Sustainability assessment of collagen extraction from fish skins: A comparative life cycle assessment of conventional and NADES-enhanced processes

Collagen from blue shark skins offers a promising solution to utilize fishery by-products, reducing waste and improving resource efficiency. This study develops green chemistry-based extraction processes to minimize reliance on traditional chemical methods and lower environmental impacts , prioritizing sustainability and circularity . Two methods for collagen extraction are compared: a conventional alkaline-acid process and an innovative approach using natural deep eutectic solvents (NADES). Process simulations were conducted using SuperPro Designer software for the annual production of 500 kg of pure extracted collagen, followed by life cycle assessment (LCA) using SimaPro software and the Ecoinvent database , applying the Environmental Footprint (EF) method. For 1 kg of pure marine collagen from fish skin residues, defined as the Functional Unit, the conventional approach yielded a single-score impact of 48.1 mPt, while the NADES method achieved 41.5 mPt. Subsystem analysis reveals that, in the conventional method, the extraction and purification stages account for most of the environmental impact (43 % and 45 %, respectively). In contrast, the NADES method attributed 94 % of its total environmental impact to extraction stage, primarily due to NADES component production (citric acid, xylitol). Uncertainty analysis suggests that conclusions regarding impact reduction should be drawn with caution due to the environmental impact variability of considered inputs. Nevertheless, the mathematical model underscores the potential of the NADES method to reduce the environmental impact and promote more sustainable bioprocessing . This work offers valuable insights into the life cycle assessment of large-scale bioprocesses using green chemistry, providing a tool for optimization and environmental impact screening. • Purified collagen extraction simulated for a traditional and an enhanced method. • Input demand was used to estimate the environmental impacts of both processes. • LCA shows a 14 % reduction in comparison to traditional process impact. • NADES constituents’ production significantly impact NADES extraction process. • Solid waste and wastewater characterization suggests waste valorization potential.