Effects of freezing storage on the biochemical composition in muscles of Saurida undosquamis (Richardson, 1848) comparing with imported frozen

Abstract

The present study was carried out to determined the quality changes of the nutritive value (protein, lipid, moisture, ash, pH) and minerals of fresh Saurida undosquamis and to examine the effect of freezing for (7, 14, 21) days respectively at (-20 °C) comparing with imported frozen fish. The chemical analysis of fresh muscles recorded high values of protein %, lipid % and moisture while there was a significant (P<0.05) decrease after 21 days of both freezing and imported frozen fish. The total lipid content of all groups of samples remained more or less stable during 21 days of frozen storage and no significant change was noted during freezing. The ash content was slight increase of no significant importance. pH values increases with duration of storage. The maximum values of Mg, Ca and P recorded (1.16±0.03, 9.28±0.50 and 3.28±0.41) for fresh samples and decreased with freezing times. A significant difference was observed between fresh fish, freezing samples after 7, 12 days and imported frozen fish for calcium and phosphorus concentration. In conclusion, the freezing of fish influenced the biochemical composition and mineral contents of their muscles also the quality of fish samples during storage revealed the decreasing of the taste with increasing duration of storage.