl_2$와 $MgCl_2$의 농도가 각각 50 mM과 30 mM까지 증가할수록 SPI의 표면소수성이 급격히 감소하였지만, 그 이상의 농도에서는 큰 변화가 없었다. Na-alginate의 농도와 분자량의 증가함에 따라 SPI의 표면소수성이 감소한 것으로 나타났다. Na-alginate의 분자량이 증가함에 따라 표면소수성의 증가속도가 감소하였다.

• 한국식품과학회지
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• 제24권3호
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• pp.204-208
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• 1992

본 실험은 가공한 육제품에 첨가된 대두단백질(soy protein)을 정량하기 위한 면역분석(Immunoassay)법의 개발을 목적으로 실시하였다. Isolated soy protein(ISP)의 whole buffer extract(WBE) 분획을 SDS 처리 후 토끼에 주사하여 생산된 항혈청의 항체역가를 indirect ELISA법으로 조사하였을 시 1 : 10,000 이상에서도 반응을 나타내었다. 시료의 처리시 SDS의 최종농도가 0.03% 이상에서는 항원-항체 반응이 심각하게 저지되었으나, 0.02% 이하에서는 거의 영향을 미치지 않았다. 본 실험에 사용한 항체는 SDS로 변성된 항원(대두단백질)은 물론 SDS를 투석으로 제거한 재생항원(renatured antigen)과도 반응하였으나 그 정도는 변성항원에 비하여 약간 낮았다. 검정곡선(calibration curve)을 indirect competitive ELISA 법으로 작성하였을 시 ISP를 100 ng/100 ml까지 측정할 수 있는 감도(sensitivity)를 얻었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1156-1156
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• 2001

This work aimed to prove the feasibility of NIR spectroscopy to detect vegetable protein isolates (soy, pea and wheat) in milk powder. Two hundred and thirty-nine samples of genuine and adulterated milk powder (NIZO, Ede, NL) were analysed by NIRS using an InfraAlyzer 500 (Bran+Luebbe). NIR spectra were collected at room temperature, and data were processed by using Sesame Software (Bran+Luebbe). Separated calibrations for each non-milk protein added, in the range of 0-5%, were calculated. NIR data were processed by using Sesame Software (Bran+Luebbe). Prediction and validation were made by using a set of samples not included into the calibration set. The best calibrations were obtained by the PLSR. The type of data pre-treatment (normalisation, 1$\^$st/ derivative, etc..) was chosen to optimize the calibration parameters. NIRS technique was able to predict with good accuracy the percentage of each vegetable protein added to milk powder (soy: R$^2$ 0.994, SEE 0.193, SEcv 0.301, RMSEPall 0.148; pea: R$^2$ 0.997, SEE 0.1498, SEcv 0.207, RMSEPall 0.148, wheat: R$^2$ 0.997, SEE 0.1418, SEcv 0.335, RMSEPall 0.149). Prediction results were compared to those obtained using other two techniques: capillary electrophoresis and competitive ELISA. On the basis of the known true values of non-vegetable protein contents, the NIRS was able to determine more accurately than the other two techniques the percentage of adulteration in the analysed samples.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.347-354
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• 2011

Aeromonas salmonicida is an important fish pathogen commonly associated with furunculosis in salmonids. Typical A. salmonicida strains have the surface virulence A-layer protein, a major virulence determinant encoded by the vapA gene. In this study, 880 chum salmon Oncorhynchus keta were collected from the east coast of Korea during 2006-2011, including 560 wild adults and 320 artificially hatched fry pools, and the presence of typical A. salmonicida was examined by PCR using the typical A. salmonicida-specific vapA gene primers. The results demonstrated that 34.5% of the samples (304/880 samples) were PCR positive, implying that a typical A. salmonicida infection is highly prevalent among chum salmon in Korea. Twenty typical A. salmonicida isolates were recovered based on their brown pigmentation on Trypticase Soy Agar (TSA) plates, which indicates the existence of the A-layer protein. Further biochemical analyses with the four randomly selected typical A. salmonicida isolates revealed some variations in their amino acid decarboxylation and carbohydrate fermentation activity. A phylogenetic analysis based on the entire vapA gene sequence suggested that the A. salmonicida isolates from chum salmon were clustered with those isolated from Atlantic salmon in Europe. Further study is needed to resolve such an interesting relationship in detail.