Muscle fibre density in relation to the colour and texture of smoked Atlantic salmon (Salmo salar L.)

Muscle fibre cellularity was quantified during seawater growth in populations of predominantly early (strain X) and late maturing (strain Y) Atlantic salmon (Salmo salar L.). The fibre density (number mm(-2) white muscle cross-sectional area) in the fresh fillet was related to pigment concentration, colour as determined with the Roche SalmoFan(TM), and lipid content. The relationship between fibre density and the textural characteristics of the smoked fillet, as assessed by trained taste panels, was also determined. There was no significant correlation between astaxanthin concentration and muscle fibre density. However, significant positive relationships were obtained between Roche SalmoFan(TM) score and fibre density, explaining 33% and 44% of the total variation in colour visualisation in strains X and Y, respectively. Significant positive correlations were observed between muscle fibre density and all four measures of texture assessed by the taste panels, "chewiness", "firmness", "mouth-feel" and "dryness", A firm texture was therefore associated with a high muscle fibre density. At harvest, the lipid content of the fillet was significantly higher in strain X (11.2%) than strain Y (7.0%). There was, however, no significant correlation found between sensoric "oiliness" score and the percentage lipid content of the fillet. The results indicate that muscle fibre cellularity is an important factor in several key flesh quality traits. The potential for manipulating muscle cellularity to produce desirable flesh quality characteristics is briefly discussed. (C) 2000 Elsevier Science B.V. All rights reserved.