오미자(Schizandra chinensis) 열매 추출물의 Lactobacillus plantarum 젖산발효를 통한 고농도 GABA 함유 발효음료 제조

Omija (Schizandra chinensis) extract (OE) was fermented by using Lactobacillus plantarum EJ2014 to produce a beverage fortified with gamma-aminobutyric acid (GABA). After 2 days of fermentation in the presence of 2% monosodium glutamate (MSG) and 0.5% yeast extract (YE), the four-fold-diluted OE showed a higher viable cell count (2.2×109 CFU/mL) and lower acidity (1.2%) than that of the unfermented OE. In particular, addition of MSG as a precursor resulted in a small increase in the initial pH. MSG (2%) was completely converted to GABA (0.92%) during lactic acid bacteria fermentation for 3 days. Furthermore, the acidity of the fermented OE decreased from 1.74% to 0.56%. In addition, the original red color of the OE disappeared during LAB fermentation. However, when the fermented OE was mixed with 50% of the original OE, the original red color was recovered, with 19.56 and 13.92 for Hunter L and a values, respectively. The mixture of 50% original OE and 50% fermented OE showed the highest sensory score including the highest overall preference. In conclusion, the OE fortified with GABA and probiotics was produced by fermentation with a static culture, L. plantarum EJ2014.