Characterization of the Thermal Stability of Type I Collagen Extracted From Atlantic Cod ( Gadus morhua ) Skin

Collagen, one of the most abundant structural proteins in vertebrates, is an important compound in biomaterials and biomedicine, with applications in musculoskeletal regeneration and tissue engineering, but also food, packaging, and cosmetics. Its excellent biocompatibility, water‐binding capacity, and low cytotoxicity make it highly suitable for these purposes. The chemical structure and functional behavior of extracted collagen vary with its biological source (terrestrial, marine, or recombinant microbial systems) and are strongly influenced by the extraction method, which determines its structural integrity. This work studies the thermal stability of Type I collagen extracted from salted codfish skin at 4°C and subjected to thermal treatment at temperatures from 20°C to 80°C for 72 h. Structural stability and conformational changes were analyzed by UV–Vis, SDS–PAGE, XRD, CD, and FTIR. Results revealed that collagen retained its triple‐helical structure up to 20°C, showing no significant deviation from the sample extracted at 4°C. Above 20°C, structural changes are observed, attaining their maximum at 80°C. These results provide insights into the thermal stability of marine collagen and suggest that controlled extraction at room temperature can maintain its structural integrity that can be important toward a sustainable valorization of waste marine biomass.