Lipid quality of common carp (Cyprinus carpio) in pond culture

Sammanfattning: There is a large body of evidence that n-3 fatty acids, especially EPA and DHA are beneficial for human health. Content of these fatty acids in fish fillet can be influenced by several factors. This thesis examined differences in lipid content, lipid class and fatty acid composition among three parts of common carp fillets. The effect of genetic background on lipid content and fatty acid composition in common carp was investigated. An approach of using biologically active compound sesamin which might modulate the fish metabolism to synthesize more n-3 HUFA from ALA was tested. The results showed that lipid content and composition differed strongly among the three parts of common carp fillet. The lowest lipid content was found in dorsal white muscle (0.95±0.14%), medium in red muscle (16.7±5.0%), whereas the highest was found in abdominal wall (30.2±7.8%). Abdominal wall with the highest lipid content was dominated by triacylglycerols whereas the white muscle had the highest contribution of phospholipids. The total lipid fatty acid composition differed greatly depending on the lipid content and ratio between phospholipids and triacylglycerols. The fatty acid composition of the leanest part, the white muscle, contained a large proportion of n-3 highly unsaturated fatty acids and a ratio n-3/n-6 = 1.1, having a high proportion of phospholipids. The abdominal wall was rich in monounsaturated FA and had a lower ratio n-3/n-6 = 0.5. There were only slight differences in muscle fatty acid composition among four carp crossbreeds caused probably by differences in lipid content. Addition of sesamin did not alter muscle lipid composition in common carp.