Selection and characterization of acetic acid bacteria from traditional Korean vinegars for starter culture development

Acetic acid bacteria (AAB) play a key role in vinegar fermentation by oxidizing ethanol to acetic acid and contributing to aroma development. In this study, ten AAB strains isolated from Korean traditional vinegars were evaluated for acid production and volatile compound profiles. Among them, Acetobacter pasteurianus B7 and A. pasteurianus JGB 20-11 showed high acetic acid production and distinct volatile profiles, characterized by fruity and floral compounds such as methyl acetate and methyl isobutyrate. These strains were therefore selected as candidate starter cultures, and subsequent fed-batch cultivation showed high acetic acid production (100.59 g/L), along with increased cell densities and negligible by-product formation. The biomass of both strains was lyophilized, and the resulting starter cultures formulated with maltodextrin and lactomil showed low moisture contents (0.80-3.95%) and low water activity (Aw<0.6), indicating microbiological and physicochemical stability. These findings support the development of indigenous AAB starter cultures and contribute to improving the quality and consistency of fermented foods.