Tag: Pelagic fish

Reports

Process control of pelagic fish crude oil / Process control of pelagic fish crude oil

Published:

01/10/2018

Authors:

Magnea G. Karlsdóttir, Sigurjón Arason

Supported by:

AVS Research Fund (S 010-15)

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Process control of pelagic fish crude oil / Process control of pelagic fish crude oil

The aim of this preliminary project was to analyze different currents in fishmeal and fish oil processing of pelagic species. Emphasis was placed on analyzing the fatty acid composition of liquids at different points in the liquid separator. It is believed that the product of the project can lead to improved production of pelagic fish body oil, as it will be possible to produce fish oil with different proportions of polyunsaturated fatty acids (such as EPA and DHA). By extracting the fish oil from different liquid streams, fish oil can be obtained with different properties and thus increase the value of fish oil products produced in fishmeal and fish oil factories. Significant variability in the fatty acid composition was measured in the samples, both by fish species and at the sampling site. The samples all had in common that monounsaturated fatty acids were in the majority independent of fish species and sampling site. Polyunsaturated and saturated fatty acids followed. There was evidence that the longer polyunsaturated fatty acids degrade as the process progresses. With improved processing processes, it would be possible to start producing high-quality fish oil products for human consumption. It is therefore necessary to go into a much more detailed analysis of the whole process, but the results of this project indicate that there is still a long way to go.

The objective of the project was to identify different streams during production of fishmeal and oil from pelagic fish. Emphasis was placed on analyzing the fatty acid composition of streams collected at different processing steps. It is believed that the results can lead to improved production of pelagic fish oil, since it will be possible to produce fish oil with various proportions of polyunsaturated fatty acids (such as EPA and DHA). Considerable variability was observed between the collected samples, both by species as well as where in the process the samples were collected. Monounsaturated fatty acids were majority in all the samples, regardless of fish species and sampling location. Moreover, the results indicated that the longer polyunsaturated fatty acids can break down as the process goes further. With improved processing control, it is possible to produce high quality oil products intended for human consumption. A comprehensive analysis on the entire process is however necessary.

Report closed until 01.11.2020

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Reports

Effect of brining and frozen storage on physicochemical properties of well-fed Atlantic mackerel (Scomber scombrus) intended for hot smoking and canning

Published:

01/12/2015

Authors:

Paulina E. Romotowska, María Gudjónsdóttir, Magnea G. Karlsdóttir, Sigurjón Arason, Ásbjörn Jónsson, Hörður G. Kristinsson, Telma B. Kristinsdóttir

Supported by:

AVS Fisheries Research Fund (R 040-12)

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Effect of brining and frozen storage on physicochemical properties of well-fed Atlantic mackerel (Scomber scombrus) intended for hot smoking and canning

Mackerel (Scomber scombrus) is a relatively new species off the coast of Iceland. As mackerel is a fatty fish with a short shelf life, it therefore requires maximization of storage conditions and processing processes. In this project, changes in the chemical and physical properties of the heat treatment of salted and unsalted mackerel were studied. Prior to processing, the fish was stored for 6, 9 and 12 months at -18 ° C and -25 ° C with a view to examining how well Icelandic frozen mackerel is suitable as a raw material in canned and hot-smoked products. To examine the effect of heat treatment on the processing properties of mackerel, the samples were heated to 75 ° C (to simulate smoking) and 90 ° C (to simulate canning). Prolonged storage in the freezer had a negative effect on the raw material due to increased development and the fish stored at -18 ° C had a significantly poorer quality compared to fish stored at -25 ° C before processing. The results showed that a product heated to 75 ° C had a higher water content, higher water resistance and higher utilization and was also higher compared to a product heated to 90 ° C. Overall, the results indicate that a fat summer marker could be well suited for the processing of canned and hot-smoked products.

Atlantic Mackerel (Scomber scombrus) is a novel species in Iceland and as a fatty fish with a short shelf-life it requires optimization of storage and processing conditions. Physicochemical changes of brined and un-brined mackerel were analyzed during frozen storage (6, 9, 12 months) at -18 ° C vs. -25 ° C with the aim of investigating the suitability of using well-fed frozen mackerel as raw material for canned and hot-smoked products. Heat treatments to a core temperature of 90 ° C (representing canning) and 75 ° C (representing hot-smoking) were applied. Prolonged frozen storage showed negative effects on the raw material prior to heat processing due to an increased level of lipid oxidation, where fish stored at -18 ° C was of significantly poorer quality than fish stored at -25 ° C. Moreover, the results indicated that heat treatment resulting in a core temperature of 75 ° C showed higher water content, liquid holding capacity, heating yield as well as lower maximum shear force of texture compared to mackerel heated to a core temperature of 90 ° C. Overall, analyzes indicated that the fatty summer mackerel was well suited for the production of canned and hot-smoked products.

Report closed until 01.01.2018

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Reports

Short Training Course on Quality Assurance and Processing in the Artisanal Pelagic Fisheries Sector Tanzania June 18th to 29th 2012 / Practical course in quality assurance and processing for pelagic coastal fishing areas in Tanzania June 18-29, 2012

Published:

01/09/2012

Authors:

Margeir Gissurarson

Supported by:

UNU-FTP

Contact

Margeir Gissurarson

Strategic Scientist

margeir.gissurarson@matis.is

Short Training Course on Quality Assurance and Processing in the Artisanal Pelagic Fisheries Sector Tanzania June 18th to 29th 2012 / Practical course in quality assurance and processing for pelagic coastal fishing areas in Tanzania June 18-29, 2012

Matís held two practical courses in Tanzania for the United Nations University (UNU-FTP), in collaboration with the Ministry of Livestock and Fisheries Development Tanzania. Quality loss from fishing and processing in Tanzania is estimated at around 60% of landed catch. The main cause of the loss is inadequate handling and primitive production methods of pelagic fish (Dagaa). The content of the courses held in Mwanza and Kigoma dealt with improved safety and processing of marine products with an emphasis on pelagic fishing. In each course the number of participants was around 30.

Two short training courses were conducted in Tanzania by Matis for the United Nations University - Fisheries Training Program (UNU-FTP) in co-operation with the Ministry of Livestock and Fisheries Development in Tanzania. Post-harvest losses in fisheries in Tanzania are estimated to be around 60% of the total catch. These losses are mainly due to improper handling and poor processing techniques of the pelagic species (Dagaa). The courses held in Mwanza and Kigoma, covered the topics of fish safety and processing with emphasis on pelagic fisheries. About 30 persons participated in the course at each location.

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Reports

Increased value of pelagic species - FINAL REPORT / Increased value of pelagic species

Published:

01/05/2011

Authors:

Lárus Þorvaldsson, Björn Margeirsson, Ásbjörn Jónsson, Sindri Sigurðsson (SVN), Ásgeir Gunnarsson (SÞ), Sigurjón Arason

Supported by:

AVS Fisheries Research Fund

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Increased value of pelagic species - FINAL REPORT / Increased value of pelagic species

The main objective of the project Increasing the value of pelagic fish - improved refrigeration technology, which began in June 2008, was to lay the foundations for a new method of cooling and storing pelagic fish on board seiners. The result of improved cooling is that a higher proportion of the catch is useful for human consumption. Partners in the project were Matís, Síldarvinnslan (SVN) and Skinney Þinganes (UN). This report describes the main results and products of the project. Examples of products are heat transfer models of pelagic catches in ships and storage tanks on land and the integration of heat transfer models and quality forecast models, which make it possible to predict the quality of raw materials based on environmental temperature history. Heat distribution in pelagic vessel loads with different versions of cooling systems was mapped and storage temperatures were linked to quality measurements made during landing. From temperature and quality measurements it is clear that the frequency of defects in landed catch increases with increasing storage temperature. The main advantage of the MCS (Mixed Cooling System) cooling system, which combines CSW (Chilled Sea Water) and RSW (Refrigerated Sea Water) cooling systems, is that the system can reduce the inevitable temperature rise that occurs in a pre-cooled vessel following the pumping of catch in lestina. During the project, the Icelandic mackerel fishery was the largest and it can be stated that the results of the project have been used very well to improve the results of food processing of mackerel in this country and thus increase the product prices of a valuable species.  

The main aim of the research project Increased value of pelagic species - improved chilling methods, which was initiated in June 2008, was to develop a new method for chilling and storing pelagic species on board purse seiners resulting in more valuable products. This report describes the main results and products of the project. Examples include heat transfer models of pelagic fish stored in a ship hold and a storage tank onshore and coupling of the heat transfer models and quality forecasting models, which makes it possible to predict spoilage of pelagic species as a function of ambient temperature history. Temperature distributions in ship holds with different cooling systems were mapped and storage temperature related to quality measurements conducted during landing. The fault ratio of landed raw material clearly increased, indicating lower quality, with higher storage temperature. The main advantage of a mixed cooling system (MCS), which combines RSW and CSW systems, compared to using only RSW is a lower temperature increase in a precooled ship hold caused by loading the catch in the hold. During the project, the emphasis on mackerel fishing increased significantly around Iceland. It can be stated that the results of this project have been widely exploited in order to improve the yield of the mackerel and thereby increase the profitability of that valuable species.

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Reports

CFD Modeling and Quality Forecasting for Cooling and Storage of Pelagic Species

Published:

01/04/2009

Authors:

Lárus Þorvaldsson, Björn Margeirsson, Sigurjón Arason

Supported by:

AVS Fisheries Research Fund, Byggðastofnun

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

CFD Modeling and Quality Forecasting for Cooling and Storage of Pelagic Species

In the project, a computerized thermal and hydrological model of storage tanks for pelagic catches is built. The input of the model is time-dependent ambient temperature, which in turn returns the temperature distribution of the mixture of pelagic catches and seawater stored in the tanks. That model is such an intertwined quality forecast model that indicates the development of damaging substances such as TMA and NH3 based on the temperature history obtained from the thermodynamics model. The main result of the project is the development and application of technology that makes it possible to predict the damage processes of pelagic catches at a given environmental temperature history. This technology could prove to be extremely useful in the handling and processing of pelagic catches. Collaborating companies in the project are Síldarvinnslan, Skinney‐ Þinganes and HB Grandi.

In this project a thermodynamic model of storage tanks used for cooling and storage of pelagic species is constructed. The input for the model is transient ambient temperature, which gives the temperature and velocity distribution in the mixture of pelagic species and seawater. This model is then coupled with a quality forecast model, which predicts the development of spoilage indicators such as TMA and NH3 from the temperature time series which are retrieved from the thermodynamic model. The main result of the project was the development and application of a technique which makes it possible to predict the spoilage of pelagic species given only ambient temperature history. This could prove immensely useful in the management and processing of pelagic species. The following companies take part in this project: Síldarvinnslan, Skinney ‐ Þinganes and HB Grandi.

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