Caracterização físico-química e microbiológica de tambaqui (colossoma macropomum) cultivado em tanque-rede

Abstract

The state of Tocantins has great potential for the development of the fish chain, due to its favorable environmental conditions. Among the fish with high potential for breeding in the state is Tambaqui, because of this and its affordable price it can become a common protein in the diet of Brazilians. In this context, this study aimed to evaluate the microbiological and physicochemical parameters of the tambaqui species (Colossoma macroporum) fish, cultivated in a net tank in the damming of the Tocantins River in the municipality of PalmasTo. The use of colorimetry was also proposed to obtain objective data from subjective sensory perceptions, building a relationship between freshness and color change in the fish cornea during storage time. The presence of coagulase-positive staphylococci was identified in the musculature after the 20th day and in the surface swab in quantities greater than those accepted by health standards). Salmonella spp. and coliforms at 45ºC (>1.1x103 NMP/g) in musculature samples, Tambaqui surface swab and in water from cages. No typical colonies of Escherichia coli were identified in the musculature of any analyzed specimen; however, they were present in water and surface swab. The total mesophilic aerobic bacteria count showed no correlation of deterioration with storage time, however psychrotrophic bacteria multiplied during the 20 days of ice storage. Muscle pH ranged from 6.80 to 7.54, and moisture ranged from 76.83% to 79.13%. There were no significant changes in the values of proteins, lipids and total color variation, but there was a decrease in minerals, detection of a reduction in brightness and an increase in green color during the storage time.