Transforming seafood processing residues into a circular blue bioeconomy: modern advances, integrated pathways and...

Global seafood production generates vast quantities of residual biomaterials, including shells, skins, bones, and viscera, often exceeding half of the harvested mass. These heterogeneous residues are rich in proteins, lipids, chitin, collagen, pigments, and minerals, representing valuable biochemical reservoirs. Recent advances in green extraction, enzymatic processing, microbial engineering, and integrated thermo-biochemical conversion have enabled efficient fractionation into diverse product streams. Such cascaded approaches yield bioactive peptides, marine oils, functional polysaccharides, biomaterials, and renewable fuels. This review synthesizes the transition from isolated valorization processes to integrated seafood biorefineries that prioritize sequential recovery, value maximization, and resource efficiency. By reframing seafood residues as strategic feedstocks, it highlights their potential to drive innovation across health, materials, agriculture, and sustainable energy, supporting the development of a circular marine bioeconomy.