Sub-chilling of salmon




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

Supported by:

Norwegian Research Council


Gunnar Þórðarson

Regional Manager

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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