In this study, we developed vinegar depending on the quantity consumed and type of peeled and unpeeled roots of Platycodon grandiflorum (PG) using Acetobacter pasteurianus A11-2, analyzed vinegar samples using colorimeter and HPLC for 15 days to assess the characteristics on quality, and evaluated their antioxidant activity using 1,1-diphenyl-2-picry1 hydrazy1 (DPPH) and 2.2’-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities. The major result in PG vinegar was the high acidity of 6.39~6.74% and alcohol was totally converted on the 15th day of fermentation. When we fermented vinegar from peeled roots of 8% PG with a starter culture, we observed high contents of acetic acid, platycodin D, and total polyphenol and high antioxidant activity. Moreover, the vinegar fermented using 8% peeled roots of PG had the high intensity on umami and sour taste and low salty, bitter, and astringent tastes. Consequently, we could develop the PG vinegar with quality and functional characteristics from 8% peeled roots and A. pasteurianus A11-2.

This research was carried out to find herbal preservatives for Makgeolli, as Makgeolli loses its commercial value due to overproduced acidic materials. When Makgeolli was kept at 25℃ to find the changes in acidity, total microbial cell number, yeast cell number, and bacterial species variety, a sudden increase of acidity as well as the disappearance of yeast cells occurred at day 6, and Makgeolli was changed to complete off-flavor. Acetobacter pasteurianus is the main acidifier in Makgeolli and shows a synergy effect in acid formation when cultured in combination with Lactobacillus casei. Among 12 herbs, the ethanol extract of Sutellaria baicalensis showed antimicrobial activity against A. pasteurianus, whereas the ethanol extract of Coptidis rhizoma showed antimicrobial activity against L. casei. Makgeolli added with Sutellaria baicalensis extracts demonstrated a lower acidity than that with Coptidis rhizoma extracts, which indicates that the inhibition of an acetic acid former is more important than that of a lactic acid former in Makgeolli preservation. Sutellaria baicalensis extracts prolonged the shelf life of Makgeolli by 1～2 weeks at a minimal inhibitory concentration (0.63 ㎎/㎖) during storage at 10℃.