In vitro digestibility and protein digestibility corrected amino acid scores (PDCAAS) were investigated to verify the availability of protein in various Rhizopus oligosporus fermented products of domestic soybean (Glycine max L.) cultivars. Danbaegkong (DBK), Daepung (DP), Daewonkong (DWK), Saedanbaek (SDB), Seonyu (SY), and Cheongja4ho (CJ4) were used as raw samples, which were fermented using commercially available Rhizopus oligosporus for 48 h. All cultivars showed increased crude protein content after fermentation. The crude protein content of DBK and SDB was significantly higher than that of the other samples (55.12% in DBK and 54.22% in SDB) (p<0.001). CJ4 had the highest alanine content of 28.88 mg/g (p<0.001), and no significant difference in cysteine content was detected among the cultivars. In most of the fermented samples, the in vitro digestibility was 0.9 or higher, indicating high protein in the fermented samples. However, it is considered that restrictions on digestion are low. In DWK, the amino acid content and PDCAAS, which together indicate protein quality, were 0.917 and 0.855, respectively, confirming that it was the best cultivar to provide the raw material for fermentation. In conclusion Rhizopus oligosporus fermented soybean products can be considered a prospective source of protein with high utility value.

This study analyzed the nutritional composition properties of soybeans and the antioxidants, isoflavones, organic acids, and volatile flavor compounds of fermented black soybean products (FBSP). After 24 hours of fermentation, the range of water uptake ratio was 129.00-131.30%, respectively. Total polyphenols content and DPPH and ABTS radical scavenging activity were higher in Cheongja-3 FBSP, flavonoids in Socheongja, while DPPH and ABTS radical scavenging activities were similar in Cheongja-3 FBSP. Isoflavone contents of aglycones (daidzein, genistein, and glycitein) in Cheongja-4 FBSP increased up to 41.97 μg/g. The rank order of primary organic acids was citric acid > fumaric acid > acetic acid > lactic acid, with Cheongja-3 FBSP being the highest. This study identified a total of 34 volatile aroma-compounds, including seven alcohols, seven acids, seven ketones, five phenols, two esters, one furan, four pyrazines, and one miscellaneous. The result could be applied to determine the suitability of cultivars and the quality of the process used for fermented soybean products.

In this study, the properties of the substances fermented soybean producted by manufacturing with several Aspergillus strains were investigated. The five soybean cultivar that includes miso, jinpung, pyeongwon, cheonga and chamol were used in this experiment. The pH and total acidity were 6.30~6.66%, and 0.27~0.48%, respectively with differences depending on the samples. The color values for L value, a, and b value were 60.28~69.80, 0.64~3.68, and 11.48~31.21, respectively. The amylase activities, protease activities, and amino-type nitrogen of the jinpung samples were the highest among all cultivars. The mold counts the fermented soybean products by cultivars were 6.18~9.14 log CFU/g, and miso was the highest. Free amino acid and organic acid contents were highest in the jinpung and showed different composition depending on each sample. A total of 18 volatile aroma-compounds, including two acids, four alcohols, four ketones, three phenols, one furan, three pyrazines, and one miscellaneous compounds. In conclusion, it is expected that manufacturing A. oligze inoculation fermented soybean products using jinpung cultivar will improve quality.

This study evaluates the quality properties of soybean cultivar for fermented soybean products with several Aspergillus spp., which were selected based on their high antimicrobial activities. The six soybean varieties Daewonkong, Taekwangkong, Jinpung, Daechan, Daepung-2, and Seonpung were used in the experiment. Physicochemical analysis of soybeans showed that the cured fat and protein contents were 18.28-19.15 and 36.49-38.72%, respectively. The pH and total acidity (TA) were 6.31-6.60 and 0.36-0.48%, respectively. The amino nitrogen contents of all samples were in the range of 641.23 to 791.12 mg%, while Daechan showed the highest content (791.12 mg%). Mold counts of fermented soybean products were 7.63-9.20 log CFU/g. Hunter color values for L value, a value, and b value ranged from 59.52-71.28, 0.11-3.03, and 14.61-31.70, respectively. The amylase and protease activities of the Daepung-2 and Daechan were the highest among all the cultivars. The rank order of major free amino acids was glutamic acid > lysine > alanine > aspartic acid, with Daepung-2 and Daechan being the highest. As a result, Daepung-2 was suitable as a soybean cultivar, exhibiting high quality standards for the fermentation process of the fermented soybean products.

In this study, we analyzed the nutritional composition properties of soybeans and the organic acids, amino acids and volatile flavor compounds of fermented soybean products. We used five soybean cultivars including Pyeongwon, Jinpung, Saedanbaek, Saeolkong and Cheonga for this experiment. Physicochemical analysis of soybeans, showed that the cured protein and fat contents were 35.12∼45.12 and 14.26∼20.14%, respectively. The rank order of major organic acids was lactic acid > acetic acid > fumaric acid, with Saedanbaek being the highest. Total amino acid content of the samples was 358.12∼657.28 mg/100 g, and glutamic acid, alanine, cysteine, valine, leucine, histidine and arginine were the major amino acids. We identified a total of 34 volatile aroma-compounds, including 7 alcohols, 7 acids, 7 ketones, 5 phenols, 2 esters, 1 furan, 4 pyrazines, and 1 miscellaneous compounds. As a result of this, could be applied to determine the suitability of cultivars and the quality for the process of the fermented soybean products.

This study evaluates the quality properties of soy-paste soybean cultivar for fermented soybean products. The six soybean varieties that include Jinpung, Saedanbaek, Daepung 2, Pyeongwon, Cheonga and Saeolkong were used in the experiment. The range of water uptake ratio, hardness after soaking and hardness after steaming were 117.00~131.33%, 1.65~3.30 kg and 0.05~0.14 kg, respectively. The physicochemical analysis indicated the following: Moisture content, 63.27~68.72%; pH, 6.43~6.60; total acidity, 0.27~0.45%. Color values for L value (lightness), a value (redness), and b value (yellowness) ranged from 39.07~67.92, 7.64~11.79, and 7.48~20.67, respectively. The amylase and protease activities of the Saedanbaek samples were the highest among all cultivars. The amount of viscous substance in the fermented soybean products by cultivars ranged from 5.93 to 8.37%, and Saedanbaek was the highest. The total viable cells counts for soybean fermented products were 9.11~9.42 log CFU/g. The amino-type nitrogen contents of all samples were in the range of 401.07 to 524.47 mg% and Saedanbaek cultivars showed the highest content (524.47 mg%). Based on the results, Saedanbaek will be suitable as a soy-paste soybean cultivar and the quality standards for the fermentation process of the fermented soybean products.

전통장류로부터 분리 된 효소 활성 및 probiotic효과가 우수한 유산균을 접종하여 제조된 콩 발효물의 품질특성을 분석하였다. 일반세균수는 유산균을 접종한 콩 발효물이 4.10×109-7.75×109 CFU/mL으로 나타났다. 유산균수를 측정 결과 유산균을 접종한 콩 발효물은 2.85×109-4.35×109 CFU/mL으로 높게 나타났다. α-Amylase 활성 측정 결과 I13과 JSA22를 접종한 콩 발효물은 1.05±0.91, 3.13±1.39 unit/mL으로 가장 낮았다. 또한 JSB22는 12.56±1.39 unit/mL으로 유산균 접종 콩 발효물 중 가장 높았다. Protease 활성 측정 결과, control이 333.13±17.68 unit/mL으로 가장 높았으며, 유산균을 접종한 콩 발효물은 JSB22를 접종한 콩 발효물이 166.67±2.37 unit/mL으로 높았다. 환원당 함량을 측정한 결과 유산균 접종 콩 발효물 중 JSB22가 1.23±0.035%로 가장 높았다. 아미노태 질소 함량 또한 JSB22가 94.52±3.86 mg%으로 높게 나타났다. 아미노산함량을 측정한 결과 glutamic acid, aspartic acid, arginine, leusine 순으로 많이 함유하고 있었다. 유기산 함량을 분석한 결과 lactic acid, oxalic acid가 많이 측정되었다. 향기분석 측정 결과 총 39종(ester류 2종, ketose 5종, alcohol 7종, hydrocarbons 14종, heterocyclic compounds 3종, acid 4종, other 5종)이 검출되었다. 세 가지 균주에서 공통적으로 benzene(81.43-98.54 ppm)과 acetic acid, ethyl ester(44.79-56.74 ppm)가 많이 검출되었다. 본 연구는 전통장류 유래 기능성 우수 유산균주를 이용한 콩발효물의 기초적 품질특성에 관한 내용으로 미생물학적 및 이화학적 관련 특성을 분석하여 제시하였다. 유산균 이용 생물전환에 의한 다양한 기능성 물질이 생성 되었을 것으로 생각된다. 본 연구결과가 기능성 콩 발효소재 개발의 좋은 기초자료가 될것으로 생각되며, 장류 품질개선 기능성 스타터 개발에 활용 될 수 있을 것으로 기대된다.