• Journal of Applied Biological Chemistry
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• 제51권3호
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• pp.88-94
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• 2008

Three different protein extraction methods-phenol extraction, trichloroacetic acid (TCA) precipitation, and desalting/TCA precipitation-were compared to determine the optimal reproducible high resolution 2-dimensional (2-D) electrophoresis for each chungkugjang, doenjang, and kochujang samples. The soluble proteins from Chungkugjang extracted by phenol were separated with high reproducibility and resolution, and gained 1.75- to 3-fold more protein spots on 2-D gel than those from the other methods. On the contrary, the extracted proteins from doenjang and kochujang treated by desalting/TCA precipitation method showed about 1.5- to 3.3-fold more protein spots on 2-D gel. Using the established methods, the changes in the protein profiles of the fermented soy foods were monitored during the fermentation period by 2-DE. One of the major proteins in soy, $\beta$-conglycinin $\alpha$-subuint, and some proteins with unknown functions were localized on 2-D gel as the protease-resistant proteins throughout the fermentation period of doenjang. Changes in the protein profile monitored by the established methods can provide basic information on unfolding the mechanisms of the generation of biofunctional activity in the fermented soy foods.

• 한국식품저장유통학회지
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• 제30권5호
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• pp.875-884
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• 2023

본 연구에서는 탈지대두분말로 제조한 식물조직단백(texturized vegetable protein)과 분리대두단백, 탈지하지 않은 대두분말로 제조한 식물조직단백의 품질 특성을 비교 분석하였다. 원료의 배합은 대두단백 50%, 글루텐 30%, 옥수수전분 20%를 기본배합으로 하였다. 냉각 다이가 장착된 압출성형기를 이용하여 배럴온도 190℃, 스크루 회전속도 250 rpm으로 하였다. 분리대두단백 대비 경도는 대두분말이 22.4%, 탈지대두분말이 68.8% 수준이며, 검성은 대두분말이 17.6%, 탈지대두분말이 44.3% 수준으로 나타났고, 탈지를 통하여 씹힘성, 절단강도, 탄력성이 증가하였다. 대두분말과 탈지대두분말의 수분함량은 대두분말 처리구가 높았으며, 수분흡수력과 탁도는 유의적인 차이가 없었다. pH는 대두분말 처리구가 탈지대두분말보다 높았으며 색도는 L값과 b값은 대두분말 처리구가, a값은 탈지대두분말 처리구가 높게 나타났다. 이상의 결과에서 대두를 탈지하여 사용할 경우 식물조직단백 품질의 개선 정도를 확인하였으며, 분리대두단백과의 품질 차이를 개선할 수 있는 다양한 연구가 필요할 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.775-783
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• 2007

To elucidate the efficacy of different soy protein sources on piglet's performance, a total of 280 weaned piglets ($Duroc{\times}Yorkshire{\times}Landrace$, $23{\pm}3$ d of age, $5.86{\pm}0.45$ kg initial BW) were allotted to 5 treatment diets comprising soybean meal (SBM), soy protein concentrate (SPC), Hamlet protein (HP300), fungal (Aspergillus oryzae) fermented soy protein (FSP-A), and fungal plus bacterial (A. oryzae+Bacillus subtilis) fermented soy protein (FSP-B), respectively. Experimental diets for feeding trial were formulated to contain each soy protein sources at 8% level to corn-whey powder basal diet. There were 14 pigs per pen and 4 pens per treatment. Experimental diets were fed from 0 to 14 d after weaning and then a common commercial diet was fed from 15 to 35 d. Also for ileal digestibility studies, 18 pigs were assigned to 6 dietary treatments as N-free, SBM, SPC, HP300, FSP-A and FSP-B with T-canulation at distal ileum for 6 days. At $14^{th}$ d of experimental feeding, the ADG was significantly higher (p<0.05) in SPC fed diet as compared with others. Similar trend was noticed during the 15-35 d and overall study (0-35 d). All the processed soy protein sources tested in this experiment improved (p<0.05) growth than SBM during overall study. The nutrient digestibility of GE, DM, CP and Ca showed lower (p<0.05) values in SBM and FSP-A fed groups than SPC and FSP-B treatments. The apparent ileal digestibility of TEAA, non-TEAA and TAA showed lower (p<0.05) in SBM treatments compared with other soy protein sources. The true ileal digestibility of TEAA, non-TEAA and TAA were lower (p<0.05) in SBM fed group than SPC and HP300 treatments, and lower than FSP treatments though they didn't achieve significant difference (p>0.05). Villous height and crypt depth was not affected by dietary treatments. In conclusion, the growth and digestibility of nutrients in weaned pigs fed SPC was superior to others. Also FSP-A and FSP-B showed improved performance than those fed SBM.

• 한국식품과학회지
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• 제31권3호
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• pp.757-763
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• 1999

R. stolonifer를 접종하여 콩알메주를 제조하고 이 콩알메주로부터 한식간장을 생산하는 공정을 설정하였다. 콩알메주의 최적 발효조건은 온도와 상대습도가 각각 $25^{\circ}C$, 90%인 조건에서 45시간 발효하는 것이었다. 간장의 최적 숙성온도는 $25^{\circ}C$가 적정온도였으며 발효후반의 aeration에 의하여 관능이 향상되었고 R. stolonifer로 제조한 콩알메주만 사용하여 숙성시킨 간장보다는 A. sojae나 B. subtilis로 제조한 콩알메주를 혼합하였을 때에 관능이 향상되었다. 간장을 상품화하기 위한 공정으로 살균, ultrafiltration에 의한 여과, 보존성 등을 제시하고 이를 종합하여 표준화된 콩알메주 및 한식간장 model system의 공정예로 설정하였다. 본 연구에서 제시된 공정예를 통하여 일반적으로 메주와 한식간장 발효에 소요되는 $6{\sim}12$개월의 시간을 3개월 이내로 단축할 수 있었고 생산된 제품의 색, 향, 맛 등의 관능평가가 우수하였으며 기술적으로는 자동화가 가능하여 본 연구의 결과를 한식간장의 산업화된 model system으로 제시하였다.

• Current Research on Agriculture and Life Sciences
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• 제32권1호
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• pp.34-42
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• 2014

Soy and fermented soy are popular and recognized as a health food among Koreans. Since soy proteins are known to be protease resistant, even to pepsin and pancreatin, it is hypothesized that soy proteins may interact with the intestinal tract and trigger certain physiological reactions. To test this hypothesis, mice were fed diets supplemented with soy, Chunkukjang, or casein. The differentially expressed proteins were analyzed using 2-D gels and identified by peptide mass fingerprinting using mass spectrometry. The majority of the differentially expressed proteins could be functionally grouped into metabolic enzymes and calcium-binding proteins. The differential protein expression by the soy-fed groups was also verified based on a representative protein, tropomyosin, using a Western blotting analysis. In addition, the soy-fed groups exhibited a taller villi structure. Therefore, this study suggests that soy proteins can be an effective nutrient and physiological stimulant for the intestines.

• 한국식품영양과학회지
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• 제26권5호
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• pp.784-787
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• 1997

Enzymatically hydrolyzed soy sauce(eHSS) was prepared by the treatment of defatted soy flake using two types of proteases, followed by maillard reaction and formulation with some ingredients. The eHSS was mixed with fermented soy sauce(FSS) to make enzymatically hydrolyzed mixed soy sauce(eHMSS). The properties and sensory characteristics were evaluated and compared with commercially available soy sauces. The control of salt and total nitrogen contents in eHSS and eHMSS was easy, and the production of soy sauce of low salt and high protein was possible. However, the free amino acid content of eHSS was lower than FSS. due to lower degree of hydrolysis. In sensory evaluation, the eHSS have no loss taste and overall acceptance than FSS. Consequently, the eHSS and eHMSS have the potential for use with FSS to produce high quality soy sauce of low salt and high protein contents.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제22권8호
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• pp.1167-1173
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• 2009

This study was conducted to evaluate the effects of providing fermented soy protein to weaned pigs on nitrogen balance and apparent fecal and apparent ileal digestibility (AID) of AA. Four weaned ((Yorkshire${\times}$Landrace)${\times}$Duroc) barrows (BW = 6.58${\pm}$0.98 kg), surgically fitted with a simple T-cannula approximately 15 cm prior to the ileo-cecal junction, were fed four diets according to 4${\times}$4 Latin square design. Diets were a basal diet supplemented with one of the following: 3% SDPP (spray dried plasma protein), 5% RBP (soy protein fermented by Lactobacillus spp.), 5% PSP (soy protein fermented by Aspergillus oryzae and Bacillus subtilis), and 2.5% RPP (2.5% RBP+2.5% PSP). No differences were observed in DM and N intakes among treatments. However, the level of urine excretion was greater in the RPP group than in the PSP group. Additionally, fecal DM excretion, fecal N concentration and fecal N excretion were increased in the RBP, PSP and RPP groups when compared with the SDPP group (p<0.05). Furthermore, total excretion was increased in the RPP group when compared with the PSP group (p<0.05). In addition, N absorption and the N absorption ratio were higher in the SDPP group than in the RPP group (p<0.05). Moreover, the DM and N digestibilities were lower in the RBP, PSP and RPP groups than in the SDPP group (p<0.05), and the ash and energy digestibilities were higher in the SDPP and RBP groups than in the PSP and RPP groups (p<0.05). However, no significant differences were observed in the DM, N, Ash, Ca, P or ileal digestibilities among treatments, although the energy digestibility was higher in the SDPP group than the RBP group (p<0.05). In addition, the apparent ileal digestibilities of essential amino acids (Arg, His, Iso, Leu, Lys, Phe, Thr, and Val) were significantly higher in the SDPP group than in the other groups (p<0.05), and the levels of Ala, Cys, Glu and Try were greater in the SDPP treatment group than the RBP, PSP and RPP groups (p<0.05). Additionally, the levels of Asp, Gly and Ser were higher in the SDPP group than the PSP and RPP groups, and the level of Pro was higher in the SDPP group than the RPP group (p<0.05). Finally, total non-essential amino acid and total amino acid digestibility were higher in the SDPP group than in the other treatments (p<0.05). Taken together, the results of this study indicate that animal protein is more bioavailable than plant protein. However, the N absorption ratio and ileal digestibility were found to be similar in the SDPP and RBP groups.

• 한국식품조리과학회지
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• 제15권1호
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• pp.73-80
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• 1999

This study was carried out to investigate the effects of enzyme treatments on the functional properties of soy protein isolate (SPI) and to examine the quality attributes of soy yogurt prepared by different enzyme treatments, sweeteners and starter cultures. Enzyme treatment increased the solubility and emulsifying capacity of soy proteins, but decreased the emulsifying stability; the enzymatic activity of ${\alpha}$-chymotrypsin was higher than that of trypsin. Enzyme treatments decreased the pH of soy yogurts prepared by both culture methods, the culture of L. bulgaricus and S. thermophilus and the culture of L. bulgaricus and K. fragilis, but increased the titratable acidity, total numbers of lactic acid bacteria and yeast. Trypsin was more effective than ${\alpha}$-chymotrypsin in decreasing pH and increasing titratable acidity and total numbers of lactic acid bacteria and yeast. Fructose decreased the pH of soy yogurts more than sucrose in the culture of L. bulgaricus and S. thermophilus, and vice versa in the culture of L. bulgaricus and K. fragilis. Fructooligosaccharides were more effective in the culture of L. bulgaricus and K. fragilis than in the culture of L. bulgaricus and S. thermophilus in increasing the titratable acidity, total count of lactic acid bacteria and yeast. In sensory evaluation, soy yogurts containing trypsin treated SPI, fructose and fructooligosaccharides (75%:25%) were more acceptable than those containing untreated or trypsin treated SPI and fructose. This was because of more smooth and less sour, in which the values of pH, titratable acidity, microbial growth, and viscosity were in the range of commercial yogurts. Soy yogurts fermented by L. bulgaricus and K. fragilis showed more smooth mouthfeel than those fermented by L. bulgaricus and S. thermophilus.

• 한국식품과학회지
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• 제17권1호
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• pp.51-53
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• 1985

본 연구는 전지대두분(全脂大豆粉), 탈지대두분(脫脂大豆粉) 농축대두단백(SPC), 분리대두단백(SPI)으로 만든 대두유산균음료의 향미(香味)를 비교관찰하고, 유산균발효가 두유의 향미(香味)와 몇가지 휘발성분에 미치는 영향을 조사한 것으로서 그 결과를 요약하면 다음과 같다. 대두유산균음료는 reference로 사용된 우유유산균음료보다 향미(香味)가 떨어졌으며, 대두유산균음료 가운데는 SPI 유산균음료의 향미(香味)가 가장 우수했고 전지대두(全脂大豆) 유산균음료의 향미(香味)가 가장 저조했다. Hedonic scale과 2점기호실험(點嗜好實驗)의 결과를 보면 SPI 유산균음료의 향미(香味)가 SPI두유의 향미(香味)보다 훨씬 우수했다(P<0.01). 유산균발효에 의하여 SPC두유와 SPI두유에 함유된 n-hexanal은 감소하였고, diacetyl을 증가하였다.