No abstract

Qualidade microbiológica de carne bovina moída comercializada em supermercados do Distrito Federal, Brasil Microbiological quality of minced beef sold in supermarkets of the Federal District, Brazil

The aim of this study was to evaluate the microbiological quality of Minas fresh cheese commercialized in Federal District, Brazil. For this, 20 samples of industrialized cheeses were collected in supermarkets and 20 samples of artisanal cheeses were collected in public food markets. The analyzes performed were total count of bacteria, determination of coliforms, count of S. aureus and identification of Salmonella spp. (InvA gene) and S. aureus (SeC gene). The results showed that 26 samples (65%) were unfit for consumption according to Brazilian legislation. For industrialized cheeses, 6 samples (15%) of were unfit for consumption (3 samples for excess of thermotolerant coliforms and 3 samples for excess of S. aureus). For artisanal cheeses, all 20 samples (50%) were unfit for consumption due to the high S. aureus counts, including 6 samples that had excess thermotolerant coliforms and 1 sample that was contaminated with Salmonella. Comparing the results, industrialized cheeses showed better microbiological quality than artisanal cheeses. Thus, artisanal Minas fresh cheeses commercialized in the public food markets of the Federal District showed the presence of bacterial hazards, and there is an evident need for good hygiene practices in the entire production chain to ensure consumer food safety.

Tilapia (Oreochromis niloticus) is the most cultivated and consumed freshwater fish in Brazil. The present study aimed to evaluate the microbiological quality of ice and fresh tilapia samples commercialized in the Federal District. Tilapia samples were tested for counts of mesophilic and psychrotrophic bacteria, determination of total and thermotolerant coliforms, Staphylococcus aureus counts and presence of Salmonella. Ice samples were analyzed for determination of total coliforms and thermotolerant coliforms and presence of Escherichia coli. Of the 20 samples of fresh tilapia analyzed, ten samples (50%) presented Salmonella (genetically confirmed through the presence of the invA gene) and, therefore, were unfit for consumption. S. aureus was found in 11 samples (55%), and one sample of fillet presented S. aureus counts (3.15 CFU/g) above the limit allowed by Brazilian legislation (3 log CFU/g). S. aureus colonies were confirmed by detection of CoA gene in molecular analysis. Of the 14 ice samples analyzed, 12 samples (85.7%) were unfit for use in fish conservation due to the presence of total coliforms and 9 ice samples (64.3%) were also contaminated with thermotolerant coliforms. E. coli was isolated from 6 ice samples (42.9%) and confirmed in the molecular analysis through the amplification of the MalB gene. In conclusion, the high contamination of tilapia samples with Salmonella and of the ice used for its conservation with coliforms and E. coli indicates the need for better hygienic practices in the tilapia production chain, to increase its quality and microbiological safety.