Effect of freezing on the chemical quality changes and fatty acid composition of cultured shrimp muscle, Litopenaus vannamei

Abstract

Effect of freezing on the chemical quality and fatty acid composition of cultured shrimp muscle, Litopenaus vannamei were investigated by measuring moisture content, ash, total protein content, total lipid content, fatty acid composition, and Thio barbituric Acid (TBA) during 6 month keeping in frozen storage at 18°C. According to the results, moisture content (75.93% to 73.10%), ash (1.5% to 2.07%), total protein content (25.3% to 20.87%) and total lipid content (0.83% to 0.23%) changed during six month of frozen storage. PUFA (45.21%) content was higher than the SFA (30.08%) and MUFA (19.32%) content. The poly chain unsaturated fatty acids, saturated fatty acids and mono chain unsaturated fatty acids in shrimp muscle were C18:2n6 (15.32%), C20:5n3 (9.68%), C22:6n3 (8.48%), C16:0(15.18%), C18:0 (13.04%) and C18:1n9 (15.32%), respectively. The thio barbituric acid values (TBA) ranged from 0.0065 to 0.35 mg malonaldehyde/kg during freezing storage. The lipid stability of shrimp muscle, were in acceptable limit during frozen storage for up to 6 month.