WG2: Production of carboxylic acids as platform molecules

Carboxylic acids or volatile fatty acids (VFAs) are inexpensive and renewable carbon sources that can be generated from anaerobic digestion of different feedstock. Given the great heterogeneity of the food waste, agricultural residues or even lignocellulosic feedstock, this process is considered very technologically favorable for obtaining a source of carbon assimilable by the yeasts. Furthermore, the process is almost completely independent of the composition of the substrate. When limiting the anaerobic digestion to the first three stages to avoid the production of biogas, the organic matter contained in the waste results in a mixture of VFAs. These compounds, can have different chain lengths (between C2-C6) and their prevalence depends on the composition of the substrate subjected to digestion and on the conditions of the anaerobic reactor (pH, temperature, organic load, hydraulic time of residence etc).