Fatty acids in the roe lipids of common food fishes

Fatty-acid Profiles and Fingerprints of Seven Types of Fish Roes as Determined by Chemometric Methods

The fatty acids in seven species of fish roes were determined by GC-MS in combination with principal component and cluster analyses in order to derive their fatty-acid profiles and fingerprints. Twenty-three common chromatography peaks were identified in the fatty-acid fingerprints of the seven fish roes. A total of 19 typical fatty acids were identified in the fish roes studied. The fatty acid contents of the roes were significantly different, with saturated-fatty-acid contents in the seven roes ranging from 26.69% to 41.81%, and the unsaturated-fatty-acid contents ranging from 57.65% to 72.21%, the total EPA and DHA content (37.20%) is high in E. cypselurus roe, especially. The seven roe species were clearly distinguished according to fatty-acid composition and content by principal component analysis (PCA) and divided into two groups by cluster analysis (CA). PCA of the fatty acid data yielded three significant PCs , which together account for 94% of the total variance; with PC1 contributing 54% of the total.

Chemical composition of Greek avgotaracho prepared from mullet (Mugil cephalus): nutritional and health benefits

Crude composition, lipid composition, and tocopherols, ascorbic acid, cholesterol, phytosterols, and squalene content together with fatty acids and antiplatelet activities of total, neutral, and polar lipids of avgotaracho (wax-covered, dried, and salted Mugil cephalus roe) were studied and compared with those of similar products. Wax and steryl esters accounted for 63.7% of roe lipids followed by phosphatidylcholine (PC), which comprised 20.3%. Wax esters were rich in saturated fatty alcohols, monounsaturated fatty acids, and long chain omega3 highly unsaturated fatty acids (HUFA). The fatty acid distribution in roe total and neutral lipids was similar to that of wax esters, while in polar lipids, the omega3 HUFA predominated. Avgotaracho provides significant amounts of protein, fat, alpha-tocopherol, ascorbic acid, and PC, certain amounts of squalene and phytosterols, and cholesterol at levels comparable to hens' eggs. Total, polar, and neutral lipids of avgotaracho exhibited a strong inhibition of platelet activating factors and thrombin, with polar lipids being more active. The results obtained indicate that avgotaracho is a food of high nutritive value, rich in protein and lipids with a healthy lipid profile in terms of omega3/omega6 ratio and major fatty acid classes, while the antiplatelet activity of its oil indicates a putative antithrombotic potential.

Comparison of fatty acid profiles of spawning and non-spawning Pacific herring, Clupea harengus pallasi

Crude lipid and fatty acid composition from liver, intestine, roe, milt and flesh of spawning and non-spawning Pacific herring (Clupea harengus pallasi) were examined to determine the relative effects of spawning on the nutritional value of herring. Depletion of lipid due to spawning condition was significant (P<0.01) in all organ tissues and flesh of spawning herring. The lipid content ranged from an average of 1.9 to 3.4% (wet weight basis) in different organ tissues of spawning herring, to 10.5 to 16% in non-spawning fish. The fatty acid profile exhibited many differences in the relative distribution of individual fatty acids among organ tissues and between the two fish groups. Oleic acid (C18:1n-9), a major monounsaturated fatty acid (MUFA) found in all tissue lipids, decreased significantly (P<0.01) in spawning fish. The two monoenes, C20:1n-9 and C22:1n-11, occurred at high concentrations in the flesh but at only minor proportion in the digestive organs and gonads. Spawning herring also had significantly (P<0.01) higher polyunsaturated fatty acids (PUFA) content in the organ tissues, particularly in the milt and ovary, with docosahexaenoic acid (C22:6n-3, DHA) having the greatest proportion. Among the n-6 fatty acids, only C18:2n-6 and C20:4n-6 occurred at notable amounts and were present in higher proportions in spawning fish. We concluded that although relatively higher n-3 fatty acid content was found in the organ lipids of spawning herring, they are not an energy-dense prey food source due to the fact that both flesh and gonads contain a very low amount of lipid.