Fontes de contaminação por Staphylococcus aureus na linha de processamento de queijo prato Identification of main sources of contamination with Staphylococcus aureus in Prato cheese manufacturing process

Com o objetivo de identificar as principais fontes de contaminação por Staphylococcus aureus e Staphylococcus produtores de coagulase (SC+), avaliou-se o processo de fabricação de queijo prato em um laticínio de Lavras, MG, durante os meses de outubro de 2000 a abril de 2001. As análises microbiológicas foram feitas no leite cru, no leite pasteurizado resfriado, nas mãos e antebraços dos funcionários, na salmoura, na água de imersão das fôrmas e no queijo embalado. Contagens elevadas de SC+ e de S. aureus (4x10³ a 4,8x10(6) UFC/ml e 4x10³ a 3,3x10(5) UFC/ml, respectivamente) foram encontradas em quatro avaliações no leite cru. Após a pasteurização, as contagens foram reduzidas a In order to identify the main sources of contamination with Staphylococcus aureus and Staphylococcus coagulase positive (SC+), a manufacture process of prato cheese in a plant located in Lavras, State of Minas Gerais, was evaluated five times from October/2000 to April/2001. Raw and pasteurized milk, hand and forearms of cheese makers, brine, hoops flushing water and cheeses were analyzed for SC+ and S. aureus. High counts of SC+ and S. aureus (4x10³ to 4.8x10(6) CFU/ml and 4x10³ to 3.3x10(5) CFU/ml, respectively) were found in raw milk in four evaluations, but they decreased to values lower than 1 CFU/ml after pasteurization. In three evaluations, counts of SC+ in prato cheese samples were above legal limits (10(4), 10(5) and 2.3x10(5) CFU/g). The hoops flushing water and brine were not important contamination sources, both with counts lower than 1CFU/ml. The cheese makers probably were the main source of contamination, since high counts in cheese were correlated to high counts in their hands (4x10² CFU/cm²) or forearms (4.7x10² and 3.3x10³ CFU/cm²)