Diagnosis of the microbiological quality of fiscal artisanal Minas cheese samples

Abstract

Minas Gerais State is the largest producer of artisanal cheeses in Brazil. In order to preserve production traditions and guarantee sanitary quality, the laws, decrees and other regulations have been constantly updated. Considering its inspection duties and aiming to identify compliance with the microbiological requirements defined in the legislation, the Instituto Mineiro de Agropecuária (IMA) took 1390 indicative samples of Artisanal Minas Cheese (AMC) from 364 cheese dairies in the micro-regions of Araxá, Campo das Vertentes, Canastra, Cerrado, Serra do Salitre, Serro and the Triângulo Mineiro. Coliforms at 35 °C, Escherichia coli, coagulase-positive staphylococci, Salmonella spp. and Listeria monocytogenes were analyzed at the Laboratory of Microbiological Safety in Food at IMA, according to the analytical methodologies determined by the Brazilian Ministry of Agriculture, Livestock and Supply. The mean coliform count at 35 °C, E. coli and coagulase-positive staphylococci ranged from 1.0 to 5.3 log CFU/g, 0.3 to 3.3 log CFU/g and 1.0 to 6.3 log CFU/g, respectively. Thus, 18.7%, 14.1% and 25.0% of the samples, respectively, did not conform with the legislation for these microbial groups. In addition, Salmonella spp. was present in one sample and L. monocytogenes in seven samples. The percentage of non-compliance per micro-region analyzed was 30% in Araxá, 29% in Campo das Vertentes, 23% in Canastra, 44% in Cerrado, 32.5% in Serra do Salitre, 50% in Serro and 20% in the Triângulo Mineiro. Of the cheeses sampled before completing the minimum period of ripening required by state legislation, 51.5% were non-compliant, while for those that completed the minimum time, this index was 24.2%, evidence that the ripening time is essential for the adequacy of AMC to the microbiological standards. On the other hand, the percentages of non-compliance showed very similar values (39.3% and 42.0% respectively) in the dry and rainy seasons. When evaluating the evolution of microbiological quality over 11 years, and comparing the micro-regions, no tendency for improvement in quality was found, and of the hygiene indicator microorganisms, coagulase-positive staphylococci were responsible for the highest number of nonconformities, especially in the Serro regions. Thus, there is a need to implement projects and public policies to improve the microbiological quality of the AMC.