Avaliação de pontos de contaminação dos ambientes de produção do Queijo Canastra por estafilococos coagulase-negativos

This study evaluated the occurrence of Coagulase-Negative Staphylococci (ECN) in different microenvironments involved in the production of Minas Artesanal Canastra Cheese (QMAC), with the aim of identifying potential critical contamination points. Sampling was carried out on four properties regulated by the Minas Gerais Institute of Agriculture (IMA), encompassing 29 collection points distributed among milking parlors, cheese factories, utensils, handlers' epithelia, raw materials, and products at different stages. Collections occurred in two climatic seasons, resulting in 16 observations per sampling point. Presumptive identification of staphylococci involved plating on Baird-Parker medium, purification on nutrient agar, and application of catalase, Gram staining, and slow coagulase tests. The results showed no statistically significant difference between the dry and rainy seasons at any of the 29 points analyzed. High frequencies of ECN were found in human and animal epithelia, contact surfaces, and cheeses aged 3 and 14 days, indicating that these locations constitute persistent reservoirs. The water used in processing showed a total absence of ECN, reflecting sanitary adequacy. The variability observed between individual milk samples showed that contamination is not homogeneous among animals. The data suggest that the origin of ECN is associated both with direct contact with handlers and animals and with possible environmental persistence on structural surfaces and utensils, possibly related to biofilm formation. It is concluded that ECN are widely distributed throughout the production chain of artisanal Minas cheese and that their consistent presence at critical points highlights the importance of continuous hygienic-sanitary monitoring, the maintenance of good manufacturing practices, and the review of structures and workflows on the evaluated properties. The findings contribute to the understanding of the microbial ecology of artisanal Minas cheese and offer support for control strategies that ensure the quality and safety of the artisanal product.