Unlocking the Potential of Sea Bass Skin: Characterization of Gelatin and Edible Gelatin Films

This research focused on the extraction of gelatin from the skin of European sea bass (Dicentrarchus labrax) to engineer edible films, comparing their functional properties against standard bovine and fish-derived commercial gelatins. Structural evaluation via Scanning Electron Microscopy (SEM) showed a typical gelatinous morphology, defined by a network of disordered, interconnected filaments. From a biochemical perspective, the extracted material was protein-rich (90.93%), with low levels of moisture (8.11%), ash (0.31%), and lipids (0.13%). Amino acid profiling confirmed a glycine-heavy composition (27.27%) and an imino acid content of 18.71%, contributing to a measured gel strength of 189.5 g. Furthermore, FTIR spectroscopy validated the presence of primary amide bands (A, B, I, II, and III), mirroring the spectral fingerprints of established commercial standards. The resulting glycerol-plasticized films demonstrated robust mechanical performance, characterized by a tensile strength of 6.53 MPa and an elongation at break of 94.55% at a thickness of 0.14 mm. These results confirm that sea bass skin serves as an effective biopolymer matrix for creating stable, functional packaging. This study highlights the viability of upcycling marine by-products as high-performance, sustainable alternatives to mammalian-based materials in the production of bio-packaging.