Abstract: In this study, three functional strains of aroma-producing yeast, highly efficient acid-producing acetobacter and polysaccharide-producing lactic acid bacteria were applied in the enhanced fermentation of Baoning vinegar. Results of enhanced fermentation with single starter cultures showed that compared with the control group, the number and relative contents of volatile compounds in vinegar fermented with aroma-producing yeast were improved by 17.39% and 20.23%, which were 27 and 79.65%, respectively, and the acidity of the samples fermented with acid-producing acetobacter and polysaccharide-producing lactic acid bacteria were increased by 82.75% and 155.75%, which were 3.18% and 4.45%, respectively, along with an increase in organic acid concentration of 23.46%?389.21%. Additionally, the polysacchairde concentration of the vinegar fermented by the third starter culture was up to 1 143.78 mg/L, which was 68.43% higher than that of the control group. Mixed culture fermentation containing 40% yeast, 16% acetic acid bacteria and 44% lactic acid bacteria at an inoculum size of 1% was demonstrated to be optimal for obtaining the best product, which had an acidity of 5.28%, contained 30 volatile compounds and scored 85.65 points in sensory evaluation. This research can provide a theoretical support for improving the flavor and yield of?Baoning vinegar.

Key words: aroma-producing yeast, high acid-producing acetobacter, polysaccharide-producing lactic acid bacteria, Baoning vinegar, enhanced fermentation, mixture design