Vázquez Álvarez, José AntonioComesaña Fernández, SaraSoengas Fernández, José LuisPérez Rodríguez, MontseBermúdez Pose, RobertoRotllant Moragas, JosepValcárcel Barros, Jesús2026-01-272026-01-272024-08-20José Antonio Vázquez, Sara Comesaña, José Luis Soengas, Montse Pérez, Roberto Bermúdez, Josep Rotllant, Jesus Valcarcel, Optimal and sustainable production of tailored fish protein hydrolysates from tuna canning wastes and discarded blue whiting: Effect of protein molecular weight on chemical and bioactive properties, Science of The Total Environment, Volume 939, 2024, 173461, ISSN 0048-9697, https://doi.org/10.1016/j.scitotenv.2024.173461https://hdl.handle.net/10347/45448This study evaluates the optimal and sustainable production of tailored fish protein hydrolysates obtained from tuna canning by-products and discarded blue whiting, focusing on the influence of protein molecular weight on their chemical composition and bioactive properties. By combining valorization of fishery wastes with controlled hydrolysis strategies, the work demonstrates how molecular weight distribution modulates functional and bioactive characteristics, supporting the development of high-value, sustainable ingredients for aquafeed and food applicationsThousands tons of discards of blue whiting (BW) and tuna heads (YT) by-products are generated each year in Europe. BW is the species most discarded by European fishing fleet and, in some canning factories, YT are processed for the retrieval of oil rich in omega-3, but producing a huge amount of solid remains and effluents disposal as wastes. The development of optimal and sustainable processes for both substrates is mandatory in order to reach clean solutions under the circular economy precepts. This work focused on the mathematical optimization of the production of tailored fish protein hydrolysates (FPH), from blue whiting and tuna residues, in terms of controlling average molecular weights (Mw) of proteins. For the modeling of the protein depolymerization time-course, a pseudo-mechanistic model was used, which combined a reaction mechanistic equation affected, in the kinetic parameters, by two non-lineal equations (a first-order kinetic and like-Weibull formulae). In all situations, experimental data were accurately simulated by that model achieving R2 values higher than 0.96. The validity of the experimental conditions obtained from modeling were confirmed performing productions of FPH at scale of 5 L-reactor, without pH-control in most of cases, at the different ranges of Mw selected (1–2 kDa, 2–5 kDa and 5–10 kDa). The results showed that FPH from BW with lower Mw led to a remarkable yield of production (12 % w/w of substrate), largest protein contents (77 % w/w of BW hydrolysate), greatest in vitro digestibility (>95 %), highest essential amino acid presence (43 %) and the best antioxidant (DPPH = 62 %) and antihypertensive (IC50-ACE = 80 mg/L) properties. Our results prove that the proposed procedure to produce sustainable FPH, with specific Mw characterisitics, could be extended to other fish waste substrates. Tailored FPH may have the potential to serve as valuable ingredients for functional foods and high-quality aquaculture feedengAttribution-NonCommercial 4.0 Internationalhttp://creativecommons.org/licenses/by-nc/4.0/Fish protein hydrolysatesBlue whiting discardsTuna by-productsProtein molecular weightMathematical modelingBioactivesSustainabilityInvestigaciónjournal article10.1016/j.scitotenv.2024.1734611879-1026open access