Quality characteristics of sharpsnout sea bream (Diplodus puntazzo) from different intensive rearing systems

摘要

An experimental investigation was carried out on sharpsnout sea bream (Diplodus puntazzo) reared in cage and in tank to evaluate the influence of the different cu1turing conditions on the nutritional quality of the fish. Fillets from fish of the same genetic origin and size, reared separately in tank and in cage, were analysed for proximate composition, inorganic elements, unsaponifiable lipid fraction compounds. fatty acid profiles of total, neutral and polar lipids and for textural properties. The proximate composition of differently-reared fish did not differ significantly except for the greater lipid content of the tank-reared specimens. High performance liquid chromatography of unsaponifiable lipids showed significantly higher levels of squalene, cholesterol and all-trans retinol in tank-reared fish fillets. Gas chromatography of total, neutral and polar lipids showed few differences between the fatty acid profiles of tank- and cage-reared fish. Firmness and amount of expressed liquid were also influenced by the rearing techniques.