Investigation of vinegar production using a novel shaken repeated batch culture system

Abstract

Nowadays, bioprocesses are developed or optimized on small scale. Also, vinegar industry is motivated to reinvestigate the established repeated batch fermentation process. As yet, there is no small-scale culture system for optimizing fermentation conditions for repeated batch bioprocesses. Thus, the aim of this study is to propose a new shaken culture system for parallel repeated batch vinegar fermentation. A new operation mode - the flushing repeated batch - was developed. Parallel repeated batch vinegar production could be established in shaken overflow vessels in a completely automated operation with only one pump per vessel. This flushing repeated batch was first theoretically investigated and then empirically tested. The ethanol concentration was online monitored during repeated batch fermentation by semiconductor gas sensors. It was shown that the switch from one ethanol substrate quality to different ethanol substrate qualities resulted in prolonged lag phases and durations of the first batches. In the subsequent batches the length of the fermentations decreased considerably. This decrease in the respective lag phases indicates an adaptation of the acetic acid bacteria mixed culture to the specific ethanol substrate quality. Consequently, flushing repeated batch fermentations on small scale are valuable for screening fermentation conditions and, thereby, improving industrial-scale bioprocesses such as vinegar production in terms of process robustness, stability, and productivity.

Aerobic submerged fermentation by acetic acid bacteria for vinegar production: Process and biotechnological aspects

“…Oxygen deprivation can be harmful not only during SF but also during the transfer of cultures from the precultivation flasks to the acetators and during any transfer from one acetator to another. To reduce bacteria death and to maintain a high respiration activity throughout the whole fermentation process, a so-called RAMOS (respiration activity monitoring system) device, that ensures a constant oxygen supply, was recently proposed [52]. With this method, cultures drained off from bioreactors can be transferred into an aerated bubble column and transported without an interruption of the oxygen supply.…”

Vinegar Engineering: a Bioprocess Perspective

“…The transfer of oxygen during a fermentation process requires hydrostatic pressure monitoring and reduced mechanical influences such as stirring speed on the cells. Other factors to consider when transferring oxygen for vinegar production are the microorganisms used and their oxygen uptake rate [36,82].…”

Production of vinegar using edible alcohol as feedstock through high efficient biotransformation by acetic acid bacteria

“…The followed stage is semi-continuous biotransformation stage, which is the main vinegar production [3]. The vinegar production efficiency mainly depends on the process parameters of the two stages [5][6][7][8][9][10][11]. To find the optimal conditions for the two stages is significant to improve the vinegar production.…”