Changes in fatty acid composition in sardines (Sardinops melanosticta) with cooking and refrigerated storage

The influence of cooking and later storage in a refrigerator for 7 days on the fatty acid composition of lipids in sardines (Sardinops melanosticta) was studied. The total lipid and triacylglycerol (TG) levels did not change and the phospholipid (PL) level decreased somewhat with cooking or during storage. The fatty acid composition of the total lipids and TG fractions was little changed and that in the PL fractions was somewhat changed by the cooking. The composition of the polyunsaturated fatty acids (PUFA) in lipids of sardine precooked at 100 or 170 degrees C for 30 min changed from 42.7 to 38.3 or 33.5%, respectively, for total lipids and from 51.5 to 38.4 or 37.6%, respectively, for PL fractions during storage. The fatty acids in lipids from the ordinary meat of sardine was stable and those in the dark meat were extremely unstable during storage after cooking. We concluded that the PUFA in the lipids of sardines were stable to cooking, but unstable to oxidation during storage in a refrigerator. The PUFA of lipids in the dark meat of sardine were extremely unstable to oxidation.