Stunning Salmon - With a Focus on Welfare and Quality

Meeting in Tromso, 18 September, saw approximately 60 people from salmon slaughterhouses, aquaculture, scientists, fisheries and equipment. There was great enthusiasm, and participants shared experiences and knowledge.

Although most salmon slaughterhouses has anesthetic and killing systems that work very well, there are still problems that are not solved. The industry reports that the residual blood in the gills and the fish is a growing challenge. This is an element that can affect the quality and shelf life of the fish. A controlled or optimised flow of fish through the slaughter line were seen as the most important for maintaining good welfare and quality.

Experiences from the use of electricity anesthesia has shown that uniformity of fish - ie head first - is important, and works well as it is now. Problems with blood spots are practically gone after the plants were built. For the use of electrical anesthesia, researchers recommend the use of voltage of 110 volts with a contact time of five seconds as a good practice.

Good fish welfare is a prerequisite for the success of impact machines, which give positive effects if one wants pre-rigor filleting.

FSA stressed that it is up to the users to document fish welfare during live chilling and that one can refer to reputable sources. There may be a need to study the cooling of live fish because of the new requirement that the temperature should be below 2C at delivery. Such a low temperature can be difficult to achieve without the fish being well cooled before slaughter.

The alternatives to anesthesia with CO2 are now in place in a majority of slaughterhouses. Some butchers still use CO2, but they are all in the process of installing new solutions. At the meeting in Troms, it emerged that there have been major challenges for those using the new technology, but that it should be possible to achieve proper stunning and slaughter at all facilities.

It is also encouraging to note that there is a high degree of agreement between what industry, equipment suppliers, veterinarians, FSA and researchers think about the status of slaughter.

"This was a very important meeting between industry, research and Research," says Nofima researcher Torbjrn Tobiassen.

"There is need for more such meetings in the future, providing the opportunity for networking and exchange of experience. We therefore expect that such meetings are here to stay," says the researcher.