Biochemical and Bacteriological properties of fresh and frozen sold cephalopods in the Egyptian market.

Abstract

arious cephalopods are available for seafood consumers in the Suez Canal area either caught from the Suez Canal and stored in ice during transporting and marketing or imported and sold frozen in retail market. The lower price of imported cephalopods compared with the fresh ones makes it more demanded by consumers, restaurants and hotels. The objective of this study is to evaluate the quality and safety of fresh/chilled squid (Uroteuthis duvauceli) and cuttlefish (Sepia pharaonis) compared to frozen imported squid in the Egyptian market through chemical, biochemical and bacteriological analyses. The chemical analysis revealed that the mantle tissue pH, volatile base nitrogen (VBN) and trimethylamine (TMA) in frozen squid were significantly higher (P < 0.05) than that in fresh/chilled samples. The biochemical analysis showed that the crude protein content (% dry weight) was significantly lower (P < 0.05) (14.2±0.73%) in frozen samples than that in fresh squid and cuttlefish (17.25±0.41% & 19.95±0.55% respectively). The total lipid content was generally low, ranging from 0.39 – 1.77% in all samples. Most of saturated fatty acid content of the three samples was presented as C16:0, monounsaturated fatty acid content as C18:1 and polyunsaturated fatty acid (PUFA) content as eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic (DHA, C22:6n-3). EPA and DHA contents were significantly lower (P < 0.05) in frozen squid than in fresh samples. The major essential amino acids (EAA) in the three samples were lysine, arginine, and leucine. The major non-essential amino acids (NEAA) were glutamic acid, aspartic acid and glycine. EAA and NEAA values were significantly lower (P < 0.05) in frozen squid than in fresh cuttlefish. Bacteriological results suggest that hydrogen sulphide producing bacteria constituted a significant proportion of the total spoilage flora in frozen samples, while Pseudomonas sp. constituted a major part of the spoilage flora of fresh samples. An overall look into the data obtained showed that there might be significant health hazards to humans from consuming imported frozen squid besides its much lower nutritional value than fresh samples.