The waste generated by the fishery industry, often regarded merely as refuse, may in fact conceal significant nutritional, environmental and economic value. This discovery comes from a research team at the University of Aveiro (UA), which includes researchers from the Centre for Environmental and Marine Studies (CESAM), who analysed two by-products from the processing of Cape hake (Merluccius capensis): trimmings (head and tail, usually discarded) and leftovers resulting from cutting and filleting processes.
The study, published in the journal Applied Food Research, was authored by researchers Tiago Sousa, Ricardo Calado and Rosário Domingues, from CESAM/Department of Chemistry. In addition to the Department of Biology, the Mass Spectrometry Centre and the Associated Laboratory for Green Chemistry (LAQV) of the Chemistry and Technology Network (REQUIMTE) at UA, the work also involved collaboration with the Vasco da Gama University School, the University of Perugia (Italy), the Portuguese Institute for the Sea and Atmosphere, and the University of Porto.
The study revealed that these materials are rich in bioactive lipids with potential applications in the food, pharmaceutical and cosmetic sectors.
Advanced chemical analysis techniques were used to thoroughly characterise the lipids present in these by-products. The results show that, although both are valuable sources of beneficial compounds, they exhibit distinct lipid profiles.
Fish leftovers resulting from cutting and filleting processes were found to contain higher amounts of ash, proteins and total lipids, as well as higher levels of certain fatty acids, such as palmitic acid and oleic acid. Trimmings, on the other hand, stood out for their greater abundance of phospholipids, particularly phosphatidylcholines, molecules essential for cell structure and with multiple industrial applications.
Despite these differences, researcher João Monteiro points out that both by-products presented similar amounts of marine phospholipids and omega-3-rich phospholipids, including EPA and DHA, which are well known for their benefits to cardiovascular and brain health. The scientist also notes that lipid extracts from both demonstrated significant anti-inflammatory activity in laboratory assays.
Cape hake serves as a case study, but the concept is far broader, the researcher explains, adding that marine species with similar lipid profiles—namely other lean or semi-fat fish rich in omega-3—also generate large volumes of by-products during industrial processing.
One of the most promising aspects of the study is the potential of these marine lipids as an alternative to traditional lecithins, which are generally obtained from soy or eggs. Lecithins are widely used as emulsifiers and stabilisers in the food industry, but there is growing demand for natural, sustainable ingredients with additional bioactive properties.
In this context, phospholipids extracted from Cape hake by-products could be used in the development of functional foods and nutritional supplements, responding to new consumer demands while simultaneously promoting the valorisation of marine resources that have so far been underutilised.
The valorisation of these residues also represents an opportunity to make the fishery industry more sustainable. By transforming by-products into high value-added raw materials, it is possible to reduce waste, increase production efficiency and promote a circular economy within the fisheries sector.
Beyond the food sector, the identified compounds may also find applications in nutraceutical, pharmaceutical and cosmeceutical products, due to their bioactive properties, particularly their anti-inflammatory effects.
The researchers argue that future studies should focus on optimising extraction and purification methods for these lipids, in order to maximise their recovery and fully explore their functional potential.
This study is part of a broader effort to valorise marine resources, developed within the framework of the Blue Bioeconomy Pact project, funded by PRR funds (Next Generation EU programme), which aims to promote innovation and sustainability in the fish industry. In particular, the integration of this work into the project’s transversal platform for the valorisation of by-products reflects the ambition to create scientifically robust solutions that can be effectively transferred to the productive sector, contributing to more efficient resource use, waste reduction and increased economic value generation along the value chain.
Original News in:UA News, 26th january 2026