Quality characteristics of seomaeyaksuk (Artemisia argyi H.) vinegar using a three-step continuous fermentation method

Abstract

This study was conducted to develop fermented foods using Artemisia argyi H. (seomaeyaksuk) and identify its activity. Vinegar was completed through a three-step fermentation process (lactic acid fermentation, alcoholic fermentation, and acetic acid fermentation). A sikhye added with 15% seomaeyaksuk water extract was used as the fermentation substance. Each sikhye was added with 0, 0.25, 0.5, and 1.0% monosodium glutamic acid (MSG) to enhance γ-aminobutyric acid (GABA) content and then fermented at 30°C for 3 days with Lactobacillus brevis (KI271266). GABA content increased with fermentation period and was the highest in the MSG 1.0%-added sample (354.38 mg/L). Saccharomyces cerevisiae starter was inoculated for alcohol fermentation and analyzed at 0, 2, 4, and 6 days. During alcohol fermentation, alcohol content was 1.75~5.35% at 2 days, and was the highest in the 0.25% MSG-added group. After 6 days of alcohol fermentation, Acetobacter pasteurianus A8 was inoculated for acetic acid fermentation for 20 days. Samples were taken at 4-day intervals. pH level decreased while acid content gradually increased during fermentation. Seven kinds of organic acids were detected, and acetic acid content was most abundant. GABA contents were higher 6.5- and 14-fold higher in the MSG 0.25%- and 1.0%-added samples, respectively, compared to the non-MSG sample. After completion of acetic acid fermentation, the total polyphenol content of vinegar was higher in the MSG 1.0%-added sample compared to the 0~0.5% MSG-added samples. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity was also higher in the 1.0% MSG-added sample than others. Based of these results, we confirmed that the addition of MSG enhanced GABA contents and antioxidant activity as a result of the complex action of vinegar itself, the active ingredient of seomaeyaksuk, and new products of the fermentation process. ? 2018, Korean Society of Food Science and Nutrition. All rights reserved.