Tambaqui (Colossoma macropomum) sous vide: characterization and quality parameters

The objective of this study was to evaluate the microbiological, physical and physico-chemical quality parameters of sous vide preparation of pen-reared tambaqui (Colossoma macropomum). To prepare the tambaqui sous vide, 200 g of fillet, 50 g of basil sauce (1:4 fish fillet: sauce ratio) and 10 mL of 5% sodium lactate were used. The product was then vacuum-packaged, pasteurized at 65 degrees C for 12.5 min and refrigerated. The presence of Salmonella spp., sulfite-reducing Clostridium and Listeria monocytogenes was not detected in the samples analyzed. The coliform count at 45 degrees C and coagulase-positive staphylococci were below the limit (10(3)) permitted by the law in vigor. Water retention capacity and chloride content analyses revealed that the tambaqui fillet differed significantly (P<0.05) from the sous vide because of the addition of basil sauce. The total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARS) content of the fillet and sous vide were below the limits established by the law, indicating good quality. The lightness (L*) and yellow color (b*) of the fillet and the sous vide did not differ significantly (P>0.05), but the red color (a*) decreased in the sous vide, which is related to the addition of basil sauce. The chroma (C*) and hue angle (h degrees) differed significantly (P<0.05), and the fillet samples were lighter in color, whereas the sous vide was characterized by yellow color. The n-6/n-3 ratios found for the fillet and the sous vide are within the recommended values, which is important for human metabolism. The fillet and sous vide also had high calcium, zinc, magnesium and potassium concentrations. It is concluded that tambaqui sous vide is a good source of nutrients, rich in fatty acids and minerals essential for human health.