On 22 October 2025, we were pleased to host the first technical webinar of the Circularis BioCluster. It is a collaborative initiative gathering three Horizon Europe projects – VALORISH, ONE EARTH, and PROMISEANG sharing a common goal: valorising animal by-products through innovative biotechnological solutions. In this session, our researchers presented the early scientific results while exploring synergies in the valorisation of animal by-products.
A shared vision: Transforming underutilized biomass into value
The three projects share a common ambition: to turn animal-derived side streams – often treated as waste – into inputs for a circular bioeconomy through biotechnological processes. Despite working on different waste streams, they follow a similar logic:
- identifying high-potential waste materials,
- characterising their composition,
- applying biotechnological processes,
- producing valuable compounds for industrial application.
These routes are supported by computational tools, screening techniques and bioinformatic workflows that enable data-driven optimisation of strains, substrates and processes. By doing so, the projects aim to reduce waste, improve sustainability, and create new circular value chains across agriculture, cosmetics, feed, nutraceuticals, and beyond.
VALORISH: Computational screening for enzymatic valorisation
VALORISH is developing a computationally assisted biorefinery to convert fish processing by-products into high-value products such as fish oils, bioactive peptides, and collagen.
Laurs Oleaga González (Pescanova), Borja Lagoa Costa (Anfaco), and Marta Franco de Benito (Idener) presented the methodology and early results of the research activities of the first half of the project.
The project began with a detailed characterisation of multiple fish by-products (e.g. heads, trimmings, skin, bones). It aims to determine their nutritional content, volume availability and potential for valorisation. Based on these results, the team selected by-products for two main routes:
- Oil extraction
From salmon heads and trout heads, the project uses emerging technologies like supercritical CO₂, subcritical water, and natural deep eutectic solvents (NADES). These sustainable methods allow selective and clean separation of lipids rich in Omega-3 fatty acids (EPA and DHA), suitable for food, cosmetics, and pet food - Proteolytic fermentation
From shrimp, surimi, and hake sawdust, protein-rich materials are converted into bioactive peptides. These are of interest not only for their antimicrobial, antioxidant, and immunomodulatory properties, but also for their functional uses (e.g., emulsification, gelling) in diverse sectors.
The VALORISH approach is supported by a computational simulation. It screens bacterial strains and protein substrates to assess the ability of the microorganism in digesting the target proteins and produce bioactive peptides. Moreover, it also allows a fast and precise selection of candidates. By using enzymatic profiling, metabolic modelling, and bioactivity prediction, this in silico approach has narrowed down the most promising candidates, guiding future lab validations.
ONE EARTH: Circular routes from poultry, dairy and fish by-products
In ONE EARTH, we are working to valorise by-products from three agri-food sectors:poultry, dairy and fish. We plan to transform them into fertilisers, adhesives, feed ingredients and bioactive peptides.
Anna Laura Eusebi (University of Le Marche) and Noura Raddadi (University of Bologna) presented the first technical outcomes of the valorisation activities. They focus on three main routes:
- peptide production from animal by-products,
- cheese whey fermentation for the production of volatile fatty acids,
- the development of analytical and bioinformatics tools to support peptide identification and characterisation.
To valorise keratin-rich by-products like chicken feathers, fish bones, and fish scales three hydrolysis methods – microbial, enzymatic, and chemical – have been used. Each of them offers different advantages in terms of selectivity, sustainability, and scalability.
Microbial hydrolysis led to the selection of bacterial strains from desert and marine environments capable of producing hydrolysates with strong antioxidant and antimicrobial properties. These hydrolysates remained active after heat treatment. They showed no toxicity to skin cells, with active compounds successfully separated by ultrafiltration. In the enzymatic hydrolysis two enzymes – trypsin and papain – were used on pretreated feathers, enabling the production of peptides.
Peptide characterisation methods were set up (e.g., MALDI-TOF MS), and enzyme immobilisation techniques were established. They will be applied for recombinant keratinase(s).
Chemical hydrolysis parameters were optimised for duck feathers, using an analytical tool characterising the peptides. Furthermore, a bioinformatic tool is being developed to identify peptides and track keratin degradation, based on the peptide mass. In addition, further work has been done on developing a tool to selectively hydrolise amide bonds.
While for cheese whey, results from the anaerobic fermentation process have demonstrated the successful production of volatile fatty acids (VFA). These promising outcomes were achieved by identifying optimal conditions for semi-batch fermentation at laboratory scale (TRL 3). An optimised solid–liquid separation process follows the fermentation, allowing the recovery of the solid fraction for pyrolysis into biochar. It is intended for use in fertilisers and soil amendments – while the VFA-rich liquid fraction is directed to downstream bioconversion steps.
These include microalgae cultivation using CO₂-rich effluents and the synthesis of polyunsaturated fatty acids (PUFAs) from their biomass. The process is now set to be scaled-up at pilot level (TRL 5) at the WEEE Lab (Water and Waste Environmental Engineering Lab from Università Politecnica delle Marche). It will mark a significant advancement towards industrial replication of this circular valorisation route.
PROMISEANG: Producing microbial protein from marine biomass
PROMISEANG aims to revalorise underexploited marine by-products – including tuna processing waste (heads, viscera, tails), bivalve shells, cephalopods, and selected macroalgae. Through fermentation it generates sustainable, protein-rich microbial biomass that meets food and feed standards.
The project’s advancements were presented by Celia Costas Sánchez (University of Vigo). She shared the work done to assess the nutritional composition and food safety of various marine by-products. They analyzed elements such as protein, mineral content, and potential contaminants, including safety screening to check for marine biotoxins and heavy metals.
The findings revealed high protein content, confirming their potential as fermentation substrates. Importantly, the food safety assessments showed no detectable marine biotoxins, allowing the viability of these side streams for food and feed applications.
Looking ahead
We look forward to sharing the future results of our project and the cluster projects. We will continue to exchange knowledge, and move together towards a stronger and more integrated bioeconomy in Europe.
This is just a brief summary of our webinar. If you wish to learn more about the technical aspects and results of our research, check the full recording here: https://www.youtube.com/watch?v=5L-c8dk3kGQ&t=2s