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Aquaculture is promising in increasing the amount of fresh Atlantic cod available all year around. The aim of this study was to investigate the effects of pre‐rigour filleting on fillet quality of wild and farmed cod. Pre‐rigour filleting resulted in significantly less fillet gaping than in fillets produced post rigour. The pre‐rigour fillets were, however, 12–13% shorter post rigour. In spite of the significantly lower water content of the muscle 6 days post mortem, a significantly higher liquid loss was seen in the pre‐rigour group. Differences in gaping score and muscle pH were dependent on whether the fish were wild or fed. Fillet gaping increased with storage time and was particularly pronounced for well‐fed cod. Fed cod had a significantly higher hydroxyproline (Hyp) content and significantly lower amount of glycosaminoglycans (GAGs) than wild cod. The ratio between GAGs and Hyp was thus significantly lower in fed cod. A connection between connective tissue components and fillet gaping may exist. However, further investigations are required.

Improved slaughtering procedures of farmed ¢sh may provide su⁄cient time so that ¢lleting can be performed pre-rigor while the muscle pH is still high. Such ¢lleting not only reduces ¢llet gaping but also lowers the transportation costs and makes fresh ¢llets available to the markets at an earlier stage. The aim of our work was to determine the weight reduction of the ¢llets due to liquid loss and to study the proteins and enzymes in the drip. After11days of cold storage, ¢llets of farmed Atlantic cod produced prerigor had a weight loss of 10% and a ¢llet contraction of 19% while for ¢llets produced post-rigor the values were 5% and 4% respectively. At the same time, approximately twice the amount of proteins had been lost from the pre-rigor-produced ¢llets. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis showed that the proteins in the drip were similar to the sarcoplasmatic proteins extracted from the muscle. Speci¢c analysis of proteolytic enzymes indicated that they are less stable in the expelled liquid than in the £esh during storage. The extensive loss of weight and proteins from pre-rigor-produced ¢llets during subsequent storage must be taken into account if such processing is considered for farmed cod.

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