Review of food waste valorization technologies: A sustainable approach to resource recovery and utilization

Food waste (FW) has emerged as one of the most pressing global challenges, with vast quantities generated throughout the supply chain. Conventional disposal practices such as open dumping, burning, and landfilling pose significant social, economic, and environmental risks. Currently, approximately one-third of all food produced globally (around 1.6 billion tons) is wasted each year, resulting in an estimated $1.2 trillion in economic losses. Owing to its high carbon content and biodegradable nature, FW presents a valuable opportunity for energy recovery, offering a viable alternative to non-renewable energy sources such as crude oil and coal. Valorizing food waste not only contributes to renewable energy generation but also helps mitigate major environmental issues, including greenhouse gas (GHG) emissions. This review explores emerging trends in food waste valorization (FWV) through thermochemical, biochemical, and chemical conversion methods. It emphasizes the latest advancements and research initiatives dedicated to enabling industrial-scale deployment of these technologies. Special attention is given to the production of value-added products, including bio-based chemicals, enzymes, fertilizers, biochar, biodegradable plastics, renewable natural gas (RNG), and biohydrogen, derived from food waste streams. Additionally, the review considers biomass valorization from other sources, such as agricultural residues, as part of a broader circular bioeconomy strategy. This review also highlights the emerging potential of artificial intelligence (AI), machine learning (ML), and the Internet of Things (IoT) in optimizing and valorizing FW management processes. The paper advocates FWV strategies that are holistic, socially equitable, economically viable, and environmentally sound, aligning with the principles of sustainable development.