The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, γ-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.

Abstract
서 론
재료 및 방법
    1. 실험재료
    2. 고구마 발효물 제조
    3. pH 및 적정산도 측정
    4. 유산균수 측정
    5. 유기산 함량 측정
    6. γ-Aminobutyric acid(GABA) 함량 측정
    7. 총 폴리페놀 및 총 플라보노이드 함량 측정
    8. ABTS radical 소거활성 측정
    9. DPPH radical 소거활성 측정
    10. 환원력 측정
    11. 통계처리
결과 및 고찰
    1. pH 및 적정산도
    2. 유산균수의 변화
    3. 유기산 함량
    4. γ-Aminobutyric acid(GABA) 함량
    5. 총 폴리페놀 및 총 플라보노이드 함량
    6. ABTS radical 소거활성
    7. DPPH radical 소거활성
    8. 환원력
요약 및 결론
References

• 하기정(경상남도농업기술원 농촌자원과) | Gi Jeong Ha (Rural Resources Division, Gyeongsangnam-do Agricultural Research & Extension Services) Corresponding author
• 김현영(경상남도농업기술원 농촌자원과) | Hyeon Young Kim (Rural Resources Division, Gyeongsangnam-do Agricultural Research & Extension Services)
• 하인종(경상남도농업기술원 농촌자원과) | In Jong Ha (Rural Resources Division, Gyeongsangnam-do Agricultural Research & Extension Services)
• 조성래(경상남도농업기술원 농촌자원과) | Sung Rae Cho (Rural Resources Division, Gyeongsangnam-do Agricultural Research & Extension Services)
• 문진영(경상남도농업기술원 작물연구과) | Jin Young Moon (Agricultural Product Research Division, Gyeongsangnam-do Agricultural Research & Extension Services)
• 서권일(동아대학교 생명공학과) | Gwon Il Seo (Department of Life Resources Industry, Dong-A University)