Sustainable Valorization of Plant-Derived Agri-Food Side-Streams Through Fungal Biorefinery: Supporting Bioeconomy Strategy

The rapid expansion of agricultural and agri-food production has generated substantial volumes of byproducts and side-streams rich in organic matter. Despite their potential, these residues remain largely underutilized, contributing to environmental pressures and constraining the economic sustainability of food systems. Filamentous fungi, with a long history of assimilating agri-food side-streams (AFS), offer a promising solution by enabling the conversion of organic-rich side-streams into nutrient-dense fungal biomass suitable for novel food and feed applications. This review synthesizes recent advances in the use of filamentous fungi to valorize AFS into value-added, bio-based products and compounds relevant to food and feed sectors. A comprehensive analysis of 268 peer-reviewed research articles was conducted to identify prevailing trends, technological developments, and key factors influencing the bioconversion of AFS. Emphasis is placed on bioprocessing strategies for tproducing commercially relevant fungal-derived ingredients, including proteins, enzymes, polysaccharides, lipids, and bioactive compounds. Innovative approaches aimed at improving production efficiency and addressing industrial-scale challenges, including fungal biomass recovery, downstream processing, and functional compound extraction, are also discussed. The review highlights significant opportunities for innovation in upcycling AFS through integrated fungal biorefinery platforms. Advancements in fungal bioprocessing support the development of sustainable, cost-effective, and environmentally friendly food and feed products within a circular bioeconomy framework, emphasizing both ecological and economic benefits.