Evaluating CO₂-derived single-cell protein for sustainable fish feed
The ultimate goal of this project was to transform food production and supply chains by creating animal feed from carbon dioxide and hydrogen gases.
Project team
Partners: Deep Branch Biotechnology – now Aerbio, University of Nottingham, Nottingham Trent University, University of Edinburgh, University of Stirling's Institute of Aquaculture, AB Agri, Sainsbury’s Supermarkets, BioMar, Drax Corporate
Funders: Innovate UK’s Industrial Strategy Challenge Fund (ISCF) - transforming food production, SAIC
Impact
The introduction of single cell protein into aquafeed formulations stands to improve the cost-effectiveness and sustainability of UK aquaculture. The use of a domestically produced, non-GM protein source reduces dependency on imported fish meal and vegetable meal, while simultaneously supporting the bioremediation of CO₂ emissions.
£494,590
Total value
BACKGROUND
As the fastest-growing sector in global food production, aquaculture plays a pivotal role in ensuring future food security. Within this context, the UK salmon farming sector is poised for substantial growth. However, this expansion must be underpinned by sustainable practices. Chief among them, the need to reduce the reliance on marine-derived ingredients such as fish meal (FM) and fish oil in aquafeeds.
Due to regulatory constraints and public perception in the EU, the use of terrestrial animal by-products in aquafeeds is limited. As a result, vegetable meals (VM) have become the main alternative to FM. Yet, VM presents several challenges, including an imbalanced amino acid profile, potential antinutritional factors, competition with terrestrial livestock feed markets, and environmental concerns such as deforestation. These limitations underscore the urgent need for alternative, sustainable sources of protein.
Single-cell protein (SCP) offers a promising solution. Produced from microbial biomass, SCP can be nutritionally tailored to meet the specific requirements of aquaculture species, making it a strong candidate to replace conventional protein inputs in feed formulations.
This project, led by Aerbio (formerly Deep Branch Biotechnology), aimed to evaluate and validate a novel SCP produced from industrial CO2 emissions with an amino acid profile tailored as a sustainable ingredient for aquafeeds. The research was conducted in collaboration with academic partners from the University of Nottingham, Nottingham Trent University, University of Edinburgh, and University of Stirling’s Institute of Aquaculture.
The ultimate goal of the project was to transform food production and supply chains by creating animal feed from carbon dioxide and hydrogen gases.
AIMS
The project set out to assess the feasibility and performance of SCP as a protein source in feeds for Atlantic salmon and poultry. The specific objectives were:
- To assess the effects of substituting FM and VM with SCP in salmon diets on growth, feed efficiency, fish health, welfare, and nutritional quality.
- To determine the digestibility of SCP in Atlantic salmon by calculating the apparent digestibility coefficients for lipids, proteins, fatty acids, and amino acids.
- To evaluate the transcriptomic responses of salmon to SCP inclusion by analysing changes in metabolically active tissues, specifically the liver and pyloric caeca.
- To investigate how SCP-based diets affect the gut microbiota of salmon parr using 16S rRNA gene amplicon sequencing (Illumina MiSeq platform).
OVERVIEW
The research team comprised leading experts with a strong international reputation and a proven record of accomplishment in aquaculture science. Their involvement ensured rigorous methodology and facilitated broad dissemination of results through conferences and publications. While the project was end-user focused, its outcomes will contribute significantly to biological research, especially in species where genomic resources are underdeveloped, such as shellfish and crustaceans.
A 12-week feeding trial with freshwater parr had been planned but was not in the end undertaken. Instead, a small digestibility trial completed with SalmoSim; a spin-out company created on the basis of a previous SAIC-funded research project.
IMPACT
The introduction of SCP into aquafeed formulations stands to improve the cost-effectiveness and sustainability of UK aquaculture. The use of a domestically produced, non-GM protein source reduces dependency on imported FM and VM, while simultaneously supporting the bioremediation of CO₂ emissions. The UK aquaculture sector will be the primary economic beneficiary, with broader applicability in major salmon-producing countries such as Norway, Chile, and Tasmania.
The project offered proof of concept for SCP as a major ingredient in aquafeeds and generated novel datasets on fish nutrition, digestibility, molecular biology, and microbiome interactions. These insights will benefit the wider scientific community and inform future research directions.
Production and commercialisation
The project has now taken another big step forward with the opening of its first pilot facility for Proton production. The facility is based in the Netherlands at the Brightlands Chemelot Campus, a hub for circular chemistry and chemical processes.
The opening of Aerbio’s pilot facility will allow larger feed trials to begin, with an initial 200kg of Proton being produced per month. The pilot facility will help the company determine how best to integrate itself into the food chain, with the Proton it produces being used in the assessment and development of several applications, including in the REACT-FIRST project.
Engineering work is also already being conducted on an upcoming ‘Market Launch Facility’, which will have the capacity to produce 250 tonnes of Proton per annum. Subsequent commercial sites are expected to each produce 100,000 tonnes of Proton per year.
Additional information