SEASONAL VARIATIONS OF TOTAL LIPID AND FATTY ACID CONTENTS IN THE MUSCLE OF TWO AUSTRALIAN FARMED ABALONE SPECIES

Abstract

ABSTRACT The total lipid content and individual fatty acid (FA) concentrations of two farmed abalone species, greenlip abalone (Haliotis laevigata) and blacklip abalone (Haliotis rubra), were analyzed through four seasons using gas liquid chromatography. Similar variations were recorded for the two species. Significantly higher concentrations of total lipid and total saturated fatty acids were found in summer, while the contents of total n‐3 and n‐6 polyunsaturated fatty acids (PUFAs) and total monounsaturated fatty acids were markedly higher in winter and spring. The two predominant n‐3 PUFAs were eicosapentaenoic acid (EPA, 20:5n‐3; 34–43%) and docosapentaenoic acid (DPA, 22:5n‐3; 40–53%). The seasonal variation of EPA was similar to that of total n‐3 PUFA, while the contents of DPA were significantly higher in winter, spring and summer than in autumn. A higher n‐3/n‐6 PUFA ratio was found in winter and autumn in greenlip abalone. Other main FAs, including 16:0, 18:0, 17:1, 18:1n‐9, 18:1n‐7, 18:2n‐6, 20:4n‐6 and 22:2 NMI, also showed seasonal variations. Farmed abalone represents a source of the health‐benefiting long‐chain n‐3 PUFA (n‐3 LC‐PUFA) for human consumption, with n‐3 LC‐PUFA content of 65–106 mg/100 g.