Effects of filleting method, stress, storage and season on the quality of farmed Atlantic cod (Gadus morhua L.)

Summary

The effects of filleting method, pre-slaughter stress, storage and season on drip loss, water content, water-holding capacity, rigour contraction and colour in Atlantic cod, Gadus morhua L., were examined. A total of 182 fish were sampled under commercial conditions. To test the effects of filleting method and stress, stressed (S) and unstressed (C) fish were filleted either pre (Pr) or post rigour (Po) at 1 and 48 h post mortem, receptively. The muscle pH significantly decreased from 0 to 144 h of storage in all groups. The onset of the rigour contraction was more pronounced in the Pr-S group as compared with the Pr-C group, but after 144 h of storage, no difference in degree of contraction was observed. Filleting method, stress and storage time influenced the colour of the fillets. Post-rigour filleting caused a significantly increased in measured Lightness (L*) during storage. Stress caused a significant increase in measured redness (a*). No significant difference was found for water-holding capacity. The water content was influenced by filleting method, where the Pr-S group had a significantly lower water content compared with the Pr-C groups; water content changed also according to season. The findings of this study show that stress, filleting method, time of storage and season had a significant effect on the drip loss, where a combination of all factors will determine the total loss.