Volatile fatty acids (VFA) and medium chain carboxylic acids (MCCAs) are needed in several branches of the chemical industry such as in pharmaceutics, food, and feed, making a biorefinery inspired production that starts from low-grade biomass an interesting alternative to conventional petrochemical processes. In this study, butyric, valeric and caproic acid were produced with a defined co-culture of Megasphaera cerevisiae and Pediococcus pentosaceus by utilizing food waste residue, hydrolyzed cabbage, as the sole carbon source. The developed process was scaled-up to 25 L and coupled with a modified electrodialysis for in-situ product removal to limit the concentrations of accumulating VFAs and MCCAs in the fermentation broth. This process resulted in titers of 10.98 g L-1, 6.19 g L-1 and 0.23 g L-1 of butyric, valeric acid and of caproic acid, respectively, showing that MCCAs and VFAs of growing demand can be produced via valorization of organic residues from waste streams.
