Torula yeast meal in feed for Atlantic salmon, effects on growth and gut microbiota

The scientific article "Torula yeast in the diet of Atlantic salmon Salmo salar and the impact on growth performance and gut microbiome." was recently published by the scientific journal Scientific Reports, which is published by Nature. The effects of Torula yeast meal on the growth performance and gut microbiome of farmed salmon were investigated, where conventional proteins in feed were replaced by yeast meal. The results may surprise you.

With the rapid growth of salmon farming, the need to find and develop suitable substitutes for traditional protein sources in feed increases. Torula yeast flour (Candida utilis) has been defined as a neoprotein (e. Alternative Protein) which can replace traditional protein in feed. The yeast can be grown sustainably. This study examined the effects of yeast meal on growth performance and gut microbiota in freshwater Atlantic salmon. Feed containing protein from seafood, eg fishmeal, as well as mixed marine and plant protein where conventional proteins were replaced by increased amounts of yeast meal (0%, 10%, 20%) were tested.

This study showed that during the growth stage of freshwater salmon, yeast meal can partially replace traditional proteins in compound feed, but that the optimal amount of intake depends on the total composition of the feed and the types of proteins being replaced. In the feed containing seafood protein, this study revealed that 20% yeast meal can be added to the feed without altering growth performance and with potential benefits to the gut microbiota such as an increase in some lactic acid bacteria.

In comparison, in the feed combining seafood protein and plant protein, 10% yeast meal content supports better growth performance than conventional proteins. At the higher intake level, 20%, there was no growth benefit and potentially adverse changes in gut microbiota, such as a decrease in lactic acid bacteria and an increase in bacterial abundance associated with slower growth in other salmonids.

Find out more about these interesting results and read the full scientific article here

Birgir Örn Smárason professional manager at Matís and Sigurlaug Skírnisdóttir project manager at Matís, are among the authors of the article, for more information you can contact them at the following email addresses and


The green entrepreneurs of the future


Katrín Hulda Gunnarsdóttir


Green entrepreneurs of the future (GFF) is an educational project at Matís that started in June 2021. The mission of the project is to educate Icelandic elementary school students about climate and environmental issues, and the project is funded by the Climate Fund. Katrín Hulda Gunnarsdóttir, an expert at Matís has worked on the project together with Justine Vanhalst, project manager at Matís. Katrín shares with us the journey of the project from the beginning.

"It was pleasing to see how interested and really knowledgeable the kids were about the effects of climate change. It soon became clear that this is an issue that is on their minds and they are very aware of the discussion that is taking place in society at the moment."

Why Green entrepreneurs of the future?

"I had just finished a teacher training course where I had learned various concepts such as problem-solving learning, student-centered learning and gamification. When I saw a job advertised to work at GFF, I thought it was a perfect fit. It both fit well with the philosophy I wanted to adopt as a teacher, addressed issues that I consider important and would give me experience in creating learning materials. I applied for it and have been here ever since," says Katrín Hulda.

You don't have to look far beyond a dose to have an effect

"The goal of GFF is to arouse the interest and increase the knowledge of primary school children about climate and environmental issues, innovation and sustainable resource use in order to mobilize them in the fight against climate change and encourage them to green innovation."

"This was done by providing innovative and interesting education and engaging them in conceptual work and innovation in cooperation with companies in the local area with a special focus on environmental impact and resource use. With that, the intention was to strengthen relationships between parties within the students' home areas and show them that often you don't have to look far to be able to make an impact." 

"With innovative education, we were mainly thinking about making it exciting, impressive and empowering for the kids." It has the effect of reducing climate anxiety. In order to combat climate anxiety among children and young people, it has been recommended, among other things, to tell them the truth, give space to difficult feelings and allow them to take part in the fight. The authors of the GFF curriculum had this in mind when writing. Katrín Hulda explains.

Challenges following Covid 19 were solved with resourcefulness

"The goals were achieved and the project went better than we dared to hope. Of course, the organization changed a little due to the Covid-19 outbreak, but the schools were incredibly resourceful in sorting things out. As an example, in Sauðárkrók it was not possible to visit the companies due to a ban on visitors, due to the Covid mass restrictions. Instead, the students received visits from the companies, where they were told about their activities. There were presentations, videos and many other things, and it seemed like a great success."

Year school

"Feedback from teachers and other participants came out very well, and was very valuable in refining the project for the next round." It can also be mentioned that there is a great lack of study materials on climate and environmental issues for this age group, and therefore there is a certain gap that the project fills in," says Katrín Hulda.

Did something new or even unexpected come to light?

"It was fun to see how good the kids are at innovation. Not only do they come up with brilliant ideas, but they also showed good work practices and achieved a lot in a very short time when the MAKEathons took place. MAKEathon is an innovation competition where you compete to come up with the best solution to a given problem. In our case, the competitions took place over two days and the kids made prototypes, models or posters of their solutions to environmental problems.

It was pleasing to see how interested and really knowledgeable the kids were about the effects of climate change. It soon became clear that this is an issue they are passionate about and they are very aware of the debate that is taking place in society at the moment. Moreover, there was a great will to fight among them, but they feel that this is the biggest problem facing the rest of the world," says Katrín Hulda.

"It was possible to localize the projects according to the needs of each individual school. The teachers took the projects and made them their own, for example, teachers at Grunnskóli Bolungarvík linked the subject matter to the history of Bolungarvík, and teachers at Sauðárkrók took advantage of the opportunity and used the one experiment to teach their students how to report.

"It was also cool to see how empowering the MAKEathon was for the students. Having the opportunity to deal with "real problems", ie. the same problems that the adults in their immediate environment face, seemed to give them new assumptions and ambitions. It was very important to them that this was not just some textbook example that was then put in a drawer and never done anything more with."

The first year of the project ended with a bang and the impact is not hidden

"The first year of the project, hopefully of many, ended this spring with a bang. The national MAKEathons competition, GFF's innovation competition, was held and the results were presented during Innovation Week. All participants were very satisfied and there seemed to be a great desire to continue the project.

The impact has primarily been on the students. They have learned a lot, both academically, ie about climate change and its effects, but also practically, i.e. work practices An increased understanding of the nature of climate change and its effects, among other things, on their local environment has been achieved. The kids' perspective on their hometown changed as a result, as well as on the companies that operate there. They learned to see opportunities in their local environment. FabLab smidjarnar and Djúpið Frumkvöðsetur came in strong, but their expertise includes teaching kids innovation and entrepreneurship.

The teachers have also received new weapons in their pedagogical arsenal, both in terms of theoretical knowledge and also new teaching methods. Hopefully, these methods will continue to be useful to them, whether they teach environmental science or some other subject. We must not forget the impact the project has had on us. We are full of inspiration and would like to take the students, and their creativity, as our example," says Katrín Hulda.

Year school
Bolungarvík elementary school

What are the next steps?

"The course material itself will be made available online as agreed. It would be nice to be able to publish it properly though, with illustrations and a nice presentation. The intention is to apply for a grant for such a thing."

"As for the next school year, the registration of schools that want to participate has been opened. Both the oldest classes of primary schools and secondary schools can participate. Matís' role is to be within their reach, but the study material is all there, so it shouldn't take much intervention for the MAKEathons to come. Registration has been opened and will end on September 1. Those interested receive a short Google survey that they fill out."

Those who wish to learn more about the project or access teaching materials are directed to the project's website: The project also maintains an Instagram page with various information and pictures:

Special thanks to our partners: Stefán Þór Eysteinsson at Matís, Gunnar Þórðarson at Matís, Ragnhildur Friðriksdóttir former employee of Matís, Year School Sauðárkróki, Nesskóli Neskaupstaður, Elementary School Bolungarvík, Djúpið Frumkvöðsetur Bolungarvík (Gunnar Ólafsson), FabLab Ísafjörður, FabLab Neskaupstaður, FabLab Sauðárkrókur, N4 Television, Cambridge University. Dögun shrimp processing, FISK Seafood, ArcticFish and Eskja.

Registration has started

Registration for Green Entrepreneurs of the Future for the next school year has opened. The project is suitable for the oldest grades of primary school and the basic courses of secondary school. For more information, those interested can contact the project manager, Justine Vanhalst at Registration is done by clicking the button below:


Research on horsemeat

Horsemeat is a limited resource and a high quality product. Are there opportunities in product development and marketing that are not being exploited?

In this episode we hear from Eva Margrét Jónudóttir who is a specialist at Matís, but she has done various research on horsemeat. Among other things, Eva has researched the attitudes and buying behavior of Icelandic consumers and researched meat quality in foal meat. Eva talks pleasantly about the results of that research and it is extremely interesting to hear her report on the results of the quality and shelf life of horsemeat.

Listen to the full episode below:

The host is Ísey Dísa Hávarsdóttir


Stress of salmonids during pumping

Stress of salmonids in farming can be important for their welfare, growth and development, and can also affect the quality and shelf life of products. The main cause of salmon death in aquaculture is treatment against salmon lice, which can reduce the resistance of fish to infections and cold, as well as reduce growth. Salmon lice cost Nordic salmon farming around ISK 140 billion a year and are therefore a huge problem for the industry.

The main reason for the negative effect of treatment against lice is poor treatment of pumping salmon. Vacuum pumps are most commonly used, which cause stress and some shock to the fish; but during the pumping, an air space is evacuated which pulls the fish up into a tank, which is then fired into compressed air to push it to the place it is intended to go to. This is done both during lice treatment and when fish are pumped for slaughter. It can take a long time for fish to recover after treatment and start taking food again, and pre-slaughter shocks can cause stress that reduces product quality.

In light of this, pump equipment manufacturers have been looking for new ways of pumping salmonids and the Icelandic company Skaginn 3X has been developing a so-called spiral pump (Archimedes pump) as a solution to this problem. The pump has been named ValuePump. In the autumn of 2020, Matvælasjóður provided the company Skaginn 3X, together with partners, with funding to develop, build and test a prototype of ValuePump. The prototype was ready for testing in early 2022, when comparative measurements were made of ValuePump's performance and a conventional vacuum pump, which is currently used for pumping live salmon for slaughter and for handling in and around pens. The comparative measurements used DST except from Stjörna-Oddi, which recorded temperature and heart rate in fish, in addition to which the stress hormone Cortisol was measured in the blood. The comparative experiments took place in the facilities of the Marine Research Institute in Reykjanes under the direction of the institute's experts, Stjörna-Oddi and Matís.

Prototype ValuePump next to the vacuum pump used in the comparative studies
Employees of the Marine Research Institute during the pumping experiments

The results of comparative experiments showed a significant difference between groups following pumping. Heart rate rose sharply during pumping, but the ValuePump group was quicker to recover and regain baseline. Pumping with a vacuum pump had a much greater long-term stress effect than experimenting with maximum stimuli where the fish crackled dry. There was also a large visual difference between the groups according to the type of pump, as fish pumped with a vacuum pump often came injured or even dead from the pump, swam sideways or upside down hours after pumping. Fish that were pumped with ValuePump, however, did not experience any visible damage during the pumping and seemed to be doing well after it.

The results of the comparative experiments must be considered very positive, as they indicate that ValuePump can significantly reduce the stress of salmonids during handling. This Icelandic innovation could therefore have a lasting effect on the welfare and profitability of salmon farming.

The participants of the project would like to thank the Food Fund for supporting the project.

The full report is available here

Further information is provided by Gunnar Þórðarson


Ensure virus-free Icelandic potato seed


Sæmundur Sveinsson

Group Leader

In December 2021, Matís and the Farmers' Association of Iceland reached an agreement on tissue culture of potato seed and work on the project has begun at Matís. The last issue of Bændablaðið publishes a discussion of the project, which discusses the agreement and the main aspects of the project.

The purpose of tissue cultivation of potatoes is to ensure that Icelandic farmers continue to have access to healthy seeds of the four Icelandic varieties: Premier, Gullauga, Rauðar íslenskum and Helga. The purpose of stock breeding is to promote the production of stock seeds that are free of viral diseases. Viruses are easily transmitted between mother potatoes and offspring, so tissue culture is the only way to maintain virus-free seeds. Viruses are very harmful to farmers, but virus-infected seeds produce up to a third less crops. Sigurgeir Ólafsson, a former specialist at RALA, created virus-free strains of the Icelandic varieties. The goal of this project is to maintain these stocks. In a collaborative project between the Farmers' Association and Matís, Matís will be responsible for the implementation of work components related to the tissue culture itself.

Bændablaðið quotes Axel Snæland, chairman of the horticultural farmers 'department within the Icelandic Farmers' Association:

"The horticultural farmers 'department within the Farmers' Association was responsible for concluding the agreement with Matís, which includes the tissue cultivation part of the stock cultivation of seed potatoes. Matís' project involves producing tissue-grown seed potatoes, Premier, Gullauga, Helga and Rauðir íslenskum, which are free of viruses and diseases, such as itching and rot. In addition, the potatoes are selected in terms of appearance. '

The project is progressing well and at the moment, potato plants, grown from sprouts, are in glass bottles under special controlled conditions in a tissue culture chamber in Matís' premises, as can be seen in the attached photos.

After further research, it will be possible to return small plants in a cultivation run for further cultivation to seed potato growers for greenhouse cultivation in soil next spring, if all goes well.

The article can be read in its entirety in Bændablaðið here: Stock cultivation of seed potatoes


Work of a specialist in the field of chemical measurements (Neskaupstaður)

Matís has a vacancy for a specialist. We are looking for an independent and ambitious individual to work in a strong team.

Main tasks and responsibilities:

  • Chemical measurements and maintenance of equipment
  • Maintenance of measurement methods and projects in an accredited environment for industry and research projects
  • Dissemination of information and communication with customers
  • Purchasing and communication with suppliers

Educational and qualification requirements

  • BSc degree in Chemistry, Chemical Engineering, Biochemistry or equivalent
  • Good co-operation skills and flexibility in communication
  • It is desirable that the person in question has worked with chemical measurements and has experience in the maintenance of equipment.
  • Initiative, reliability and ambition

The employment rate is 100% and the job is located in Neskaupstaður

With reference to Matís' gender equality policy, all genders are encouraged to apply. Applications must be accompanied by a detailed CV and cover letter outlining the applicant's qualifications for the job in question. You must also include the name and telephone number or e-mail address of two referrers who can confirm the applicant's qualifications.

The application deadline is 07.07.22

Further information about the job can be obtained from Natasa Desnica,


Bolungarvík Primary School won by a landslide in the national competition of the Green Entrepreneurs of the Future 2022


Justine Vanhalst

Project Manager

At the end of May, the MAKEathons National Competition, the Innovation Competition of the Green Entrepreneurs of the Future, took place. There, the three schools, Nesskóli, Grunnskóli Bolungarvíkur and Árskóli, competed for the finals.

Each school submitted a video in which they explained their solutions to the environmental challenges in their home area. The competition was stabbing, but in the end it was Grunnskóli Bolungarvíkur that won by a landslide. Among them were Hildur Ágústsdóttir, a teacher, and Gunnar Ólafsson from the Deep Entrepreneurship Center.

Bolungarvík Primary School grappled with the challenge:

"How to make better use of aquaculture waste"

and the solution that worked was entitled: "Utilizing waste from aquaculture in a sustainable way"

Below you can read the feedback that the winning team received from the jury:

"You are resourceful and solution-oriented. You spotted environmental problems caused by aquaculture in the sea and looked for solutions. It was great to see the shit that has accumulated, but the public usually does not get that perspective. Your task is to turn waste and sediment into a resource that can be used, and could therefore benefit both nature and fisheries companies. We encourage you to continue working on the solution and keep in mind the importance of biodiversity in marine ecosystems, but fire in the sea can harm it if left unchecked. "

The jury consisted of:

  • Lenya Rún Taha Karim Deputy Member of Parliament for Pírata and law student
  • Margrét Hugadóttir webmaster and project manager at Landvernd
  • Þóra Valsdóttir project manager at Matís

For more information, please contact the project manager of the Green Entrepreneurs of the Future: Schools wishing to participate are especially encouraged to contact (reporters can be contacted by phone: 762 0266).

Here you can follow the progress of the project:

Peer-reviewed articles

Interactive governance of whale ecosystem services: governability assessment of three case studies in the Arctic

The social-ecological change in the Arctic is accelerated by the multifaceted effects of climate change and globalization. Among other things, this means changing human-ecosystem dynamics through altered availability, co-production, and governance of ecosystem services (ES). A group of species illustrative of this change are whales, migratory species that have played an important part in the culture and subsistence of Arctic communities for millennia. This study explores the changing human-nature interactions and whale ES governance by combining ES and interactive governance theories. A multi-method approach is applied to assess qualitatively the qualitative governability of whale ES in three Arctic coastal locations: Húsavík in Iceland, Andenes in Norway, and Disko Bay in Greenland. Based on a literature review, stakeholder mapping, observations, and analysis of 54 semi-structured stakeholder interviews, the study finds that whale ES governance involves multiple actors with differing preferences and values and that much of it happens outside of formal institutions, necessitating inclusive approaches to improve it. The study reveals some whale ES governance deficiencies and potentials, such as a mismatch between governance scales and a need for more formal governance practices based on scientific research and stakeholder inputs. Governance frameworks were present for provisioning whale ES related to whaling, but they were lacking for non-consumptive whale ES, such as whale watching. Addressing these issues can help to direct marine resource management toward sustainability by making it more inclusive, adaptive, and reflective of stakeholder needs and values. This goal could be advanced by applying the governance principles that view humans as an integral part of social-ecological systems, eg, ecosystem stewardship and ecosystem-based management.

Link to article

Peer-reviewed articles

Socio-cultural valuation of whale ecosystem services in Skjálfandi Bay, Iceland

The study examines the socio-cultural values of multiple ecosystem services (ES) sourced from whales in Skjálfandi Bay, North Iceland, with many beneficiaries living in and visiting the town of Húsavík. The study begins to address the research gap in non-monetary valuation of marine ecosystem services. Based on a multi-method approach, it elicits stakeholders' perceptions of the contribution of whale ES to human wellbeing using stakeholder mapping, semi-structured interviews, observations, and socio-cultural preference surveys. The key whale ES identified by the local stakeholders were cultural, most frequently mentioned being recreation and education. The most commonly mentioned ES values were related to economic benefits from the whale watching industry. The preference survey reveals that regulating and maintenance ES were valued most highly with a mean score of 4.0 out of 5.0, cultural ES were second with a mean score of 3.5, and provisioning ES in the form of food and raw materials were valued the least with a mean of 0.75. Interview data also reveals some marine ES management challenges originating from intensified tourism, industrial development, and climate change. The results of the study have the potential to inform marine resource management in Iceland by including socio-cultural values associated with whale resources.

Link to article

Peer-reviewed articles

Whale Ecosystem Services and Co-production Processes Underpinning Human Wellbeing in the Arctic: Case Studies from Greenland, Iceland and Norway

The concept of ecosystem services (ES) has only just begun to be applied in the Arctic, and to an even lesser extent to marine mammals, such as whales. This chapter develops an ES cascade model and related ES co-production processes as they apply to whale resources in the Arctic. The result is a new conceptual model demonstrating the interconnectedness of social-ecological processes involving natural and human capital that enhance human wellbeing through the co-creation of whale ES. An ES cascade model is presented for whale ES, which connects the five linked stages of such ES production: the biophysical structure, functions, ecosystem services, the benefits to human wellbeing, and associated values. They are further expanded to include the co-production processes of whale ES as well as its main stages, inputs, and flows. These processes are illustrated using examples from ARCPATH case studies of coastal communities dependent on whale resources: Húsavík in Iceland, Andenes in Norway, and Ilulissat / Disko Bay in Greenland. The chapter aims to improve the understanding of the human dimensions of ES and the underlying processes that enable Arctic coastal communities to benefit from whales. It provides a starting point for further analysis of possible research and management approaches regarding whale resources in the Arctic.

Link to article