Microalgae | Health & Environmental Benefits

While seaweed is becoming more renowned as the food of the future, its microscopic relatives, the microalgae, are looking far more promising. If the mention of algae makes you think of green ooze in ponds and swimming pools in the summer, then you’d better suppress your disgust. Because that ooze just end up on your plate.

By 2050, there will be 9.3 billion people: 1.5 billion more than today. Those extra mouths will have to be fed, preferably in ways that spare our environment as much as possible. While about half of our proteins are supplied by animal products today, the United Nations estimates that in 30 years, the meat industry will only be able to meet approximately 27% of the demand for protein. Algae represent an alternative to traditional protein sources since more than half of their dry matter consists of proteins.

What are algae?

Microalgae or ‘phytoplankton’ live in fresh and saltwater, where they make up the base of the food chain. They consist of separate cells, sometimes occurring in little groups or chains. Other microalgae cannot be seen with the naked eye; the green, brown, blue or red mass is only visible during an algae bloom. In total, there are approximately between 200,000 and 800,000 varieties of algae. With such variety, algae guarantees a range of properties and possibilities for different applications, even in the food industry.

Health benefits of algae

The Spirulina algae can contain up to 63% protein. For comparison, soy (an important plant-based protein source) only contains 40% protein.

Besides being little protein bombs, algae are also sustainable sources of long-chain Omega-3 fatty acids. Nowadays, we get these fatty acids mainly from fish or fish oil - which seems roundabout, considering fish also get their Omega-3 from algae. But with overfishing and the increase of vegetarian diets worldwide, algae can be an attractive alternative.

Environmental benefits of algae

Algae grow very rapidly, while also being relatively undemanding on resources. “They can be intensely cultivated in attics, basements, closed factory halls, on boats on the sea… you name it. Algae wouldn’t take up any natural land or other types of valuable farmland”, says Siegfried Vlaeminck, a researcher at the University of Antwerp, whose team develops sustainable microbial technologies. 

“Life-cycle assessments show that growing algae is a lot more sustainable than growing plants. Compared to other sources of protein they also require far fewer fertilizers or chemicals for crop protection. Plus they emit a lot less greenhouse gases.”

Algae minimise nutrient loss

Because of algae’s efficient nature, their cultivation requires fewer fertilizers. Not only do they make careful use of precious resources like water and land, but they are also a lot better than other protein sources at turning nutrients from fertilizers into food. 

For example, the protein building blocks in meat originally come from fodder, which is made of plants that frequently get their nutrients from artificial fertilizers. Many of the nutrients that farmers initially add to fodder crops get lost along the way - such as from nutrient runoff during heavy rainfall or because nutrients are released through cattle's manure. So, a slice of meat is estimated to have a mere 14% of the nutrients originally added by farmers.  In vegetables, approximately half of the original nutrients get lost. Then, more nutrients are lost during the processing, distribution and preparation of food. But with microalgae, nutrients are retained at a much higher rate. 

Their low resource requirements and high efficiency make algae very interesting for space travel. The European Space Agency develops ecosystems that can provide food for astronauts in space. The project is called MELiSSA, an acronym for Micro-Ecological Life Support Alternative. In MELiSSA, Spirulina algae provide food and oxygen to the ecosystem, even proving to be highly resistant to cosmic radiation. 

Algae are expensive 

In theory, it should be possible to develop sustainable algae production. But, those who dream of a sustainable world filled with algae smoothies and green sandwiches are quickly brought back to reality by its price point.

“Algae are an expensive niche product”, clarifies Imogen Foubert, head of the Food & Lipids lab at the KU Leuven, who has done a lot of research into fats in microalgae.“Current production only happens on a very small scale. As we start cultivating more, algae will become more affordable. But I still suspect they will remain on the expensive side. The industry and the scientific world are slowly realising that algae will more likely be used in small portions, having great effects - like replacing fish oil as a source of long-chain Omega-3 fatty acids in margarine or supplements. These first applications could boost algae production, which would help decrease the product price. Only then can we move towards bulk proteins or fats.” 

While you could also replace fats like palm oil with fats from the right type of algae, price is still an issue. Palm oil is a commonly used bulk product that’s very cheap, so even if algae is a more sustainable alternative, it still has many profitability challenges before it can replace palm oil. 

Vlaeminck puts the cost of algae into perspective, “When you express the price in terms of euro per kilogram of protein, it’s not too bad - Quorn products are sold at the same price. But, they are still twice as expensive as meat.” However, one solution to make products cheaper is to mix algae with other proteins. 

The best places to grow algae

The first steps toward broader use of algae have already been made, with algae growing in warmer places. “In our regions, large-scale productions would probably be too expensive. We should rather consider southern countries with more sunlight and where production would be stable all year. Today, Spirulina mainly comes from the South, for example, China”, Vlaeminck says. 

“As a source of protein, microalgae aren’t a business case yet in Flanders or the Netherlands. But there are large-scale projects in Spain, Portugal and Israel. They often focus on algae components with a high added value, like astaxanthin, a red pigment used for salmon farming and other fish farming,” confirms Marie Demarcke, Innovation Manager at Flanders’ Food.

EU regulation around algae

For now, the production of algae and other microbial products is hampered by the European legislation on “novel food”. According to EU regulation, foods not sold within the EU before 15 May 1997 are considered “new” and would need clear evidence that they are safe and pose no health risks. As all microalgae – except for Spirulina and chlorella – are classified as “new”, they would have to go through lengthy procedures to prove they meet safety standards. 

So, is the idea of having microalgae on our plates more than a distant dream or an expensive splurge? One thing’s for sure: we won’t be eating our own microalgae steaks soon. But algae still has great potential as a more sustainable protein alternative. So it’s still interesting to explore different productivity-boosting ideas or perhaps new uses in the food industry. 
 

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