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.

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Reports

Experiments with the processing of sea urchin eggs

Published:

01/06/2013

Authors:

Jón Trausti Kárason, Ragnheiður Sveinþórsdóttir, Kolbrún Sveinsdóttir, Guðmundur Stefánsson, Sæmundur Elíasson, Stefán Freyr Björnsson, Aðalheiður Ólafsdóttir, Irek Klonowski, Ragnar Jóhannsson

Supported by:

West Iceland Growth Agreement

Contact

Kolbrún Sveinsdóttir

Project Manager

kolbrun.sveinsdottir@matis.is

Experiments with the processing of sea urchin eggs

In this project, three experiments were performed with different goals. The aim of the first experiment was to examine the quality of sea urchin eggs and to test the rapid freezing of eggs with exports in mind. In the second experiment, branched dextrin sugars (Glico) and alginate were used to strengthen the outer layer of the eggs, the purpose was to find a substance that could replace alum to keep the eggs better from processing to the buyer. In the third experiment, the aim was to investigate whether it was possible to process sea urchin roe by heat treatment as a bulk product and also whether it was possible to separate the processing in time, ie. whether the pots could be opened and the roe packed in larger units so that they could be handled elsewhere than where the pots were opened.

In this project three experiments were undertaken. The goal in the first one was to explore the quality of gonads (sea urchin roes) and try to instant-freeze it for export. In the second experiment clusterdextrin and alginate was used to make the surface of the roes stronger. The purpose of that experiment was to find a substitute for alum for the gonads to keep their shape during the time from processing to buyer. In the third experiment the goal was to explore if it was possible to process gonads with heating in a large quantity and if it was possible to separate the stages of processing so tha the gonads could be collected and packed in one location, then further processed in another.

Report closed until 01.07.2016

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Reports

Full processing of mackerel

Published:

01/10/2011

Authors:

Ásbjörn Jónsson, Ragnheiður Sveinþórsdóttir

Supported by:

AVS Fisheries Research Fund

Full processing of mackerel

The main objective of the project was to develop valuable products for human consumption from mackerel caught by pelagic vessels as well as to assess the profitability of such processing. Mackerel products for human consumption are much more valuable than products from fishmeal processing and there are great interests in processing for human consumption, such as canning and hot smoking. Experiments were carried out with the processing of mackerel in canning. Mackerel was boiled in tomato puree and smoked and boiled in oil. There was also an experiment with hot smoking of mackerel. The efficiency of such processing was done together with a sensitivity analysis, based on a yield of 13%. Positive results of experiments with mackerel processing in canning and hot smoking, together with a profitability assessment of such processing, indicated that such processing was profitable in the long run.

The main objective of this project was to develop valuable products from mackerel for human consumption together with evaluation of profitability of such processing. Mackerel products for human consumption are more valuable than products from oil and meal processing. Trials were done on processing mackerel products from canning in oil and tomato puree, and hotsmoking. Profitability of such process was evaluated with IRR (internal rate of return) of 13%. Favorable results of the project indicated that processing of canned and smoked products could be profitable in the long ‐ term.

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Reports

Development of a process for enzyme treatment of liver before canning

Published:

01/09/2009

Authors:

Ásbjörn Jónsson, Irek Klonowski, Sigurjón Arason, Sveinn Margeirsson

Supported by:

AVS Fisheries Research Fund

Contact

Sigurjón Arason

Chief Engineer

sigurjon.arason@matis.is

Development of a process for enzyme treatment of liver before canning

The aim of the project was to increase the value and utilization of liver for canning, by developing a process and processing pathway for enzyme purification in the membrane of the liver to release roundworms located on the surface of the liver. Furthermore, the aim was to develop a method and equipment for brine salting for canning. The results and benefits of the project consisted of the development of a technology with enzymes that is effective in releasing membrane and ringworm on the surface of the liver for canning. Processing speeds increased and utilization increased from 60% to 80-85%. The investment is considered profitable and the return on total investment (ROTA) returns within a few years.

The aim of this project was to increase the profitability in the production of canned liver, by developing a process to remove the ringworms from the membrane at the surface of the liver with enzymes, before canning. Furthermore, to develop a process for brining of liver before canning. The yield and the profit of the project consisted of a development of a technique with enzyme which successfully remove membrane and ringworms from the surface of the liver before canning. The efficiency of production increased along with the yield from 60% to 80‐85%. The investment is profitable and the return on total asset will be in a few years.

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