This study evaluated the fatty acid composition and the nutritional profile of Brycon cephalus and Brycon microlepis, fish species from the central Amazon basin, by different methods of quantification. The methods applied were: area normalization (MAN), internal standard (MIS), alternative theoretical (MAT) and alternative experimental (MAE). Significant differences were observed between the methods applied and the species studied. MAN supplied poor information about fatty acids composition and diet formulation, presenting only fatty acid profiles. MIS, MAT and MAE supplied fatty acids composition information on a mass basis. MAT and MAE overestimated results, whereas MIS presented the most accurate results. B. cephalus and B. microlepis showed high contents of approximately 65 mg g-1 of n-3 fatty acids. Eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) content totaled, 104.37 mg 100 g-1 and 117.89 mg 100 g-1 for B. cephalus and B. microlepis, respectively. The nutritional profile of both fish species showed favorable indices for nutritional quality of the lipid fraction, indicating that both Brycon species are healthy dietary choices.
Keywords: Amazon basin; DHA; EPA; Freshwater fish; Nutritional quality index.