Caracterização físico-química de filés de piava (Leporinus obtusidens) armazenados sob congelamento

Abstract

This study aimed to characterize physicochemically fillets of Piava (Leporinus obtusidens) and to evaluate their shelf-life under frozen storage. The piavas were acquired in Itaqui/RS and the analysis performed in the laboratory of Unipampa. Specimens were filleted and their fillets used for physico-chemical and shelf-life analysis. The fillets were evaluated on the day of capture (time 0) and after 30 days of frozen storage (time 1). The fillets were packed in polystyrene trays, covered with plastic wrap and stored at -18°C. At time 0, analysis were made to determinate the chemical composition of the fillets, and income. In the two times (0 and 1), analysis for pH, water activity (Aw), color, conjugated dienes, peroxides,TBARS and BVT were made. The fillets of Piava showed average yield of 47.17%. For moisture, protein, ash and lipids were obtained values of 71.29, 19.41, 1.03 and 6.06%, respectively. The pH decreased between time 0 (6.89) and time one (6.49) and Aw remained stable between the two times (0.9941 to 0 and 0.9946 time 1). BVT levels did not differ significantly (time 0 14.00 and 13.00 mg N/100g-¹ time 1), as well as the levels of peroxide (0.025 and 0.024 mEq/mg lipid). TBARS and conjugated dienes showed significant difference between time 0 and time 1 (0.004 and 0.006 nmol/mg prot.; 1.46 and 0.46 mg lipid/ml ciclohexane, respectively). The color parameters showed values for parameter L * 48.00 and 50.56; for parameter a * -0.92 and -0.73 and 7.64 and 7.52 for parameter b* for the times 0 and 1, respectively. The Piava proved to be a good source of protein and fat, with good oxidative stability, slow degradation, being a suitable specie of technological and nutritional potential.