Influence of storage time and temperature on lipid deterioration during cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) frozen storage

Lean fish deterioration during frozen storage (-30 and -10 degrees C) for u p to 1 year was studied by the assessment of Lipid changes. Comparison betw een a formaldehyde (FA) -forming species (cod) and a non-FA-forming one (ha ddock) was carried out. Lipid damages were measured on the basis of free fa tty acids (FFA), peroxide value (PV), thiobarbituric acid index (TBA-i) and fluorescent compounds. In both species at -30 degrees C, most lipid damage indices showed significant correlations with the storage time. However, at -10 degrees C, only the FFA and fluorescence detections provided significa nt correlations with the storage time. Comparison between the fish species showed higher lipid oxidation (PV and TBA-i) and hydrolysis (FFA content) i n haddock than in cod at -10 degrees C; however, a higher fluorescence deve lopment was observed in cod at the same temperature. At -30 degrees C, litt le differences in Lipid damage indices were detected between the two specie s. (C) 1999 Society of Chemical Industry.