Microstructure and texture of fresh and smoked Atlantic salmon, Salmo salar L., fillets from fish reared and slaughtered under different conditions

This study was carried out to examine differences in microstructure and tex ture of fresh and smoked farmed Atlantic salmon Salmo salar L. fillets with different biological characteristics. The left fillet was analysed fresh a nd compared with the salted and smoked right fillet from each individual fi sh. Light microscopy and image analysing techniques were used to study both transversal and longitudinal sections of the muscle. The fish muscle fibre s shrank during the salting and smoking process, but sarcomere length did n ot change. After smoking, a considerable number of fat globules were disper sed among the muscle fibres. The biological characteristics studied were ba sed upon diploid and triploid fish held in both sea cages and land-based ta nks. Different starvation times were used and one group was stressed during slaughter. The cross-sectional area of muscle fibres from triploid fish wa s found to be larger than from diploid fish, both in fresh and smoked fille ts.