"This mussel powder may be the feed of the future," said the Norwegian Institute of Marine Research.
Photo: Pauline Paolantonacci / Norwegian Institute of Marine Research.
Can blue mussels be a viable ingredient in salmon feed? Can they become Norway's solution for making salmon feed more sustainable? This is what the researchers in the 'Mussel Up' project will investigate. Led by the Norwegian Institute of Marine Research (IMR), it is also a collaboration with Nofima, Lerøy, NORCE, and the University of Stirling.
"We want to find out whether blue mussels are safe and nutritious for salmon, and whether processing preserves the nutrients," said Ikram Belghit, the marine scientist leading the project.
Its ultimate goal is to produce high-quality mussel meal as cost-effectively and sustainably as possible, but to do so, researchers must first find out whether blue mussel production can be scaled up, whether blue mussels can truly be used as a new ingredient in Atlantic salmon feed, and whether all of this is economically viable.
As the Norwegian Institute of Marine Research explained, "the project model the production capacity and ecosystem services of blue mussel aquaculture along the coast; identify the optimal method for producing high-quality blue mussel products; conduct feed trials both in vivo and in vitro; and assess the sustainability and economic viability of new feed ingredients."
By 2034, all aquaculture feed in Norway has to come from sustainable sources, and the share of Norwegian-produced ingredients must increase from just 8% today to 25%. Thus, back in May 2024, another study by the Norwegian Institute of Marine Research itself indicated that Norway needs more locally sourced ingredients for fish feed.
"To increase the proportion of Norwegian ingredients, we must also consider what we can cultivate," said researcher Sofie Remø at the time. Under this premise, during three feeding trials, researchers fed salmon with mussels and sugar kelp, considering both to be good options because they are low-trophic and can be cultivated along the coast in Norway. However, the Institute also explained then that fish feed requires a lot of fat and protein, absent in kelp, while mussels have more nutrients.
The 'Mussel Up' project now emphasizes the same idea that mussels are a so-called low-trophic species, meaning that they are at the bottom of the food chain, easy to farm in Norway, and rich in nutrients.
"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," explained Ikram Belghit. "In addition, they are nutrient-rich and readily available locally. That makes them a strong candidate for more sustainable feed production," she continued.
Moreover, the researcher added that the long coastline in Norway means that the country perhaps has "the greatest potential for blue mussel production in Europe."
"Today, most aquaculture feed ingredients are imported," said Belghit. "That's why we're investigating the possibility of using blue mussels in salmon feed." The final goal is to increase local feed production and reduce environmental impact.
As mentioned above, this is not the first time that the Norwegian Institute of Marine Research has conducted a study including blue mussels as a potential novel ingredient for aquafeed. However, as the Institute has now pointed out, mussel production poses certain challenges.
Over two years, various methods have been tested to make the best possible use of fresh mussel meat. Researchers at Nofima’s feed technology centre have produced different types of blue mussel products, which IMR researchers have tested for use in feed.
"Blue mussels have a high water content, which makes preservation and processing challenging," explained senior researcher at Nofima, Tor Andreas Samuelsen. "But we have now identified the best way to produce it."
According to the Norwegian Institute of Marine Research, some processing is necessary to preserve the product and enable its use in fish feed. However, excessive processing can reduce product quality and often increases energy consumption.
As said, the goal is to produce high-quality mussel meal in the most cost-effective and sustainable way possible, so that it can be used as a sustainable ingredient in aquaculture feed, but also to check how this feed affects the fish's health. To this end, the final step of the project is to test the new feed on salmon.
"We will study how it affects growth, health, and welfare in the fish. This is essential in determining whether blue mussels can be used commercially," concluded the project leader, the marine scientist Ikram Belghit.
