This SCP is touted as a sustainable alternative to fishmeal and soy protein concentrate in fish feed.
The experts involved are part of a biotech venture called Enifer Bio, which began life in the startup incubator, Launchpad, run by Finnish technical research organization, VTT.
“Actually, the Finnish Pekilo based process is the longest running single cell production method for feed protein in the world,” Heikki Keskitalo, CTO, Enifer Bio, told us. He has spent years studying the Pekilo process.
Finland and some other countries have long history using Pekilo protein in poultry and pig feed, he reported.
In Finland, in the 1970s, the pulp and paper industry invested heavily to develop a technology to convert side streams from sulphite wood pulping into SCP. The program uncovered a micro-organism, Paecilomyces variotii, capable of producing protein-rich SCP from dilute, heterogeneous and inhibitory organic side streams. After more than 15 years of R&D, the process was taken into industrial use, and operated at two sites, Jämsänkoski and Mänttä, each with an annual production capacity of 10,000 tons. Under the trade name, Pekilo, the mycoprotein product was successfully used in pig and poultry feed formulations for well over a decade, explained Keskitalo.
However, developments in pulp production technology gradually led to the replacement of sulphite pulping with Kraft pulping in Finland. Interest in single cell protein waned and the Mänttä Pekilo plant finally closed its doors in 1992.
The Enifer Bio experts, which have backgrounds in many disciplines from fungal biology to generic engineering to bioprocess engineering and biomass chemistry, are now in the process of reviving and optimizing that SCP production method. “We are looking to improve the process control and oxygen transfer.”
The Pekilo process can leverage cheap, fermentable side streams such as sugars, acetic acid, formic acid, and methanol, said Keskitalo.
Advantages of this SCP production method
Pekilo production is profitable even at the smaller scale, he said. Essentially, the continuous fermentation mode and absence of a separate hydrolysis step ensure high productivity and favorable techno-economics. Energy consumption in the Pekilo process is reduced compared to other SCP manufacturing processes, added the CTO.
The original Pekilo strain was selected through broad screening of hundreds of fungal species. It is very fast growing, it tolerates many inhibitory compounds in side streams, has a good nutritional profile - up to 65% protein and 20% beta-glucan content - and can be efficiently filtered from even very dilute streams, he said.
Moreover, the strain has a history of over 15 years of use in animal feed, stressed Keskitalo.
Enifer Bio is currently in a pre-launch mode. “We are currently negotiating with Finnish venture capitalists to fund the building of our pilot plant [in order to get proof of concept].”
The team expects to start building its first industrial plant in Finland in 2021, using forestry-related side streams.