Among the VFA valorization options, the use of VFA mixturesas substrate for the microbial production of PHA can be consideredone of the most valuable because it is an efficient way of recoveringresources from wastewater [20,21]. The use of organic residues asa carbon source for PHA production can also reduce costs by up to50% [22]. However, for this purpose, attention must be paid to thecomposition of the VFA because it affects both the efficiency of PHAproduction and the characteristics of the final polymers [23–25].The latter can be predicted to some extent by determining the ratiobetween odd and even VFA [16].