Pesquisa de Salmonella sp., Listeria sp. e microrganismos indicadores higiênico-sanitários em queijos produzidos no estado do Rio Grande do Norte
The hygienic-sanitary quality of 24 "coalho" cheese (11 samples) and "manteiga" cheese (13 samples) samples produced in the state of Rio Grande do Norte was evaluated. All of "coalho" cheese samples presented total coliforms and 36.4% of them were positive for faecal coliforms and Escherichia coli, with values ranging from 3 to 7MPN/g. A total of 84.6% of the "manteiga" cheese samples showed total coliforms; 15.4%, faecal coliforms and 7.7%, E. coli. The population of yeasts and molds ranged from 1.9 x 104 to 4.8 x 108 CFU/g in the "coalho" cheese samples and from 1.5 x 104 to 2.8 x 108 CFU/g in the "manteiga" cheese samples. Positive coagulase staphylococci were observed in 72.7% of the "coalho" cheese samples and in 84.7% of the "manteiga" cheese samples, with counting ranging from 7.0 x 104 to 1.3 x 108 CFU/g and 2.4 x 102 to 8.6 x 106 CFU/g, respectively. Salmonella sp. was detected in 9% of the "coalho" cheese samples and in 15% of the bread cheese samples. Listeria sp. was confirmed in 9% and 15% of the "coalho" cheese and "manteiga" cheese samples, respectively. The high population of yeasts and molds observed in both kinds of cheese indicated deficiency in the hygiene and sanitation procedures becoming characterised as "product at unsatisfactory hygienic conditions". Cheeses originated from the six micro regions of the Rio Grande do Norte State involved in this study did not present food safety, mainly because of the elevated countings of positive coagulase staphylococci. The presence of Salmonella sp. and Listeria sp. characterized these cheeses as "inappropriate to the human consumption".