Vuoristo started working for NMBU and Foods of Norway in September 2015. Together with colleagues, her first task was to develop the small-scale biorefinery, consisting of four 2.5 liter fermenters.

“I am trained as a molecular biologist and worked with small fermenters for my PhD degree in metabolic engineering of E.coli. Establishing this functional lab-scale pilot has been a learning process. The learning curve has been steep, but interesting”, Vuoristo says.

Opening the door to the lab, she smiles and says:

“Come in, meet my four ‘babies’ – the four fermenters”.

Scaling up screening

With the new equipment installed, Vuoristo and her Foods of Norway colleague, PhD student  David Lapeña Gomez, will start running the first trial in the small-scale biorefinery in a couple of weeks.

“We are currently screening yeasts that we have received from Foods of Norway’s partners. This means that we can easily look for the yeasts that we think are interesting for feed production. The new fermenters enable us to scale up the screening and develop a single cell production, in this case from yeast, for feed trials”, Gomez explains.

To have a sufficiently high nutritional value for feed, the yeast should have high protein content and quality. If we can be achieve this, the potential for yeast as a protein source is  promising:

According to NMBU researcher Liv Torunn Mydland, a researcher at NMBU, a field with 500 kg of soybean plants produces about 10 kg of protein a’ day. In a fermenter, 500 kg of yeast cells growing on sugar streams can turn into 50 tons of protein a’ day.

Searching for the ideal fermentation conditions

A major task is  to determine the optimal fermentation medium for yeast production for these novel feeds. To do this, the researchers need to add nitrogen sources and sugar streams. Vuoristo and Gomez have received sugar streams from Foods of Norway’s partner Borregaard and meat and fish by-products from Norilia and Nutrimar, respectively. By yeast fermentation, the researchers aim at converting these non-edible biomass products into great feed.

The substrates from Norilia and Nutrimar might also contain other valuable components, such as lipids, which are relevant both for feed and other applications.

“Right now, our focus is on the proteins. At a later stage, however, we will look for the potential to also produce other high-value products”, Gomez says.