Lipid composition and fatty acid profiles of wild caught and fattened mud crab, Scylla serrata, in Sri Lanka

Abstract

There is a huge demand for mud crab (Scylla serrata) in overseas markets. The mud crabs available to the market are mainly wild caught crabs and cage fattened crabs. Crab fattening is used to fatten the thin crab or post molt crab to fill up their meat in a shorter period. In the present study, lipid levels and fatty acid profiles of wild caught and fattened mud crabs at the harvested stage as well as at the stocking and harvesting stages of the fattening process were analyzed using gas chromatography. The total lipid content of wild caught (fattened) S. serrata (0.65±0.1%) was significantly higher than that of cage fattened individuals (0.56±1%). Polyunsaturated fatty acids were the predominant group of fatty acids found in S. serrata (39%-43%) and Oleic acid (C 18:1 n-9) was the most abundant fatty acid (16%-21%). Oleic acid (C 18:1 n-9), Gondoic acid (C 20:1), Eicosapentaenoic acid (C20: 5 n-3), Docosatetraenoic acid (C22: 4 n-6) and Docosahexanoic acid (C22: 6 n-3) contents varied significantly between crabs at stocking and harvested stages of fattening process. The contents of Oleic acid (C 18:1 n-9), Gondoic acid (C 20:1) and Docosatetraenoic acid (C 22:4 n-6) were significantly different in wild caught crabs in comparison to fattened crabs. The differences in fatty acid composition among wild caught crabs (fattened stage) and cage fattened crabs (fattened stage) might be a reason for flavour difference between the two types.