Protein Extraction from Food Waste

Food loss and waste (FLW) pose significant challenges to global food systems, contributing to environmental degradation and economic inefficiencies. Valorizing protein-rich agri-food residues offers a strategic solution to mitigate these impacts and promote a circular bioeconomy. Conventional protein extraction methods, such as solvent precipitation or alkaline extraction, are widely used but are constrained by harsh processing conditions, reduced yields, and protein denaturation. In contrast, novel non-thermal techniques, including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pulsed electric field (PEF), high hydrostatic pressure (HHP), ohmic heating (OH), and deep eutectic solvents (DESs), have emerged as sustainable alternatives. These methods operate under milder conditions, enhancing protein recovery, preserving structural integrity, and reducing environmental footprints. This chapter critically evaluates conventional and emerging novel extraction approaches, highlighting their mechanisms, operational efficiencies, and techno-economic viability.