Algae, promising new ingredient

Published: 14-10-2014

Pasta, toast, pie and pudding: a growing number of food products contain algae-based ingredients. Algae production and biorefinery are becoming more efficient and food industry experts predict rapid growth of applications over the next few years. For some uses of algae, laws and regulations are still being developed.

Small is beautiful. That is definitely true when it comes to microalgae, single-celled organisms that live in both fresh water and oceans. Microalgae produce oxygen and are crucial for life on earth. They can also be a source of proteins, carbohydrates, lipids, polyunsaturated fatty acids, pigments and antioxidants.

Microalgae are often referred to simply as algae. Macroalgae, on the other hand, are better known as seaweed. Algae come in many different qualities. Those which are intended for food applications have to meet strict requirements and must not be contaminated with any moulds or bacteria. European regulations are currently being devised.

Food companies large and small see potential in using algae. “Algae are a natural, sustainable resource,” said Peter Haring, R&D manager at Unilever. “They use photo-synthesis to turn carbon dioxide into usable materials. They don’t need much else. And they can grow in places where you can’t grow any food crops. As such, algae could
fit in well with Unilever’s sustainability goals. We think algae will become increasingly important as a food ingredient. But consumer acceptance of such new ingredients is a bit of a concern. Consumers have to take to it. Right now it’s a bit like ‘we fear what we don’t know’.”

Reinier Smit of algae producer Nutress does not believe consumer acceptance is the biggest hurdle for algae in the food industry. “Chlorella has been used as a food ingredient and supplement for ages. And modern consumers are accustomed to new ingredients. Algae-based bread, toast and crackers are widely accepted. And many athletes are familiar with the benefits of our product when used in pastas. And don’t forget about
facial masks. Many of those are algae-based. Acceptance has never been a problem.”

Smit says European legislation on algae is the bottleneck. “Europe hasn’t got its organic certification sorted yet. Asia has. As a result, ever larger amounts of algae products from Asia are entering the European market. We’ve brought this up with the Dutch Ministry of Economic Affairs and SKAL, the Dutch organic certification body. The Netherlands has a lot of expertise in algae cultivation. We should be able to capitalize on that head start.”

Several parties are developing expertise in algae cultivation systems, optimizing biorefinery and safe applications. In 2010, Wageningen University opened AlgaePARC. Four years later, their algae cultivation experiments are meeting expectations, according to René Wijffels, Professor of Bioprocess Engineering in Wageningen and AlgaePARC’s managing director. “Right now, average production costs at pilot scale are down to €2 per kilogram of dry matter, ” Wijffels said. “We expect this to drop to less than €1 per kilo in the next 5-10 years. At that point, algae will become highly profitable for the food industry.”

AlgaePARC was used to comparing different production systems, Wijffels explained. “For bulk production, we’re thinking of closed systems in southern Europe. Conditions are good there and there’s enough light for the algae to grow. The cost of producing a kilo of dried algae using a flat plate photobioreactor is €2.25 in The Netherlands, but only €1.37 in the Canary Islands.

Using a more sophisticated system in Mediterranean countries, we expect the cost to drop to €0.75 per kilo. For cultivating specialties, like algae used as a pigment or ingredient in nutraceuticals or pharmaceuticals, greenhouse cultivation might be the best option.”

It is not just algae cultivation that needs optimizing. The same is needed for biorefinery. The cost of separating and purifying biomass is estimated to be €1.50 per kilo. “This could stand some serious improvement over the next few years. Cultivation and refining costs are offset by the sales revenue of the separate substances. I expect to achieve the break-even point in about 5-10 years. That’s when algae will become a serious alternative source of lipids, proteins and carbohydrates,” Wijffels said.

Meanwhile laws are being written to regulate application of algae. “European and national legislation for food products and ingredients based on algae differs according to the type of product,” said Karin Verzijden, lawyer at Axon Lawyers. “The specific type of algae and the type of product it is used in determine which regulations are applicable. For instance, if we’re talking about a food supplement, different regulations apply than if we’re talking about an additive. In some cases, the product is classified as a novel food. That’s the case if it wasn’t part of our regular diet in the EU before 1997. But in order to trade algae as a novel food in the EU, you need prior approval. This is a very lengthy process and the applicable regulations aren’t even in place yet. The aim is to shorten the approval process.”

Practical applications
Algae come in many shapes and sizes. There are about 45,000 varieties that are known to have properties useful to us. The variety and the cultivation conditions determine the algae’s composition. Depending on their composition, algae can contain 50-70% oil, up to 60% protein or up to 60% carbohydrates. Their taste ranges from sweet to fishy. There seems to be an algae for every conceivable application.

Many food applications are made with fats in the shape of triglycerides (TAG). These fatty acids are precisely how algae store fat under stress. Therefore algae can be a source of vegetable oil that can be used in all sorts of products ranging from cooking oil to margarines. Algae-based oil can replace rape-seed, palm, soy and sunflower oil in food products.

The nutritional value of amino acids from various algae is high. According to the WHO/FAO it is comparable to that of proteins from egg, soy and wheat. In the long run, algae-based products could become a sustainable alternative to meat, milk or eggs.

Algae can also store large amounts of carbohydrates in starch grains and in their cell walls. It is not only possible to extract common types of sugar like arabinose, xylose, mannose, galactose and glucose from algae, but also less common types such as rhamnose. Because carbohydrates are in great demand as a commodity this drives up the price. Algae are thought to have great long-term potential as an alternative carbohydrate source.

Valuable components
Algae can also be a source of other valuable components such as vitamins, pigments and antioxidants. Cultivation of algae for these purposes will occur on a smaller scale than algae production for lipids, proteins and carbohydrates.