Food waste valorisation for a circular bioeconomy: integrating biochemical, thermochemical, and digital technologies with sustainability metrics

Abstract

Food loss and waste (FLW) has emerged as a major global challenge, contributing to resource depletion, greenhouse gas emissions, and food insecurity throughout the agri-food supply chain. Transforming FLW into value-added products offers significant opportunities to advance the circular bioeconomy while improving resource efficiency and environmental sustainability. This review critically synthesizes recent advances in food waste valorisation by integrating biochemical, thermochemical, and integrated biorefinery technologies with sustainability assessment and digital innovations. A PRISMA-guided literature review was conducted using major scientific databases to evaluate food waste valorisation pathways, including anaerobic digestion, fermentation, enzymatic hydrolysis, hydrothermal carbonization, pyrolysis, gasification, and integrated biorefineries. The selected studies were comparatively analysed with respect to feedstock suitability, technology readiness, resource recovery potential, environmental performance, life cycle assessment (LCA), and circular bioeconomy principles. The synthesis indicates that integrated biorefinery systems provide superior resource recovery and product diversification compared with single-technology approaches by simultaneously producing biofuels, biochemicals, biofertilizers, biopolymers, enzymes, and other value-added products. No single technology is universally optimal; rather, technology selection depends on feedstock characteristics, process efficiency, infrastructure availability, economic feasibility, and regional socio-economic conditions. The review further identifies artificial intelligence, the Internet of Things (IoT), and smart monitoring systems as emerging tools for improving waste segregation, process optimization, and traceability. Key barriers to large-scale implementation include inconsistent feedstock quality, limited infrastructure, fragmented regulatory frameworks, market constraints, and inadequate sustainability assessment. This review provides an integrated analytical framework that combines advanced valorisation technologies, sustainability assessment, digital innovations, and circular bioeconomy principles. It identifies key technological and governance gaps, compares major valorisation pathways, and outlines strategic priorities for developing resilient, resource-efficient, and climate-responsive food waste management systems that support sustainable development. Analyses integrated biorefinery approaches for food waste valorisation across agri-food value chains. Assesses thermochemical and biochemical routes for converting food waste into value-added products. Discusses environmental and economic trade-offs in food waste valorisation using LCA-based perspectives. Explores non-conventional green technologies and niche bioproducts from food waste. Identifies barriers and opportunities for scaling sustainable food waste management.