Quality attributes and properties of surubim (Pseudoplatystoma spp.) meat

Abstract

The aim of this study was to evaluate the quality attributes and properties of fillets from surubins (Pseudoplatystoma spp.) reared in cages and fishponds. The design of the study was completely randomized, with two treatments (cage and fishpond) and 16 replicates each. The fillets from fishes reared in cage and fishpond had a mean total weight of 134.71 ± 33.11 g and 151.56 ± 18.56 g, respectively. The following parameters were analyzed: pH, water retention capacity (WRC), color (L* brightness), (a* red), (b* yellow), and shear force (SF). The data were subjected to analysis of variance and the means were compared by Tukey’s and Mann-Whitney (nonparametric) tests. Statistically significant differences (p<0.05) were observed for WRC, SF, and pH variables. Only for color attributes (L*), (a*), (b*), no statistically significant difference (p>0.05) was detected between the treatments. A lower pH (6.17 ± 0.23) was observed in fillets from surubins reared in cage. As this is close to the isoelectric point of myofibrillar proteins, it reduces their net charge and, consequently, their capacity to retain water. Lower WRC of fillets obtained from fishes reared in cage (61.46 ± 1.62%) implies loss of nutritional value through the exudate released which results in drier fillets and compromised tenderness. In fillets from cage production, SF (1.06 ± 0.22 kgf) was higher than those from fishpond, i.e., the higher the shear force, the lower the tenderness of the fillet. On the basis of the observation that fillets from fishes reared in fishponds were more tender, this study confirmed that the quality of surubin fillets is influenced by the production system.