Composition, liquid leakage, and mechanical properties of farmed rainbow trout:: Variation between fillet sections and the impact of ice and frozen storage

Variation in quality characteristics within rainbow trout fillets, and changes in liquid leakage (LL) and mechanical properties during ice or frozen storage was studied. Fat, water, protein, and ash content, determined in frozen thawed samples, varied significantly among fillet sections. LL increased in the cranial-caudal direction, and it was highest following freezing. Dorsally, compression and puncturing resistance increased towards the tail (raw and baked), but puncture resistance of raw fillets was highest in the belly flap. The results indicated pronounced softening of the tail-half upon freezing. It is suggested that sectioning of trout fillets for different products or markets may improve utilization of intrinsic quality characteristics.