Evaluation of freshness and physicochemical characteristics of blankets of pirarucu (Arapaima gigas) bred in captivity at different ages in relation to the seasons

This study aimed to evaluate the freshness and physicochemical characterization of pirarucu blankets at different ages bred in captivity in excavated tanks in northern Mato Grosso State, Brazil, in different seasons (rain and dry seasons). Four harvests were performed in two different tanks and five specimens obtained in each evaluated period, with animals aged 18 and 24 months, respectively, at the beginning of the experiment. The animals were slaughtered in a local establishment that had an inspection service following humane standards, and the blankets were later sent to analysis. The samples were analyzed for freshness via total volatile nitrogenous bases and physicochemical characteristics (pH in 24 h, water activity, water retention capacity, dripping loss, cooking loss, and shear force). There was a statistical difference for total nitrogenous volatile bases and shear force with higher values in the rainy season (24 month-of-old animals). Additionally, pH and water activity differed statistically at 24 h in the same period, albeit for 18-month-of-old animals. It was possible to conclude that climate variation affected the freshness and physicochemical characteristics of the pirarucu blankets while age did not.