Mutation of Acetobacter pasteurianus by UV irradiation under acidic stress for high‐acidity vinegar fermentation

Abstract

SummaryTo obtain a mutant with higher vinegar production, a wild‐type industrial strain Acetobacter pasteurianus CICIM B7003 was pretreated in 50 g L−1 acetic acid for 1 h and cultured for 12 h without adding any acetic acid; then, the enriched cells were mutated by UV under acidic stress (60 g L−1 acetic acid). Using this method, A. pasteurianus CICIM B7003‐02, a mutant exhibiting best performance, was obtained. Notably, after repeated experiments, it was confirmed that B7003‐02 accumulated 103.81 ± 1.17 g L−1 acetic acid within 160‐h batch cultivation in Erlenmeyer flasks, which was 49.2% higher than that of the wild type. Repeated batch fermentations with A. pasteurianus B7003‐02 were carried out for several runs in a Frings 8‐L acetator, and high‐acidity vinegars (90 ± 0.39 g L−1) were produced. This work reveals the potential value for improvement in industrial vinegar production.