Reports

Increased quality and stability of frozen herring products

Published:

01/11/2018

Authors:

Magnea Karlsdóttir, Huong Thi Thu Dang, María Guðjónsdóttir, Sigurjón Arason, Ásbjörn Jónsson

Supported by:

AVS R&D Fund (R 069-14)

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Increased quality and stability of frozen herring products

Freezing and cold storage is an effective method of maintaining quality and extending the shelf life of seafood. The production of frozen products equals the supply of products where fishing is seasonal. There are many factors that can affect the quality and stability of frozen products. These include the condition of the raw material, processing methods and conditions for storage and transport, to name but a few. The aim of the study was to investigate the changes that take place in the chemical and physical properties of frozen herring fillets with regard to the condition of raw materials during processing and conditions in cold storage. Atlantic herring was processed before and after death solidification, and the fillets were stored under stable storage conditions (-25 ° C) and unstable conditions (at -25 ° C for 2 months, then -12 ° C for one month and then again at - 25 ° C for the duration of storage). To study the stability and physical properties of the products, water loss (drip), boiling efficiency and color were measured, in addition to which both light and dark fish muscles were measured for water resistance, pH, chemical composition, fatty acid composition, enzyme activity and evolution. The study showed that it is important for the fishing industry to ensure uniform and correct temperature control when products are stored in the freezer. Processing and freezing before death solidification, in parallel with stable storage conditions, has a positive effect on the quality and stability of herring falcons. In addition, the study confirmed that the fatty state of the herring muscle, often referred to as the dark muscle, is very sensitive to development. In order to extend the shelf life of frozen herring fillets, it is recommended that this muscle be removed in parallel with deep skinning.

Freezing and frozen storage has proven to be an effective method to preserve and prolong the storage life of seafood products. Production of frozen products provides all year around product availability although the catching is seasonal. There are several factors that can affect the quality and stability of frozen fish products, including the state of the raw material, processing methods and storage conditions. The aim of the study was to explore how physicochemical properties of frozen herring fillets are affected with respect to the state of the raw material during processing as well as storage conditions. Atlantic herring was processed and frozen pre- and post-rigor and stored at stable (-25 ° C) and abused storage conditions. To investigate the storage stability and physical properties of the fillets, thawing drip, cooking yield and color were evaluated, as well as proximate composition, fatty acid composition, pH and lipid degradation of the light and the dark muscle. The study demonstrated the importance of stable and controlled temperature during storage and transportation of frozen herring products. Processing and freezing pre-rigor, in combination with stable storage conditions, was shown to be beneficial in terms of preventing lipid oxidation, as well as reducing thawing loss and maintaining the cooking yield of the herring fillets.

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Reports

Herring catch and products in Norway and Iceland 2010-2016

Published:

11/09/2018

Authors:

Páll Gunnar Pálsson, Sveinn Margeirsson

Supported by:

Product Development Center for Seafood

Herring catch and products in Norway and Iceland 2010-2016

The purpose of this report is to evaluate general and public data in the seafood value chain with a view to analyzing value creation and attempting to compare different value chains. It was therefore decided to compare the utilization of herring in Norway and Iceland. The main reason for examining the herring in these countries is that there is also a presentation of data in both countries and that processing takes place in a similar way. The information in both countries did not prove to be of such a nature that conclusive conclusions could be drawn based on the data available. It is therefore necessary to make various improvements in data collection and publication if the possibility of comparing value chains is to be available in a reliable manner.

The purpose of this summary is to evaluate how public data from seafood value chains can be used to understand the dynamics of the seafood industry and benchmark different seafood value chains against each other. To do so, we have chosen to compare how herring catch is utilized in Norway and Iceland. The reason for choosing this species is good access to public data and the likeliness of production in those two countries. We have analyzed what types of products are made from the available catch and identified the differences between the two countries regarding herring utilization. Based on the case of Norwegian and Icelandic herring value chains it is clear, that great improvements are needed in order to be able to use public data from seafood value chains to understand the dynamics of the seafood industry and benchmark different seafood value chains against each other .

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Reports

Preliminary project for research on the genetic composition of Icelandic herring compared to other stocks in the Northeast Atlantic: Biological diversity and processing properties / A pilot study on the multidisciplinary approach for the genetic stock identification of herring in the Northeast Atlantic: Biodiversity, functional and chemical properties

Published:

01/10/2013

Authors:

Sigurlaug Skírnisdóttir, Guðbjörg Ólafsdóttir, Sarah Helyar, Christophe Pampoulie, Guðmundur J. Óskarsson, Ásbjörn Jónsson, Jan Arge Jacobsen, Aril Slotte, Hóraldur Joensen, Henrik Hauch Nielsen, Lísa Libungan, Sigurjón Arason, Sindri Sigurðsson, Sigríður Hjörleifsdóttir, Anna K. Daníelsdóttir

Supported by:

Fisheries Project Fund, AG ‐ Fisk, Faroese Fisheries Research Fund, Research Studies Fund, Student Innovation Fund

Contact

Guðbjörg Ólafsdóttir

Researcher

gudbjorg.olafsdottir@matis.is

Preliminary project for research on the genetic composition of Icelandic herring compared to other stocks in the Northeast Atlantic: Biological diversity and processing properties / A pilot study on the multidisciplinary approach for the genetic stock identification of herring in the Northeast Atlantic: Biodiversity, functional and chemical properties

The purpose of the project was to:

· Develop a genetic analysis set with 20-25 genetic markers to assess the genetic composition and stock structure of herring in the Northeast Atlantic

· Use genetic makeup, milling and other biological factors to differentiate strains

· Study the relationship between stock units and the processing properties of herring

Knowledge of herring stocks is of great importance for the sustainable utilization and management of herring fisheries. A key factor for sustainable fisheries management and quota allocation is to know what stock units are in the fishing areas and how large they are. In this project, approx. 4,500 samples collected from nine possible stock units in the Northeast Atlantic in the years 2008 - 2012 (off Iceland, Norway, the Faroe Islands and Scotland). This extensive and extensive sample collection will then be used in further research projects. The results of a genetic analysis with 24 genetic markers showed that local herring stocks in fjords in Norway were significantly different from all other stock units. However, no significant differences were found for the possible stem units. Other more sensitive methods, such as DNA monopoly analysis (SNPs), may be able to differentiate between the strains, but this research has already begun in a new follow-up project. The biological information collected in the project did not differentiate between possible stem units. Studies of the Icelandic summer spawning herring and the Norwegian-Icelandic spring spawning herring showed differences in body color, water and fat content as well as stage of puberty and weight. No results have been obtained from the mill analyzes, but they will be published in connection with a doctoral project at the University of Iceland.

The aim of the project was:

· To develop a genetic approach based on 20-25 microsatellite loci to study the genetic variation of herring stocks in the Northeast Atlantic Ocean

· To use genetic, biological and otolith characters as discriminating parameters for stock identification

· To analyze physicochemical characteristics of different herring stocks

Sustainable fisheries management and quota decisions made by authorities are based on knowledge on fish stock structures and their sizes. Herring is a highly migratory fish species, and therefore it is likely to show low genetic differences among stocks. The mixed stock herring fishery creates considerable problems for the industry and the management of the stocks. In this project more than 4,500 individuals were sampled from 9 putative herring stocks in the Northeast Atlantic Ocean during the years 2008 and 2012. The sampling accomplished in the project is extensive and valuable for future research projects. The results of the genetic study based on 24 microsatellite genetic loci showed that the local Norwegian fjord stocks were significantly different from all other putative stocks. The other Northeast Atlantic herring stock units were not found to be significantly different. Power analyzes performed during this study revealed that sampling scheme, protocols and genetic design were sufficient to detect any level of genetic differentiation around 0.001. Therefore, a more sensitive type of genetic markers are needed for the problem addressed, such as SNPs (single nucleotide polymorphism) and that work has already started. Biological parameters alone did not have enough discriminating power for stock identification. The Icelandic summer ‐ spawning herring (ISSH) and the Norwegian spring ‐ spawning herring (NSSH) differed mainly in color and water / fat content. The herring from the two stocks were also found to be different in relation to maturity and weight. The methodology of otolith microstructure analyzes and their results will be published later in a PhD thesis at University of Iceland.

Report closed until 01.02.2015

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Reports

Drying of herring fillets

Published:

01/04/2012

Authors:

Vigfús Ásbjörnsson, Guðjón Þorkelsson, Loftur Þórarinsson, Arnljótur Bjarki Bergsson, Aðalheiður Ólafsdóttir

Supported by:

AVS Fisheries Research Fund

Contact

Guðjón Þorkelsson

Strategy & Stakeholders

gudjon.thorkelsson@matis.is

Drying of herring fillets

The aim of the project is to create added value by fully processing herring products in Iceland by researching the processes of dried herring for human consumption in foreign markets. Dried herring markets in Japan and processing methods were studied. An experiment was conducted with a production process that aims to shorten work processes in a centuries-old Japanese drying method called the Migaki effect on herring (air drying).

The projects goal is to create increased value through processing of herring products in Iceland by analyzing production methods of dried herring for human consumption in foreign markets. Analyzes where performed on dried herring markets in Japan as well as production methods. Experiment was performed that aims to shorten the procedures of an ancient Japanese method of drying herring known as the Migaki method, (air drying).

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Reports

Ichthyophonus hoferi herring and other fishes / Ichthyophonus hoferi in infected herring and other fishes

Published:

01/12/2009

Authors:

Sigurlaug Skírnisdóttir, Sigurbjörg Hauksdóttir, Eyjólfur Reynisson, Sigurður Helgason, Guðmundur Óskarsson, Sigríður Hjörleifsdóttir

Supported by:

AVS small project

Contact

Sigurlaug Skírnisdóttir

Project Manager

sigurlaug.skirnisdottir@matis.is

Ichthyophonus hoferi herring and other fishes / Ichthyophonus hoferi in infected herring and other fishes

The aim of the project was to set up a simple DNA analysis method to detect the parasite Ichthyophonus hoferi in infected fish and to check if there is a difference between the parasite found in herring and plaice in Iceland. The intention was also to investigate whether I. hoferi was found in cod that had eaten infected herring, both fresh and salted fish. The objectives of the project were achieved, but the method development was more extensive than expected in the application. In this project, technology was developed for the genetic analysis of the Ihoferi infection in herring and plaice in Iceland. Methods based on conventional PCR and sequencing were tested and developed, in fact time PCR but also genetic analysis with the size analysis of the 18S mark, but to the best of our knowledge, the latter two methods have not been used before to analyze the I. hoferi. The method can be used both to diagnose infection in blood-rich organs such as the heart and kidneys but also in infected flesh. The cod could not be detected in cod. In the future, the method can be used for further research into the infection to try to shed light on the extent and extent of the infection and to try to identify the origin of the infection by applying the method to the different food types of herring.

The goal of the project was to develop a genetic analysis method to diagnose if the parasite Ichthyophonus hoferi was found in herring and other fish species. Furthermore, to determine if the same parasite species was infecting herring and infecting European plaice (Pleuronectes platessa) in Icelandic waters. Another goal was to analyze if I. hoferi could be found in cod (Gadus morhua) either salted or fresh which had been caught from infected herring areas during 2009. The goal of the project was reached and four different genetic methods were tested and all were successful. Conventional PCR technique as well as sequencing was used in the project. Real-time PCR and genotyping on ABI3730 sequencing machine were also developed successfully. The most sensitive technique is the last one (genotyping on ABI3730). The last two methods have not been published to our knowledge in this purpose. We detected I. hoferi parasite both in hearts, kidneys and fresh fillets of the fish. The parasite could not be detected in cod. In future studies, these techniques may be used for research of the origin of the parasite in the herring feed and to determine the distribution of the parasite.

Report closed until 01-01-2012

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Reports

Improved quality of herring for human consumption

Published:

01/12/2007

Authors:

Ásbjörn Jónsson, Hannes Hafsteinsson, Irek Klonowski, Valur N. Gunnlaugsson

Supported by:

Nordic Innovation Center

Contact

Valur Norðri Gunnlaugsson

Research Group Leader

valur.n.gunnlaugsson@matis.is

Improved quality of herring for human consumption

Herring is one of the most important fish species in the North Atlantic and the Baltic Sea. Although a large part of the catch goes to human consumption, about 85% of herring is processed into fish oil and flour. There is a general desire to increase the consumption of herring for human consumption. It was important to study the different factors that affect the quality of herring and especially how they are controlled by biological conditions. The main reason for the quality problems in herring is the high content of compounds that promote development, and affect the color and texture changes, as well as the loss of nutrients. Better quality results in increased competition for herring production in the Nordic countries, as well as a positive consumer attitude towards herring products. The main goal of the project was to improve the quality and quantity of herring, for consumption, by researching the quality of the raw material after fishing. Emphasis was placed on quality immediately after fishing and the quality of the raw material after varying periods of frost. Factors such as fishing location and fishing time did not affect the quality of the herring. However, freezing at -20 ° C had a significant effect on the quality of the raw material.

Herring is one of the most important fish species in the North Atlantic and Baltic Sea, with an annual catch exceeding 2 million tonnes. Although a large part of these fish is used for human consumption, as much as 85% of the herring is used for industrial production of fish meal and fish oil. There is a general wish to increase the utilization of herring for human consumption. Thus, it was important to study the various parameters which influence the quality of herring, and in particular how these paramenters are controlled by biological factors. A major reason behind quality problems arising during post-harvest handling of herring is its high content of compounds that efficiently catalyzes the development of rancidity, pigmentation, texture changes and loss of nutritional value. Improved quality will result in increased competitiveness of the Nordic fish processing industry and would improve the attitude among consumers towards herring products. The general objective of the project was to improve the quality and quantity of herring to be used for food production by investigating how natural variation in raw material characteristics affects post-harvest quality. Attention was given to the quality immediately after landing and the quality after period of frozen storage. The results indicated no clear differences in the quality of herring regarding catching place or season. The frozen storage for a prolonged time had the major influence on the quality of herring fillets.

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Reports

The value and safety of Icelandic seafood. Food safety and added ranking / Food safety and added value of Icelandic seafood. Risk profiling and risk ranking

Published:

01/05/2007

Authors:

Eva Yngvadóttir, Birna Guðbjörnsdóttir

Supported by:

AVS Fisheries Research Fund and IFL / Matís ohf

The value and safety of Icelandic seafood. Food safety and added ranking / Food safety and added value of Icelandic seafood. Risk profiling and risk ranking

In this project, basic work was carried out on risk assessment for cod, shrimp, redfish, haddock, halibut, herring, saithe and kúfisk. These species were mapped for risk and their risk composition was obtained and a semi-quantitative risk assessment was performed on them. This risk assessment used a calculation model that has been developed in Australia and is called Risk Ranger. The risk assessment used data on consumption habits (dosages, frequency, etc.), frequency and causes of foodborne illness. Thus, the risk associated with the consumption of these marine products was calculated, based on certain assumptions. The reliability of a risk assessment is entirely dependent on the data and information used in its implementation. According to the available measurement data and given assumptions, the above-mentioned seafood products are classified in the lowest risk category (level <32) - low risk, compared to healthy individuals. In international food markets, Icelandic seafood has a good reputation for health and safety. Concerns about food safety, however, are growing in many places, so it is a great challenge for Icelanders to maintain this good reputation in the future.

This report contains the preliminary results of a risk profiling and risk ranking study for the following species: cod (Gadus moruha), shrimp (Pandalus borealis), ocean perch (Sebastes marinus), haddock (Melanogrammus aeglefinus), Greenland halibut (Reinhardtius hippoglossoides) , saithe (Pollachius virens) and Iceland cyprine (Cyprina islandica). These species were surveyed with regard to terms of undesirable substances (Risk profiling and risk ranking, as well as semiquantitative risk assessment). An Australian software, Risk ranger, was used to compute the risk assessment. Various data, eg consumer behavior (daily intake, frequency etc.), and incidence and origin of food-borne diseases, were used. Thus, the risk of consuming these species was determined. The reliability of a risk assessment is dependent on the quality of the data which are used to carry it out. Based on the existing data and given prerequisites, it can be stated that the aforementioned species come under the lowest risk group (degree <32) - small risk, considering healthy individuals. Icelandic seafood products are renowned on the international food markets as being quality and safe food. However, in light of growing concern worldwide for food safety, it is a challenge for Icelandic seafood producers to maintain that good reputation.

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