The difference between wild and farmed salmon production was successfully profiled and differentiated
New tool for identifying wild and farmed salmon
Wednesday, November 29, 2023, 07:00 (GMT + 9)
Thanks to new analysis techniques, researchers can distinguish between farmed salmon and wild Atlantic salmon on a large scale. Does this make cheating salmon a thing of the past?
The price of wild salmon is higher than that of farmed salmon, which makes salmon an attractive fish for fraud. Consumers today are much more concerned with where their food comes from and choose animals that have had a good life. That makes wild salmon more attractive to them.
There are differences between the two salmon species not only in terms of life. There are also differences in nutritional value. Wild salmon contains more omega-3 fatty acids and minerals such as zinc, magnesium, iron and potassium.
PCA results. (a) PCA score plot between PC1 and PC2 for 5 groups of salmon samples (b) Scree plot. (c) PCA Plot of PC1 and PC2 for five salmon groups differentiated by wild (yellow) and farmed (green) production type. (d) PCA plot of PC1 and PC2 between wild and farmed salmon groups. (e) Data distribution between wild-type and farmed salmon group in PC1, PC2, and PC3. (f) Loading plot of PC1 and PC2. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) .Click image to enlarge
The difference is clearly visible with whole salmon. Farmed salmon has a pink/orange color while the wild variety is redder. This is due to the difference in nutrition. Wild salmon feed on krill and crustaceans that contain the antioxidant astaxanthin, which causes the red color. Farmed salmon do not ingest this substance. In addition, farmed salmon is larger. These continue to grow because there is always food available. With salmon moths it is much more difficult to see that difference. Although there are various analysis methods for this, they are not suitable for testing salmon on a large scale.
Metabolic profiling and univariate analysis results: (a) the correlation heatmaps of these 426 salmon samples. (b) Heatmap of top 20 features in salmon samples among 5 groups. (c) Box plots of top 20 significant metabolites according to ANOVA. Click image to enlarge
In a new study, a group of international scientists, including from Wageningen University & Reseatch, present the results of a new analysis technique that combines advanced lab techniques with smart statistical tools. They managed to correctly analyze 426 pieces of salmon and call the method 100 percent reliable for distinguishing between farmed and wild salmon. The researchers therefore believe that they can eliminate cheating salmon with this new analysis method.
Source: vismagazine.nl | Food Chemistry/WUR (translated from original in dutch)