In this study, soy-powder yogurt (SPY) with enhanced levels of γ-aminobutyric acid (GABA) and isoflavone aglycone was produced from sprouting high-protein soybeans (HPSs). The fermented steam-HPS sprouts (0 to 4 cm) were fermented (72 h) with Lactobacillus brevis, and the total free amino acids (FAAs) of the formed mixtures were determined to be 79.53, 489.93, 877.55, 780.53, and 979.97 mg/100 mL in the fermented HPS (FHPS), and the fermented steam-HPS with 0 cm (FSHPS-0), 1 cm (FSHPS-1), 2 cm (FSHPS-2), and 4 cm sprouting lengths (FSHPS-4), respectively. The levels of glutamic acid (GA) and GABA were observed to be the highest, 100.31 and 101.60 mg/100 mL, respectively, in the unfermented HPS (UFSHPS-1, 1 cm) and FSHPS-1 sprouts, respectively. Moreover, the total contents of the isoflavone glycoside form decreased proportionally to the increasing total levels of isoflavone aglycones after fermentation in FSHPS-0, FSHPS-1, FSHPS-2, and FSHPS-4. The levels of isoflavone aglycones were detected as 350.34, 289.15, 361.61, 445.05, and 491.25 μg/g in FHPS, FSHPS-0, FSHPS-1, FSHPS-2, and FSHPS-4, respectively. While FSHPS-1 exhibited the highest DPPH (63.28%) and ABTS (73.28%) radical scavenging activities, FSHPS-4 contained the highest isoflavone aglycone ratio (81.63%). All in all, the FSHPS-1 mixture prepared in this study exhibited high GABA content and functional prosperity, thereby making it suitable for potential applications in the soy-dairy industry.

Introduction
 Materials and Methods
  Sprouting of HPS
  Soy-powder yoghurt (SPY) preparation andfermentation
  Determination of free amino acid contents
  Total phenolics and isoflavones extraction
  Determination of total phenolic contents
  Determination of isoflavone contents
  DPPH assay
  ABTS assay
 Results and Discussion
  Comparison of free amino acids (FAAs), glutamic acid (GA) and γ-aminobutyric acid (GABA) contents
  Comparison of total phenolic contents
  Comparison of radical scavenging activities
 요 약
 Acknowledgment
 References

• Chung Eun Hwang(Department of Food Science, Gyeongnam National University of Science and Technology) | 황정은
• Ok Soo Joo(Department of Food Science, Gyeongnam National University of Science and Technology) | 주옥수
• Md. Azizul Haque(Department of Biochemistry and Molecular Biology, Hajee Mohammad Danesh Science and Technology University) | 모하메드 아지줄 하크만
• Jin Hwan Lee(Division of Research Development and Education, National Institute of Chemical Safety (NICS), Ministry of Environment) | 이진환
• Su Cheol Kim(Department of Food Science, Gyeongnam National University of Science and Technology) | 김수철
• Hee Yul Lee(Department of Food Science, Gyeongnam National University of Science and Technology) | 이희율
• Bong Sik Um(Department of Food Science, Gyeongnam National University of Science and Technology) | 엄봉식
• Kyung Sook Park(Department of Food Science, Gyeongnam National University of Science and Technology) | 박경숙
• Kye Man Cho(Department of Food Science, Gyeongnam National University of Science and Technology) | 조계만 Corresponding author