Peer-reviewed articles

Genetic mixing of wild Icelandic salmon (Salmo salar) and farmed salmon of Norwegian origin

Genetic mixing with farmed salmon can change the genetic composition of wild populations, lead to changes in life history parameters and even cause population decline. In Iceland, aquaculture of salmon of Norwegian origin is a growing industry. The production of farmed salmon has gone from almost nothing in 2010 to 43,000 tons in 2022. According to the current advice of the Norwegian Marine Research Institute (risk assessment of genetic mixing), it is estimated that it is possible to raise 106,500 tons of fertile salmon without causing a negative impact on useful wild populations. salmon

In a genetic study from 2017, where 15 microsatellites were used, signs of genetic admixture were found in rivers close to seagull farming in the Westfjords. In this study, salmon samples were taken in rivers around the country and the number of samples was almost ten times higher. A total of 6,348 salmon fry from 89 rivers were studied and emphasis was placed on areas in the vicinity of sea pig farming.

Most samples belonged to the spawning cohorts of 2014-2018, when the production of farmed salmon was around 6,900 tons on average. Samples were genetically analyzed with 60,250 alleles (SNP genetic boundaries) and the genetic information of 250 farmed salmon was used for comparison. The coefficient of genetic difference (FST) between Icelandic salmon and farmed salmon was 0.14 on average (based on 34,700 SNPs) and 0.62 for the genetic boundaries that showed the greatest separation between the two groups (196 SNPs). Genetic admixture was analyzed by multivariate analysis (PCA) and in the models of the programs ADMIXTURE, STRUCTURE and NewHybrids.

A total of 133 first-generation hybrids (offspring of farmed and wild salmon) were detected in 17 rivers (2.1% samples, within 18% rivers). Older admixture (second generation or older) was detected in 141 juveniles in 26 rivers (2.2% samples, within 29% rivers). First-generation hybrids were more common in the Westfjords than in the Eastfjords, which is consistent with the fact that the fire in the Eastfjords started later and has been less extensive.

Hybridization was usually detected less than 50 km away from breeding areas, but some hybrids were found up to 250 km away. On the other hand, older genetic admixture was more frequent in the Eastfjords than in the Westfjords and is most likely related to the fire that operated there at the beginning of this century. Older genetic admixture was most evident in Breiðdalsá and was detected in 32% (72 out of 228) of the juveniles. More research is needed on the intergenerational distribution of hybrids, the extent and causes of the spread of older admixtures.

As mentioned above, the study analyzed the effects from the early years of the current farming, when production volumes were low, and older experiments in sea pig farming. The results in this report show that genetic mixing has occurred at relatively low breeding rates.

Peer-reviewed articles

Novel biomaterials and biotechnological applications derived from North Atlantic sea cucumbers: A systematic review.

In book: The World of Sea Cucumbers, Challenges, Advances, and Innovations. 1st Edition, pp. Editors: Annie Mercier, Jean-Francois Hamel, Andrew Suhrbier, Christopher Pearce. ISBN: 9780323953771.

Reports

Color of supercooled gills

Published:

15/07/2020

Authors:

Gunnar Þórðarson, Margrét Geirsdóttir and Sigurjón Arason

Supported by:

AVS Fisheries Research Fund

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

The color of the gills has long been used to evaluate the freshness of fish, but it is known that during storage the color changes and they darken. When ultra-skinning of salmon was introduced, which improved the quality of production, billfish followed the short-rib method, where the gills darkened during cooling; but the color change can cause difficulties in the market and give the false impression that freshness is not good enough.

It was therefore important to get answers as to why this color change occurs during hypothermia, which is defined as cooling below 0 °C and less than or equal to 20% of the water content of the muscle being frozen. The research question was therefore whether it was the salt or the cold in the refrigerant that caused the color change. The result of the project is unequivocal that the cooling is the causative factor and the color of the gills changes when freezing during cooling which is based on a cooling medium of -2.5 °C and a cooling time of about 80 minutes. 
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The color of the gills has long been used to evaluate the freshness of fish, but it is known that during storage, the color changes and they darken. When super chilling of salmon was introduced which improved the quality of production, a problem followed by the gills darkening during chilling; but the color change can cause difficulties in the market and incorrectly indicate that freshness is not satisfactory.

It was therefore important to obtain answers as to why this discoloration occurs during supercooling, which is defined as cooling below 0 ° C and less or equal to 20% of the water content of the muscle being frozen. The research question was whether it was the salt or the cold in the refrigerant that caused the color change. The result of the project is unequivocally that the cooling is the cause and the color of the gills changes when it freezes during cooling, which is based on a refrigerant of -2.5 ° C and a cooling time of about 80 minutes.

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Reports

Cross-ownership in the Icelandic seafood industry and the potential effects on UK supply: A Matis report for Seafish and the Grimsby Seafood Cluster

Published:

22/11/2023

Authors:

Jónas R. Viðarsson, Gunnar Þórðarson

Supported by:

SEAFISH

Contact

Jónas Rúnar Viðarsson

Head of Value Creation

jonas@matis.is

This report is commissioned by Seafish and the Grimsby seafood cluster in the UK with the aim to get and overall understanding of connections and dependencies in ownership of the largest seafood companies in Iceland, and how these can potentially affect supply to the UK.

Quota consolidation has been a feature of Iceland's fisheries sector since 1991, when the government introduced individual transferable quotas (ITQs) across all species. This allowed some companies to buy up quotas from others, and catch them in a way which, in theory, ought to be more efficient. The concept is that overall economic return from the resource will be maximized by allowing for such optimization. Now, almost three decades later, the economy of scale has resulted in extreme consolidation across the seafood sector, where smaller companies have merged into larger ones or been bought up by the big vertically integrated seafood companies.

The catching and processing sectors have been going through a major development phase in recent years, as vessels and processing technologies have advanced and become much more efficient. This however comes with a price tag that only the larger companies can afford, which in return has escalated consolidation. As an example, in 1991 the ten largest companies owned 24% of the overall quota in cod-equivalent but now have possession of 52% of the quota; and the twenty largest companies own 72%.

In order to maintain diversity in the industry and to avoid ending up with only a handful of companies possessing the entire quota, the government placed a cap (quota ceiling) on how many individual companies are allowed to own the quota. For the main ITQ system this cap is 12% in cod-equivalent and for the coastal fleet (vessels below 15 meters) the quota ceiling is at 5%. However, at present, if a company holds a stake of less than 50% in another firm, that latter firm's quota holdings do not count towards the quota ceiling. As a result, many of the larger companies now have cross-ownership that is not very transparent. Clusters of connected companies have therefore emerged, which are dependent on each other. 

In the spring of 2019, the government formed a committee that was to review and suggest how "connected companies" should be defined with regard to the quota ceiling. The committee returned its suggestions at the end of 2019. The main results were that majority ownership should still be needed to count quotas against the ceiling. Increased transparency is however suggested, obliging companies that possess more than 6% of the quota (2.5% of the coastal fleet quota) to disclose cross-ownership with the Directorate of fisheries. 

This report gives a brief overview of cross-ownership and dependencies between the largest seafood companies in Iceland and concludes how these may affect supply to the UK, particularly in regard to supplies of fresh whole fish. The report also provides information on major investments that have occurred in the last few years that are likely to affect the supply of fresh whole fish to the UK.

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Reports

Supply Chain Network analysis and recommendations for improved logistics within the SUPREME project

Published:

18/09/2023

Authors:

Jónas Baldursson, Jónas R. Viðarsson, Magnus Stoud Myhre & Valur N. Gunnlaugsson

Supported by:

The research council of Norway (project no. 970141669)

Contact

Jónas Rúnar Viðarsson

Head of Value Creation

jonas@matis.is

This report provides an overview of the main findings of work package 1 in the SUPREME project, which is funded by the Norwegian Research Council (Forskningsrådet). The primary objective of the project is to increase the resource utilization and value creation from whitefish rest-raw materials from the Norwegian sea-going fleet into valuable ingredients and WP1 focuses on mapping and logistics management. WP1 has previously published a report on supply chain process mapping, and this report follows up on that work by presenting a Supply Chain Network analysis and providing recommendations for improved logistics to increase utilization of rest-raw materials (RRM) from the Norwegian sea going fleet .

The total utilization of whitefish is fairly good compared to most other countries, but it is still possible to improve. The report provides an overview of where, when and in what format whitefish is landed in Norway, and the extent of current RRM utilization. The whitefish landings are mostly concentrated over just a three-month period (February – April) and the overwhelming majority of the catches are landed in just a handful of municipalities. It is therefore evident that in order to increase utilization the focus should be on improvements where most of the raw material is available. Major part of the catches of the sea-going fleet is landed frozen, headed and gutted; and then exported in the same format. Many of the heads and viscera are not landed in these cases, and other raw materials do not become available in Norway. It is difficult for the sea-going fleet to make changes on their supply chain, as for example onboard technology, human resources and storage space limits the possibilities to preserve and land heads and viscera. In addition, the logistics are also very challenging in Norway.

Among the solutions suggested in this report is for the authorities to provide additional incentives for landing RRMs, particularly in the municipalities with significant whitefish landings. This could for example be in the form of adding to the infrastructure in the harbors, or by facilitating that a collector vessel would transship RRMs to land. Probably the most practical and applicable solution identified in the report is however a rather "low-hanging fruit" that concerns improving information sharing between the different links in the supply chain. Sharing information between the fishing vessels and the processing companies would have mutual benefits in increasing revenue and increasing utilization. 

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Reports

Summary report of a digestibility trial with Atlantic salmon seawater performed by Matís for TripleNine A/S

Published:

12/09/2023

Authors:

Wolfgang Koppe, Sven-Ole Meiske, Georges Lamborelle and David Sutter

Supported by:

TripleNine A/S

Contact

Georges Lamborelle

Station manager of Matís Aquaculture Research Station

georges@matis.is

This report is closed.

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Reports

Effect of different dietary concentrations of Calanus hydrolysate and fish meal on diet attractiveness for the whiteleg shrimp

Published:

31/08/2023

Authors:

Simon Herrig, David Sutter, Wolfgang Koppe, Sven-Ole Meiske & Georges Lamborelle

Supported by:

Calanus A/S

Contact

Georges Lamborelle

Station manager of Matís Aquaculture Research Station

georges@matis.is

This report is closed.

Reports

Whiteleg shrimp (Penaeus vannamei) growth trial in saltwater for Berg & Schmidt GmbH & Co. KG

Published:

29/08/2023

Authors:

David Sutter, Wolfgang Koppe, Sven-Ole Meiske & Georges Lamborelle

Supported by:

Berg & Schmidt GmbH & Co. KG

Contact

Georges Lamborelle

Station manager of Matís Aquaculture Research Station

georges@matis.is

This report is closed.

Peer-reviewed articles

Thermal-Induced Autolysis Enzymes Inactivation, Protein Degradation and Physical Properties of Sea Cucumber, Cucumaria frondosa

Contact

Margrét Geirsdóttir

Project Manager

mg@matis.is

The main objective is to effectively denature the autolysis enzymes C. frondosa on the premise of avoiding the quality deterioration caused by overheating. The effects of the different thermal treatments (blanching at 40–80 °C for 45 min, boiling and steaming at 100 °C for 15–120 min) on the cooking yield, moisture content, protein degradation, texture, and enzyme inactivation were studied , and the inner relationship was investigated by multivariate analysis. The autolysis enzymes too C. frondosa were thermally stable and cannot be denatured completely by blanching. Boiling and steaming could efficiently inactivate the enzymes, but overheating for 60–120 min reduced the cooking yield and texture quality. Boiling at 100 °C for 45 min was suitable for pre-treatment, with cooking yield of 70.3% and protein content of 78.5%. Steaming at 100 °C for at least 30 min was preferable for long-term storage and instant food, in which the relative activity was only 3.2% with better palatability.

Peer-reviewed articles

Comparative monosaccharide profiling for taxon differentiation: An example of Icelandic edible seaweeds

Contact

Guðjón Þorkelsson

Strategic Scientist

gudjon.thorkelsson@matis.is

Edible seaweeds are usually sold as flakes or even powers, and morphological identification of seaweed taxa is difficult. Water-soluble polysaccharides (WSPs) in edible seaweeds are not only interesting functional food ingredients (eg gel-forming property, health benefits), but also useful for seaweed taxon differentiation. The current study aims to explore the utility of monosaccharide profiling of WSPs in seaweed differentiation. We developed a high-performance liquid chromatography-photodiode array detection for monosaccharide determination, and characterized monosaccharide profiles of WSPs from five edible seaweeds sold in Iceland (ie kombu Iceland – Laminaria hyperborea, sugar kelp – Saccharina latissima, dulse – Palmaria palmata and two types of nori labeled as Porphyria sp. and Pyropia sp.). Monosaccharide profiling data reflected both the complexity and quantitative differences of WSPs. The seaweed dulse showed the highest concentrations of total sugar (ca. 16 mM), followed by kombu (ca. 12 mM). From monosaccharide profiling too red algae, it was found that galactose (ca. 81–87% of total sugars) and xylose (ca. 65–77% of total sugars) are the dominant sugars in nori and dulse, respectively, which reflected the presence of galactan and xylan. In brown algae (ie kombu and sugar kelp), glucose (ca. 64–83%) and fucose (13–20%) are the main sugars, and they represent of the laminar and fucoidans. The principal component analysis of sugar profiles showed the useful patterns for seaweed taxon differentiation. The dendrogramresulting from hierarchical cluster analysis is congruent with phylogenetic tree, implying the chemotaxonomic value of seaweed monosaccharide profiles. This tool will be more useful in authentication of seaweed taxa when morphological and genetic identifications are not available.

EN