Microalgae | 4 Interesting Ways To Eat Algae

They contain more proteins than steak, and more iron than spinach. They also grow in salt water, double in size everyday, and absorb CO2. Despite all this, algae hasn’t really made it as a dietary product yet. They have a great potential, but do we really want them on our plates?

A green plate of green microalgae radiates health - it’s no wonder why Spirulina smoothies have been a big hit. But traditions are hard to break and we are still just not used to seeing certain products with such a vibrant new green look. So what can be done about it?

Extracting The Green From Algae

Researchers could adjust the colour of the algae, but it’s very complicated: it would require extracting the desired components from the algae and then refining them. The problem here is that this increases the costs, and extracting the colour would also depend on the final product itself. Imogen Foubert, head of the Food & Lipids lab at the Catholic University Leuven (campus Kulak Kortrijk), has done a lot of research into fats in microalgae, and says, “It’s very difficult to strip the fats in green algae of their green colour without also losing certain beneficial qualities. Together with the green pigments, you would also be removing the carotenoids: antioxidants that oxidatively stabilise the fats (giving it a longer shelf life, ed.). For protein applications, decolourising is the easier solution. Because pigments are fat-soluble, they stay behind in the fats when you extract them from the proteins.”

So, what other options are there when preparing algae-infused foods?

1. Eat algae with already-green foods

Image by Roos Mestdagh

Foubert explains an easier option:“choosing specific foods in which the green colour doesn’t stand out. We’re already used to green smoothies, soups or sauces. But green sandwiches or meat products… not so much. My research group once made a type of Plop sausage with algae. It turned out to be really green - although a good marketer could probably still sell something like that.  

A small amount of one or 2% of algae already has a strong impact on the colour of your food. On the other hand, there are also algae that aren’t green, so maybe red microalgae would do better in meat products.”

2. Use spirulina for an aesthetic plate

To seaweed chef Donald Deschagt of Le Homard et La Moule in the Belgian coastal town Bredene, however, the typical Spirulina colour is an asset. “I use Spirulina powder for its nice green colour and as a salt substitute. A dash of Spirulina in a meringue makes it stand out next to the red fruit that I serve it with. I also use it in rolls, seaweed sausage, shrimp crackers, macarons and biscuits.” The amounts that Deschagt uses are too small to cause a distinct Spirulina taste or an extremely bright colour. But his dishes prove that a green touch doesn’t pose any problems for those who are open to new experiences.   

3. Adding flavour with algae

The flavour is a story in itself - algae is actually a very diverse group, hence the enormous diversity in flavours. “Some flavours are a bit grassy, others remind of fish or lobster. It’s a matter of choosing the right combinations. I once had cocktail nuts that were actually tastier with algae powder than without”, Foubert recounts. 

Alexander Mathys, a researcher on microalgae processing at the ETH Zurich, particularly sees potential in heterotrophic algae (which means they don’t photosynthesize), as they do not have a green colour from lack of photosynthesizing. “In green algae, the flavour poses a bigger challenge than in heterotrophic algae, which we can season with natural flavours or herbs. After all, we seldom consume pure, unseasoned ingredients. So let’s get creative.” 

However, Fouberts notes that “those heterotrophic algae do come with a drawback, they don’t contain the carotenoids that are found in green algae, which makes them more susceptible to deterioration by oxygen.”

4. Adding texture to algae

Image by Roos Mestdagh

Algae powder alone will not help to meet our protein needs. Siegfried Vlaeminck, who researches sustainable microbial technologies at the University of Antwerp shares that, “We have to go from supplement to ingredient, which will require creativity and food technology. Most people will not be that quick to start using powders or pellets, so it’s important to give the algae proteins a certain texture. Think for example of ready-to-cook plant-based burgers, mince or chicken nuggets. These proteins are isolated from soy or peas and then texturized. A commonly used method for this is extrusion.”

Extrusion is a technique that uses screws, heat and pressure to transform the algae proteins into a solid mass of meat-like fibres. Mathys and his colleagues experimented with this technique: “In our experiments, extrusion didn’t work quite well with pure algae proteins. But, mixing it with other proteins, like legumes for example, gave the best results in terms of nutritional value, texture and other organoleptic properties (flavour, odour, look, etc.).” 

A mix of 60% soy and 30% algae proved to be ideal in their experiment. The specific type of algae used by the team produced a final product containing significantly more vitamin B1, B2 and E compared to another meat substitute made only of soy. “We used a yellow, heterotrophic cultivated microalgae. So our final result was not bright green, which is a really difficult colour to commercialize.”  

Future Uses For Algae

Foubert sees possibilities in foods containing algae in their entirety.  “It could be more interesting to process the entire biomass, like some kind of vegetable - I see more potential in that. Flavour and odour do remain a challenge though. But smart marketing can get us a long way.” 

The author originally wrote this piece for Belgian outlet Eos Tracé. Read the piece in Dutch here.

Would you consider eating algae in any of the ways mentioned above? Let us know in the comments below!