Reports

New technology to increase the value of catfish catches

Published:

01/07/2018

Authors:

Gunnar Þórðarson, Sigurjón Arason

Supported by:

AVS Fisheries Research Fund (R 025-11), Rannís

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

New technology to increase the value of catfish catches

The purpose of the project was to adapt processing to supercooled raw materials, to ensure the homogeneity of raw materials with the aim of improving product quality, increasing utilization and minimizing fillet defects. In the project, a new type of skinning machine was developed and then tested under real conditions. Comparison of supercooled and traditional (frozen) ingredients. Supercooled raw material is stiffer than conventional, and the same can be said for fillets cooled after filleting to ensure packing in fresh packages at low temperatures, preferably below 0 ° C. Traditional skinning machines have not been able to handle such raw material, but the new machine has already been put into use and is proving successful. A comparative experiment was carried out between super-chilled haddock that was six days old and traditional raw material from the same catch. Subsequently, a comparative study was conducted on cod, made from super-chilled and conventional raw materials. Utilization, fillet quality and defects were compared, as well as product division after cutting into fillet pieces, as well as temperature processes during processing in both groups. The results were very good for supercooled raw materials, both in terms of quality, utilization and temperature of products.

The purpose of the project was to customize processing of sub-chilled raw materials to ensure uniformity of raw materials with the aim of improving product quality, increasing utilization and minimizing fillet defects. A new skinning machine for demersal fish was designed and tested in this project, especially to work with sub-chilled raw material. Sub-chilled raw material is more rigid than traditional raw material and can withstand more handling and give better quality of the finished product. Sub-chilled raw material also provides lower product temperature in packed fresh fish production, at 0 ° C or even below it. Traditional skinning machines have not been able to handle sub-chilled fillets. A comparative experiment with six-day old haddock where sub-chilled raw material were compared with traditional one, from same catch, were processed. Built on that outcome a follow-up, a comparative study of cod was processed with sub-chilled and traditional raw material. In both experiments a comparison of yield, fillets quality, fillets defects and temperature throughout the production into final packaging were recorded. The results were excellent in favor of sub-chilled raw material, both in terms of quality, yield and temperature of products.

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Reports

Sub-chilling of salmon

Published:

01/12/2015

Authors:

Gunnar Thordarson, Magnea Karlsdottir, Roger Pedersen, Magnus Johannsson, Albert Hognason

Supported by:

Norwegian Research Council

Contact

Gunnar Þórðarson

Regional Manager

gunnar.thordarson@matis.is

Sub-chilling of salmon

The aim of the project was to increase the quality of fresh salmon production, by improving the cooling chain during production and transport. By using supercooling methods, salmon producers will be able to reduce their production costs due to lower transport costs and at the same time improve the quality of production. The salmon was cooled to -1.5 ° C which increased the lifespan and quality of the product. In addition to improving production during slaughter, gutting and packaging, supercooling can also create opportunities for further processing; filleting, smoking, chopping, etc. to improve their production through increased utilization and value along with happier customers. Among other things, supercooling makes it possible to transport the refrigerant into the fish flesh instead of using ice for transport. The project compared the cooling chain of super-chilled salmon with conventional. The former was transported without ice but the traditional one with ice, for further processing in Finland and Norway. Such a comparison was also made between super-chilled and traditional salmon that was transported to Iceland via Oslo on the one hand and to Tokyo via Oslo on the other. The results give rise to optimism about the use of supercooling in the salmon transport chain, both to reduce transport costs and to ensure product quality.

The ultimate goals of the project was to increase quality of fresh salmon products, provide a more secure cold chain of fresh product, and lower production and logistic costs. Having the fish in a sub-chilled state throughout the production, will give Grieg Seafood several quality advantage including firmer raw material and lower bacteria and enzyme activity in the fresh fish. Fish was packed in a sub-chilled state of -1.5 ° C, hence extending shelf-life and quality. This will have several advantages for the primary producer, resulting in products with higher yield and more value, and in products of higher quality for their customer of secondary processing. Secondary processors will have better control of the product logistic and extended time for selling fresh product with longer shelf-life. Using the sub-chilling method, no ice will be needed during logistic, saving enormous transportation costs, especially in airfreight. Comparison between the cold-chain of sub-chilled and traditional produced salmon was executed in this project, with the former transported without additional ice. The salmon was trucked from Simanes to a secondary processors in Finland and Denmark with excellent result. The two groups were also flown to Iceland, via Oslo, and also to Tokyo via truck to Oslo. The result of this comparisons demonstrates that the sub-chilling method could be used to minimize transportation cost and secure the product quality during logistics.

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