Chemical composition of European squid and effects of different frozen storage temperatures on oxidative stability and fatty acid composition

The chemical composition of European squid (Loligo vulgaris) mantles and tentacles and the lipid oxidation during frozen storage at three different temperatures (−20º, −40º and −80 °C) were investigated. The moisture, fat, protein and ash contents of tentacles were 80.72%, 1.44%, 16.16% and 1.63% while the same contents for mantle were 78.54%, 1.37%, 18.52% and 1.45% respectively. The initial free fatty acidity (FFA), peroxide (PV) and thiobarbituric acid reactive substances (TBARS) values of tentacles were 1.17%, 1.80 meq O2/kg fat and 0.80 mg malonaldehyde/kg respectively. The same results for mantles were 1.38%, 2.20 meq O2/kg fat and 0.73 mg malonaldehyde/kg respectively. PV and TBARS values increased with the storage time for all samples and higher storage temperature resulted with higher PV and TBARS values. The initial fatty acid compositions of L. vulgaris mantles were 29.95% saturated (SFAs), 9.95% monounsaturated (MUFAs) and 59.31% polyunsaturated fatty acids (PUFAs) and tentacles were 34.16% SFAs, 10.69% MUFAs and 55.15 PUFAs. SFAs content were increased but MUFAs and PUFAs contents were decreased during frozen storage of mantles and tentacles.