By now, we’ve all heard that eating meat is not good for the planet. The industry produces a lot of emissions and uses up a lot of environmental resources. But realistically, the only way most people will reduce their consumption anytime soon is if they have palatable alternatives that replicate the “mouthfeel” of meat. Such alternatives do exist — but they’re not perfect. And, perhaps more importantly, they’re also hard to produce at scale, which means we need more alternatives.

But what if we have an unexpected ally in this struggle: cyanobacteria?

Milking cyanobacteria

Cyanobacteria is also called “blue-green” algae — which is a misleading name because they’re not related to algae at all. They’re bacteria that have the ability to photosynthesize. In fact, they may be the first creatures that developed photosynthesis on Earth, some 3.8 billion years ago. In recent years, scientists have become more and more interested in cyanobacteria for use as a biomaterial or in various renewable technologies. They’ve even been proposed as alternatives to wood or cement, as an alternative for plastics, or as a CO2 sink. But their potential as a protein source has been less explored.

The key aspect in replicating the texture and taste of meat lies in protein. Contrary to popular belief, meat isn’t the only natural source of protein; not at all. Plenty of plants and algae also produce protein (some quite a lot), but the types of protein don’t have the same structure as meat. This means they don’t taste the same and don’t have the same texture either.

Cyanobacteria also doesn’t normally produce that type of protein. But researchers engineered cyanobacteria that has been coerced to produce it.

“Cyanobacteria, also known as blue-green algae, are living organisms that we have been able to get to produce a protein that they don’t naturally produce. The particularly exciting thing here is that the protein is formed in fibrous strands which somewhat resemble meat fibers. And, it might be possible to use these fibres in plant-based meat, cheese or some other new type of food for which we are after a particular texture,” says Professor Poul Erik Jensen of the Department of Food Science.

Hijacking genetics

The process is strikingly futuristic. The researchers hijack the cyanobacteria and insert foreign genes into it, basically using it as a host organism. Then, inside the cell, the protein starts to re-arrange itself into tiny threads (nanofibers). The process requires minimal processing — the cyanobacteria basically do all the work.

“I’m a humble guy from the countryside who rarely throws his arms into the air, but being able to manipulate a living organism to produce a new kind of protein which organizes itself into threads is rarely seen to this extent — and it is very promising. Also, because it is an organism that can easily be grown sustainably, as it survives on water, atmospheric CO2 and solar rays. This result gives cyanobacteria even greater potential as a sustainable ingredient,” says an enthusiastic Poul Erik Jensen, who heads a research group specializing in plant-based food and plant biochemistry.

So instead of going for the more established approach, which involves taking an existing protein and processing it to make it look more meatlike, this approach basically generates meat-like protein all from the get-go.

“If we can utilize the entire cyanobacterium in foodstuffs, and not just the protein fibers, it will minimize the amount of processing needed. In food research, we seek to avoid too much processing as it compromises the nutritional value of an ingredient and also uses an awful lot of energy,” says Jensen.

Tomorrow’s cattle

Ironically, the fundamental of the process isn’t all that different from what we’re already doing with cows. Cows have also been hijacked, though not as directly. Cows nowadays produce much more meat and dairy than they used to because we’ve selected them for this. So, we used selective breeding instead of direct hijacking.

Researchers already envision a world in which cyanobacteria would become the “cows of the future”.

“We need to refine these organisms to produce more protein fibres, and in doing so, ‘hijack’ the cyanobacteria to work for us. It’s a bit like dairy cows, which we’ve hijacked to produce an insane amount of milk for us. Except here, we avoid any ethical considerations regarding animal welfare. We won’t reach our goal tomorrow because of a few metabolic challenges in the organism that we must learn to tackle. But we’re already in the process and I am certain that we can succeed,” says Poul Erik Jensen, adding:

“If so, this is the ultimate way to make protein.”

There’s another important bonus for this approach. Cyanobacteria is already grown industrially. You might have heard of spirulina — a so-called “superfood”. That’s actually a cyanobacteria, and the global spirulina market is estimated to be over $1.1 billion by 2030. This production can also be used for protein-producing cyanobacteria.

For now, however, there’s still a long way before we’ll be eating cyanobacteria meat, but the technology is poised to make an important impact. Along with processed plant protein and lab-grown meat, this approach promises to bridge the gap to more sustainable protein consumption and help reduce our global meat consumption.

Journal Reference: Julie A. Z. Zedler, Alexandra M. Schirmacher, David A. Russo, Lorna Hodgson, Emil Gundersen, Annemarie Matthes, Stefanie Frank, Paul Verkade, Poul Erik Jensen. Self-Assembly of Nanofilaments in Cyanobacteria for Protein Co-localization. ACS Nano, 2023; 17 (24): 25279 DOI: 10.1021/acsnano.3c08600