Cascaded valorization of food waste using bioconversions as core processes

Abstract

As opposed to common practices such as composting, landfilling and incineration, advanced food waste (FW) valorization strategies are more appealing from the practical, economic and sustainability viewpoints as these can generate multiple products from a single feedstock by taking a biorefinery approach. This chapter focuses on a cascade-type valorization approach for maximal exploitation of FW in which the residues obtained in one step serve as raw material in the following using bioconversions as core processes. This concept respects the marketable product value and comprises the following stages: (1) characterization of biomass to detect more valuable products; (2) extraction of the high-value compounds; (3) bioconversions of FW to chemicals using enzyme, fermentation or bioelectrochemical technology; and (4) conversion of the residue to feed or energy. The state-of-the art of such a biorefinery is presented. The potential of advanced valorization practices is illustrated using several case studies, and the challenges that each technology poses are addressed.