Perfil de ácidos graxos de espécies de de pescado de água-doce nativas da Região Sul do Rio Grande do Sul e Uruguai.

Abstract

Fish has been recognized by its high nutritional value of its lipids, especially by the content in polyunsaturated fatty acids, which perform several functions in the human body, including the protecting effect to the developing of cardiovascular diseases and rheumatoid arthritis. As a result of this, some species have been investigated as potential sources of polyunsaturated fatty acid, mainly omega-3 (PUFA's n-3). Sea fish are well- known sources of these fatty acids, however, it is lacking information about freshwater species. In Rio Grande do Sul, the low consumption of fish has also been associated to lack of information about the species, such as, composition and fatty acids profile, conservation and stability of nutraceutical properties. Freshwater species such as Traíra (Hoplias malabaricus), Jundiá (Rhamdia quelem) and Pintadinho (without taxonomic classification) can be found in Southern of Rio Grande do Sul and also Uruguay. The aim of this study was to investigate the fatty acids profile of the Traíra and Jundiá, apart from evaluating the stability of the slices and fillet of the Traíras and Jundiás under freezing. Right after capture, the fish were cleaned, eviscerated, transformed in slices and fillets, and stored under freezing ( -18°C/8 meses) and submitted to analysis of proximal composition, pH, acidity, thiobarbituric acid, peroxide value and fatty acids profiles. Slices and fillets of the Traíra (Hoplias), as well as fillets of Jundiá (Rhamdia quelen) have shown reduction in the acidity values after 4 months of storage, however, in Jundiá (Rhamdia quelen) slices it has been observed a reduction right after the second month of storage. According to the data of peroxide value and the values of thiobarbituric acid, it is observed that after the second month the samples have shown themselves in the pick of the oxidation process, except from the slices of Jundiá (Rhamdia quelen). Traíras cuts are sources of PUFA's. Traíras Cuts are excellent sources of the MUFA's.