Greek biotech firm Solmeyea has pioneered a two-step process for converting CO2 into a feedstock to grow protein-rich microalgae ingredients a thousand times faster than would be possible using plants alone.
Numerous studies have demonstrated the potential of microalgae as an alternative protein. Not only are microalgae an excellent source of protein, they also contain antioxidants, fibre, omega-3, vitamins and minerals, and have a far lower environmental footprint than animal-derived proteins.
There are a number of startups emerging in this field, including Greek company Solmeyea, which has succeeded in producing functional protein ingredients from microalgae, using CO2 off-gases from industry as a feedstock for the fermentation.
This innovation, born out of a thesis project carried out by engineering graduate Vasilis Stenos, earned the company a place as a finalist in the Most innovative plant-based or alternative ingredient category of the 2024 Fi Startup Challenge.
It was winning second prize at the Columbia Venture Competition that originally gave Stenos confidence that his concept might have mileage as a business. At that point in time there was just one part to the technology: a bioconversion process for transforming CO2 off-gases into a carbon-neutral feedstock to replace glucose in fermentation processes.
The jigsaw was completed when, two years later, biotech engineer Diego Grumbach joined the venture, contributing to the development of a process for cultivating microalgae biomass that could be used as protein-rich food ingredients.
“Today, we have our patented technology, which is a two-step fermentation process for converting CO2 into a carbon feed that is consequently fed into our microalgae culture. Our non-GMO, tasteless, and colourless proprietary microalgae strains are grown on the carbon-negative feed and collected as protein powder that can be directly incorporated into food,” Harshni Selvaraj, head of downstream at Solmeyea, told this publication.
Through this process, 6kg of CO2 can be converted into 1kg of protein. Even when the emissions related to the process are taken into account, the final carbon footprint is still negative, utilising 2.5g of CO2 per kilo of protein, said Selvaraj.
“Put simply, for every kilo of dried biomass Solmeyea produces, we block or absorb 2.5kg of CO2,” she noted.
The two-step process sets Solmeyea apart from the competition, whose technologies stop at a single-step gas fermentation process, Selvaraj explained.
“We are not only a gas fermentation company producing feed or biochemicals. We go a step further and replace the import of glucose by transferring the carbon source for the microalgae fermentation,” she said.
Another point of difference is that the outcome of Solmeyea’s process is microalgae biomass derived from a proprietary non-GMO white microalgae strain. It is, therefore, an ingredient that is considered safe by the European Food Safety Authority (EFSA) and the US Food and Drug Administration (FDA), as opposed to an unclassified microbe that would be considered a novel food in the EU, for example.
“Our microalgae biomass is not considered [a] novel food and it has GRAS [Generally Recognised as Safe] status, like spirulina and chlorella. Microalgae – especially chlorella – are not a novelty in food production, as they have been consumed historically in Asia, the EU, and the US,” noted
Selvaraj.
This not only satisfies the regulators, but also helps with market acceptance, she explained.
“Customers have a very positive perception of microalgae-based food ingredients and end products compared to bacteria-based potential food products that people are reluctant to even try.”
Essentially, Solmeyea is emulating the natural process by which microalgae grows and accelerating it.
“In the wild, microalgae absorb CO2 and utilise this as their natural growth substrate – they need carbon for growth. We are taking that same microalgae and, instead of cultivating it traditionally, relying on photosynthesis in open ponds, we are using CO2 as an input for our fermentation, which makes the process 30 times more efficient,” said Selvaraj.
Solmeyea says its microalgae biomass has a 40 per cent protein content, a full amino acid profile, a protein digestibility corrected amino acid score (PDCAAS) close to one, and an essential amino acid percentage that is comparable to egg protein. It also has a fibre content of over 15%, and more than 45% of the total fat is poly-unsaturated fatty acids (PUFAs).
In addition, it is colourless (white) with a neutral taste similar to milk proteins. These properties make it easier to work with than other plant-based proteins, such as soy and pea. From a functionality perspective, it shows potential for reducing fat levels and eliminating stabilising agents in recipes.
Recently, Solmeyea took part in the MISTA Growth Hack, a startup acceleration and incubation programme founded by Givaudan, Danone, Mars, and Ingredion. As part of this programme, it developed a microalgae-based yoghurt prototype that showcased the ingredient’s functionality.
“All the functional properties came from the microalgae biomass itself, without additional functional ingredients such as stabilising starch,” said Selvaraj. “Our microalgae provided a source of protein and fibre, as well as a stabilising and emulsification effect.”
In another application example, Solmeyea replaced the eggs in a brownie with its microalgae, resulting in a high protein, vegan recipe. It has also tested the ingredient in plant-based steaks, tuna and cheese.
“The biggest potential is in alternative protein and plant-based sectors as the search for good non-animal protein is a never-ending story,” said Selvaraj.
Through its demo facility, the company has proven its technology for industrialization – producing more than 30 tons a year whilst using 120 tons of CO2. The next step, thanks to the European Innovation Council’s co-investment, is to build its first commercial facility, which is scheduled to be operational by the end of 2026, with capacity for converting 10,000 tons of CO2 into more than 2,200 tons of protein annually.
“Our cost of production is expected to be below €5 per kg for the first protein worldwide made from CO2 that can be sold in the EU and the USA,” said Selvaraj.
