Kinetics of lipid oxidation and off-odor formation in silver carp mince: The effect of lipoxygenase and hemoglobin

The effect of lipoxygenase (LOX) and hemoglobin on the kinetics of lipid oxidation and off-odor formation was compared, using a model system of silver carp ( Hypophthalmichthys molitrix) mince. The major LOX in silver carp muscle was the 12-isozyme. Compared to hemoglobin, the LOX caused faster lipid oxidation in the initial phase but had lower lipid hydroperoxides value (POV) and less thiobarbituric acid reactive substance (TBARS) in the end. The LOX was affiliated with strong fishy odor, while hemoglobin resulted in severe oxidized oil odor. It is likely that the 2,4-heptadienal ( E, E) contributes to fishy odor, while the hexanal and nonanal are responsible for oxidated oil odor.