Morfometria, rendimento de carcaça e composição do filé do beijupirá (Rachycentron canadum) cultivado em tanques-rede em mar aberto no litoral de Pernambuco

Abstract

A total of 223 specimen of cobia sampled from a culture cage sited off the coast of Pernambuco, Brazil, were randomly selected and divided into four size classes (T1 ≤ 1.0 kg; T2 = 1.01 to 2.0 kg; T3 = 2.01 to 3.0 kg; and T4 = ≥ 3.01 kg). Morphometric data were taken to estimate the length-weight relationship, condition factor (K) and the yields of carcass and fillet. The proximate composition and the profiles of amino acids and fatty acids were determined in the fillet of at least six fish from each size class. With the exception of snout length, head height and eye diameter, morphometric measurements were not significantly different between size classes. There was no significant difference in the length-weight relationship between males and females (R² = 89.86). Yields of fillet (with and without skin) and carcass increased with fish weight and were higher in T4 (43.8, 38.8 and 59.3%, respectively). The proportions of fins, viscera and skin in relation to fish weight showed no significant difference, but the proportion of head and other wastes decreased with fish size. K was also found to increase significantly with fish size. The content of protein in the fillets decreased with fish size, while moisture and lipid contents were inversely related. High levels of lysine, arginine and leucine were detected, while the most abundant fatty acids were linoleic (18:2n-6), oleic (18:1n-9) and palmitic acid (16:0), as well as EPA (20:5n-3) and DHA (22:6n-3). The present results therefore confirm the high nutritional quality of fillets from cage-cultured cobia.