Quality of fresh native fish in supermarkets in Cuiabá, Mato Grosso, Brazil

The objective of this study was to evaluate the quality of native fresh fish sold in the main supermarket chains in the city of Cuiabá, Mato Grosso. Five commercial establishments were sampled by collecting six fish from each, totaling 30 fish, which were evaluated for their sensory, physicochemical, and microbiological properties. The temperature of the samples at the commercial establishment varied between 0.7°C and 7.9°C, reaching inadequate storage values. Sensorially, intermediate quality characteristics were observed. The physicochemical parameters were expressed according to the Brazilian legislation, with pH values ranging from 6.17 to 6.43 and total volatile basic nitrogen values ranging from 5.85 to 14.62 mgN∙100g−1. However, there were counts of up to 1.7 × 107 CFU∙mL−1 for the coagulase-positive Staphylococci, and >1.1 × 103 NPM∙mL−1 for coliforms at 45°C, which are both higher than the limits tolerated by the current Brazilian legislation and literature. It was concluded that the physicochemical, sensory, and microbiological analyses presented contradictory results, because of the presence of pathogenic microorganisms. Thus, the guarantee of the quality and safety of fish should be the responsibility of commercial establishments, as the consumer does not have adequate tools for this at the time of purchase.