Flesh quality and biochemistry of light-manipulated Atlantic cod (Gadus morhua) and the significance of collagen cross-links on fillet firmness and gaping.

The aim of our study was to investigate whether light-manipulation, causing accelerated or delayed maturation, could be used as a tool to improve fillet gaping score and texture of farmed cod (Gadus morhua L.) harvested during summer. Control and accelerated groups had completed spawning by the time of harvest, and expressed sexual dimorphism in various biometric and flesh quality parameters. Pyridinoline cross-links, a key biochemical parameter investigated, were positively correlated with texture (r(2) = 0.4), as also were cathepsin B&L and sex. Gaping was also impacted by pyridinoline cross-links, together with body mass and maturation. Interestingly, the level of gaping was significantly reduced with a pyridinoline cross-link concentration of >2500 pmols g(-1) dry mass. In conclusion, light-manipulation can be used as a tool to improve flesh texture of farmed cod with a low gaping score, but with compromise of increased dress out percentage for the accelerated group.