Integral use of brewery wastes as carbon and nitrogen sources for the bioproduction of succinic acid

Abstract

Circular bioeconomy is one of the major socio-economic objectives for the twenty-first century, which includes the use of biomass waste and its transformation through environmentally friendly processes into biorefinery building blocks. Among these compounds, succinic acid (SA) obtained by fermentation stands out. This work demonstrates the feasibility of using beer bagasse and spent brewer’s yeast as carbon and nitrogen sources for the bioproduction of SA with Actinobacillus succinogenes. The use of a progressive enzymatic treatment liberated simple monosaccharides and peptides that were used by the microorganism, in a subsequent fermentation. Compared to the use of commercial xylose and yeast extract, the used of beer wastes obtained better yields (0.77 g g −1) and selectivity (76%), though with a slightly lower productivity (0.15 g L −1 h −1). Finally, an unstructured non-segregated kinetic model was successfully fitted, facilitating the future performance of bioreactor design, techno-economic analysis, scaling of the process, or design of a control system.