In this study, contetnts of phenolic acid and isoflavone, and biological activities of soy sauce were compared the soy sauce added bitter melon powder (BMPs). After the fermentation, pHs were decreased from 5.83 (0% BMP), 5.47 (5% BMP), and 5.32 (10% BMP) to 5.28, 5.36, and 5.16 at 90 days, whereas the acidities of soy sauce were increased from 0.06%, 0.07%, and 0.09% to 0.30%, 0.28%, and 0.36% at 90 days, respectively. In addition, the salinities of soy sauce were decreased, while viable cell numbers including Bacillus and yeast were increased. The contents of total phenolic, isoflavone-aglycone, and phenolic acid and antioxidant and α-glucosidase inhibition activities were significantly increased for 90 days, while the isoflavone-glycoside contents were decreased. In Particular, soy sauce with 10% BMP at 90 days showed the highest contents of glutamic acid (GA, 9,876.09 mg/100 mL) and γ-aminobutyric acid (GABA, 325.02 mg/100 mL) contents than among other samples. Additionally, the radical scavenging activities (DPPH, ABTS, ⦁OH, and FRAP) and α-glucosidase inhibition activities of soy sauce with 10% BMP at 90 days were shown to be high 96.07%, 97.27%, 59.47%, 1.98%, and 79.96%, respectively.

• Chung Eun Hwang(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 황정은
• Dong Hee Lee(Gyeongbuk Institute for Bioindustry, 경북바이오산업연구원) | 이동희
• Ok Soo Joo(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 주옥수
• Hee Yul Lee(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 이희율
• Su Cheol Kim(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 김수철
• Kyung Sook Park(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 박경숙
• Bong Sik Um(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 엄봉식
• Kye Man Cho(Department of Food Science, Gyeongnam National University of Science and Technology, 경남과학기술대학교 식품과학부) | 조계만 Corresponding author