Title: Effect of different bleeding conditions on the colour tone of fresh, frozen and salted fillets of Atlantic cod (Gadus morhua)

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bleeding; colour; heme iron; whiteness; Atlantic cod.


Effects of different bleeding treatments on the colour of fresh, frozen and salted cod fillets were examined. Three bleeding methods were used for the fresh fillets i.e. bleeding, gutting and washing immediately after capture (A), bleeding, gutting and cleaning a whole day after capture (B) and bleeding upon capture, but gutting and cleaning the day after (C). The fish that was bled, gutted and cleaned immediately after capture was significantly whiter than fish in the other two groups. Despite not being as white as group A, group C turned out to be whither than group B. Seven different bleeding treatments were used for the frozen and salted fillets, where experiments were done with variable time, temperature and water-throughput in the bleeding tank. Results from the frozen fillets showed that bleeding the fish for 15 minutes in seawater returned the whitest fillets, but by increasing water-throughput or not allowing the fish to bleed in a bleeding tank at all returned the darkest fillets. The salted fillets however did not return the same results as fish that was only allowed a short time in the bleeding tank yielded the whitest fillets and fish that was bled in a bleeding tank with increased water-throughput yielded the darkest fillets. The results from the experiment are therefore inconclusive, as different processing methods return different results.

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