The Impact on the Stability of Triacylglycerols in Fish with a High Percentage of Polyunsaturated Fatty Acids Stored in a Freezer

The present work evaluated the fatty acid composition and triacylglycerol (TAG) profile of three fish species stored at -18 degrees C for 60 days through gas chromatography with flame ionization detection (GC-FID) and direct infusion electrospray ionization mass spectrometry (ESI-MS). It was found that oleic, linoleic, arachidonic, eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids were highly susceptible to lipid oxidation over a period of 60 days. Additionally, the decrease in the relative percentage of triacylglycerols (TAGs) containing unsaturated fatty acids such as EPA, DHA, and oleic acid occurred mainly when they were in the sn-3 or sn-1 positions of the TAG molecule. Therefore, it was proved that in fish meat even a low storage temperature does not prevent for the oxidation of the main unsaturated fatty acids to take place.