Branching out: bid to make fish feed from sawdust

Risto Korpinen, who wrote his master’s thesis about making cellulose out of sawdust, is leading a project called MonoCell – High-quality single cell protein for fish feed, according to a report by Kaskas Media journalist Silja Annila.

Finnish sawmills produce 3.3 million cubic metres of sawdust each year. Even though a large part of it is used for pulp and energy production, a substantial amount of it is piling up, unused and finally rotten.

Korpinen, who is attached to Finland's Natural Resources Institute, known as Luke, said: “There has been a lot of discussion about the challenges that food production has to face in the future. That is also one of the reasons why I came up with this idea.”

He added: “In Finland we use a lot of imported feed like soy. The industry is lacking a sustainable domestic option for fish feed.”

Ideal raw material

Korpinen, who has a doctoral degree in science in technology, regards sawdust is an ideal raw material for fish feed because it is not suitable to be eaten as such.

“We could do these same things with potato or corn starch too, but starch can also feed humans. In the US they make bioethanol out of starch, even though there are plenty of people in the world suffering from hunger. It just goes against my morals to use food in fuel production.”

Utilising sawdust in protein production is a sophisticated process that includes several stages, and the aim is for the research to be done this autumn. The team consists of ten researchers from all over Finland. Korpinen will mainly be working on the first stages, as he is the lead researcher and the one conducting the initial experiments. Some of the procedures are fairly familiar to the research team as they have previously been used in other projects.

Serious option

“Everyone in our team has their own task that reflects their expertise. We have food scientists and nutrition experts, for example. At the end, researcher Frans Silvenius will do a life cycle analysis that will tell us how much energy and chemicals have been used in the whole process”, Korpinen said.

Korpinen believes that wood-based protein has a realistic chance of becoming a serious option for fish feed. Pulp mills have the right facilities to develop and use the MonoCell innovation and create new business for themselves.

“Mills could establish protein production units on their properties. They could benefit from the synergy by not just circulating the materials, water and chemicals but also energy, like electricity and steam”, Korpinen says.

At the moment sawdust can be used in making biofuels, for example, but due to Finland’s current energy policies - which subsidises the use of forest chips - it is not profitable to use sawdust as an energy resource.

According to Annila's report, the near future for MonoCell already includes cooperation with an actor who is interested in producing the protein.