Q01031: Development and validation of methodology for the confirmation of the origin of wild and farmed salmon and other fish
Thursday 28 August 2003
This research project produced validated methodology for authenticating wild and farmed salmon to allow independent verification of labelling claims.
Study Duration: September 2001 to August 2004
Contractor: EC consortium with Eurofins Scientific as overall co-ordinator
Background
There has been growing interest in the nutritional benefits of fish. The subsequent increase in demand for fish in the face of declining natural fish stocks has led to the development of aquaculture and the ready availability of farmed fish - particularly salmon in the UK. This development has led to a significant reduction in the cost of salmon and farmed fish is two to three times cheaper than wild salmon. Wild salmon, however, is still held by many to be superior eating compared to farmed fish and, given the price difference, there is the temptation to mislabel farmed fish as “wild”. It is also a possibility that geographic origin may be mislabelled, for example fish farmed in the UK labelled as “Scottish Salmon”.
Planned changes to the Fish Labelling Regulations will require the catch area and production method (ie farmed or wild) to be clearly labelled. It is therefore necessary to produce validated methodology for the purpose of authenticating wild and farmed salmon to allow independent verification of labelling claims.
Research Approach
This research involved the use of a range of isotopic and compositional analyses to establish markers to authenticate the production method and geographical origin of salmon. A large number of samples from each of the important groups from major importing countries (e.g. farmed/wild salmon from Scotland, Norway, Canada etc) were obtained and analysed in order to create a database and establish a fingerprint for each group. Factors studied include effects of geographical location, age of fish, diet, time of year, freshness and cooking on analytical parameters identified.
Results and findings
The results have shown that using the stable isotope measurements of the fish oil in combination with the fatty acid composition of the fish enables clear differentiation between wild and farmed salmon. A blind trial was undertaken to validate the developed method. Preliminary studies using other fish types, namely cod, sea bass and halibut also undertaken in this project revealed promising results.