Variation in some quality attributes of Atlantic salmon fillets from aquaculture related to geographic origin and water temperature

It is well know that factors like fat content and texture affect the yield when making products from Atlantic salmon (Salmo salar L.). The relation between these factors and other quality attributes like water holding capacity and protein content, however, has received limited attention. To enable an efficient use of the information gathered in the different links of the value chain, a deeper knowledge of the correlations between the various quality attributes and factors like the geographical origin of the salmon, the company and the water temperature of the fish farm, is needed. In the present study a multivariate approach was taken to investigate the variation in some quality parameters (fat, protein, texture, water holding capacity, weight) amongst salmon samples (n = 136) from Norwegian aquaculture in order to establish which parameters were accounting for most of the variation seen in relation to the geographical origin and thereby of the sea temperature at harvest. The protein content of farmed Atlantic salmon sampled at different times of year varied substantially and was significantly correlated to the sea temperature. Fat and water content were also negatively correlated yet the correlation coefficient was numerical lower than what is usually seen in fatty fish, which could be a consequence of the varying protein content. A variation in both texture and water holding capacity was observed between the rearing companies. The present study adds to the existing knowledge regarding texture differences and contributes with new knowledge about the proximate composition of Atlantic salmon from aquaculture. Moreover we show that analysing different parameters holistically may reveal a new dimension in the information regarding differences between companies and regions in relation to the final quality of the filleted salmon.
Statement of relevance

This study confirms the differences in texture observed by the industry and adds to the existing knowledge regarding the proximate composition of Atlantic salmon from aquaculture. Moreover, it shows that analysing different quality parameters holistically may uncover a new dimension in the information regarding differences between companies and regions of Norway in relation to the final quality of the salmon.