Seaweed as a vehicle for nutrients in a circular food chain - innovative steps to accomplish a protein shift (CirkAlg)

In CirkAlg,we will explore the potential of Swedish seaweed as a contributor to the “protein shift”by developing a two-step circular strategy by which the protein content of seaweedproducts can be further raised.

Partner organizations

  • National food agency, Sweden (Public, Sweden)
  • Oatly AB (Private, Sweden)
  • Gastroba Utvecklings AB/VegMe (Private, Sweden)
  • Bua Shellfish AB (Private, Sweden)
  • Kristianstad University (Academic, Sweden)
  • University of Gothenburg (Academic, Sweden)
  • Nordic SeaFarm AB (Private, Sweden)
  • Pelagic Sweden AB (Private, Sweden)
Start date 01/12/2018
End date 31/03/2023
​The project is a collaboration between several Universities, companies and a government agency with the aim to develop techniques to increase the protein amount in seaweed in two steps and in ingredients made from these. In a first step the seaweed is cultivated in nutrient rich media and in a second step scalable processes will be developed to concentrate the protein from the cultivated seaweed. Other central objectives of the project include analysis of tastiness, nutrition value and food safety of the developed protein ingredients and in products containing these.

​The demand for vegetable protein sources is increasing to provide a more sustainable food supply chain and to meet the desired decrease in meat consumption. In CirkAlg, we will explore the potential of Swedish seaweed as a contributor to the “protein shift” by developing a two-step circular strategy by which the protein content of seaweed products can be further raised.

In the project CirkAlg we will explore the potential of Swedish seaweed as a contribution to the protein shift. Seaweed contain varying amounts of protein; about 10-45% of the dried weight, and this protein is very rich in essential amino acids, which are the building blocks of protein. Seaweed is also rich in non-flavoring substances, minerals and vitamins. Some algae also have the well-known marine omega-3 fatty acids that can prevent cardiovascular disease and positively affect brain development.
Aim and objectives
The aims of CIrkAlg are:
  • Develop a new “secondary circular food chain”, with new processes and growth media for tank cultivated seaweed.
  • Use and develop scalable techniques to concentrate seaweed protein to create tasty, safe protein ingredients with high nutrition value.
The amount of protein in seaweed, and in ingredients made from seaweed, shall increase, e.g. by utilizing and further develop a certain technique where protein can be separated from other algae biomass. Through that strategy you can achieve a higher protein amount. The sensory properties of the final product will be evaluated, as well as food safety aspects.

Out vision is that CirklAlg will contribute to a new circular blue industry in Sweden, where algae farmers and food companies work in symbiosis to create favourable conditions for production of a new Swedish vegetarian food source. Taste- and nutrition profile will be optimized in order for the product to be attractive for the ongoing protein shift. In the end we create a more sustainable food production, both financially and ecologically.
How do we work to fulfil our aims and objectives?
​In a first step we cultivate seaweed in chosen growth media in tanks on land. Then, in contrast to cultivating in the sea, you are not dependent on season and can harvest anytime during the year. We work with the two green algae species sea lettuce (Ulva lactuca) and gutweed (Ulva intestinalis), as well as sugar kelp (Saccharina latissimi) that is a brown algae. Aside from the protein amount we also analyse amino acids and other nutrients.

In a second step we use a process where protein from one resource can be concentrated by dissolving them in at a high pH, remove non-protein matter, e.g. carbohydrates, and finally precipitate the protein to solid particles at a pH where the protein has minimal solubility. We recently observed that this technique could concentrate seaweed proteins 4-5 times, reaching isolates with up to 70% protein. However, this process has not yet been optimized for seaweed as a resource and is therefore not sufficiently efficient; we will therefore investigate different strategies to increase the so called “protein exchange”.

To ensure tasty and safe ingredients, sensory analysis and partitioning of potential heavy metals as well as iodine will be recorded during the protein concentrating process, followed by speciation and bioavailability studies. Altogether, CirkAlg will thus take a holistic system approach to fill the protein gap; with the creation of a new secondary food chain based on outlets from the primary chain; altogether contributing to circular food production.

Seaweed has many beneficial properties, but they can assimilate heavy metals when present in the surrounding water. Brown algae can also sometimes become so rich in iodine that the concentration becomes too high. To ensure the complete food safety of our products, we will investigate the presence of heavy metals and iodine in both seaweed and algae ingredients. To be even more on the safe side we will also utilize an in vitro model to investigate how human gut cells takes up heavy metals and iodine from seaweed. This is relatively unknown at present.
​Göteborgs Universitet (GU)
Henrik Pavia
Henrik Pavia

Göran Nylund
 Göran Nylund

Kristoffer Stedt
Kristoffer Stedt

Sophie Steinhagen
Kristoffer Stedt

Högskolan i Kristianstad
Karin Wendin
Karin Wendin

Barbro Kollander
Barbro Kollander

Oatly AB
Karin Peterson
Karin Peterson

Nordic Seafarm AB
Elisabet Brock
Elisabeth Brock

Gastroba Utvecklings AB/VegMe
Lasse Schönemyr
Lasse Schönemyr

Bua Shellfish AB
Magnus Nilsson
Magnus Nilsson

Scandic Pelagic AB
Martin Kuhlin
Martin Kuhlin

Funded by

  • Formas (Public, Sweden)
  • The CirkAlg project and related research in the group of Prof. Ingrid Undeland at Chalmers regarding algae as a sustainable food source was highlighted in a newspaper article in Göteborgsposten 2020-05-16. (in Swedish)
  • PhD student João Trigo from the division of Food and Nutrition Science at Chalmers gave an oral presentation 2020-08-25 at the Seaweed4Health conference entitled “Effect of pH-shift processing on in vitro digestibility and Caco-2 cell bioavailability of Ulva fenestrata proteins”.
  • Kristoffer Stedt and João Trigo made a video to explain which challenges need to be overcome to turn seaweed into the next food protein source.
  • The international Environment section of Deutsche Welle has presented the CirkAlg research in a radio feature ("Living Planet: Seaweed coming to your plate")  where researchers from Chalmers and Gothenburg are talking about seaweed cultivation and seaweeds as a future food source.
  • Two MSc students investigated how Swedish consumers perceive seaweed and how it can be incorporated in our diet (link to article)
  • ScienceDaily, Springwise and Food Supply featured the press release from the CirkAlg publication about the possibility to use process waters from the food industry as cultivation media to increase seaweed growth and protein content. 
  • Ingrid Undeland and João Trigo explained to The Guardian why it is challenging to extract protein from seaweed and possible food applications of this novel protein.
  • SVT, in their news segment Rapport, featured the press release from the CirkAlg publication about the possibility to use process waters from the food industry as cultivation media to increase seaweed growth and protein content.

Page manager Published: Fri 04 Nov 2022.