Scientists at the Norwegian Institute of Marine Research (IMR) have launched a study to determine whether blue mussel can be used as an ingredient in aquaculture feed.
In line with the study, IMR scientists will add blue mussels to salmon feed and study how their inclusion will affect salmon health.
"We want to find out whether blue mussels are safe and nutritious for salmon, and whether processing preserves the nutrients," said IMR scientist and project leader Ikram Belghit.
By 2034, all aquaculture feed in Norway must come from sustainable sources, and the share of Norwegian-produced ingredients must increase from just eight per cent today to 25 per cent.
The goal is to boost local feed production and reduce environmental impact.
"Today, most aquaculture feed ingredients are imported," said Belghit. "That’s why we’re investigating the possibility of using blue mussels in salmon feed."
Blue mussels are a so-called low-trophic species, meaning they sit at the bottom of the food chain.
"Blue mussels are easy to farm, require no advanced technology, take up little space, and naturally remove excess nitrogen, phosphorus, and carbon from the water," Belghit added.
"In addition, they are nutrient-rich and readily available locally. That makes them a strong candidate for more sustainable feed production."
Blue mussel production nevertheless comes with some challenges.
Over the course of two years, researchers have tested several methods to make the best possible use of fresh mussel meat.
Researchers at the feed technology centre of Norwegian food and fisheries science institute Nofima have produced different types of blue mussel products, which researchers at IMR later tested for use in feed.
"Blue mussels have a high water content, which makes preservation and processing challenging," said Nofima senior researcher Tor Andreas Samuelsen. "But we have now identified the best way to produce it."
Some processing is necessary to preserve the product and to enable its use in fish feed. However, excessive processing can reduce product quality and often increases energy consumption.
IMR said the goal is to produce a high-quality meal in the most cost-effective and sustainable way possible.
The final step in the project is to test the new feed on salmon.
"We will study how it affects growth, health, and welfare in the fish," said Belghit. "This is essential in determining whether blue mussels can be used commercially."