Textural properties of raw Atlantic salmon (Salmo salar) fillets measuredby different methods in comparison to expressible moisture

摘要

Textural properties of fresh Atlantic salmon (Salmo salar) fillets were measured on seven locations along the fillet by four different instrumental methods, and were correlated to expressible moisture. Two methods were based on puncturing, either by using a flat ended cylinder, measuring hardness at different distances into the fillet and the first fracture (yield point) of the muscle fibres, or by a non-destructive method using a spherical probe to measure the hardness of the fillet. The other two methods were based on Kramer shear-compression cell or Warner-Bratzler shear cell, by shearing the fillet with blades, measuring the shear force (toughness). The ability to separate textural properties in different muscle segments by using these four methods were compared. The expressible moisture, was determined by using the filter paper method by compression. Hardness and shear force of the fillets generally increased from the anterior to the posterior part of the fillet while the necessary force applied to map the yield point decreased towards the tail section. The results from the present study indicated that the puncture method with the spherical probe and the shearing device by Warner-Bratzler were better suited for measuring differences in the textural properties between different parts of raw salmon fillet, than the flat ended cylinder and Kramer shear compression cell. The expressible moisture, varying between 1.8 and 2.7%, showed a significant (P < 0.05) linear correlation with the spherical probe texture measurements (r = 0.83) and the Kramer shear compression cell (r = 0.77).