Occurrence of filamentous fungi isolated from matured blue cheese

Abstract

Matured blue cheese can be made from cow's milk associated with the inoculated fungus Penicillium roqueforti, which guarantees specific sensorial characteristics. Recently, Brazil's fine cheese production and consumption have increased by more than 200%, highlighting the relevance of microbiological quality control of these products. Fungal contaminations are responsible for significant losses in cheese production and provide a suitable environment for mycotoxins production, constituting a hazard to public health. In this work, we evaluated the mycological contamination profile of matured blue cheeses commercialized in Brazil. Samples of ten different brands were analyzed by serial dilution method, by plating in the Dicloran Rose of Bengal Chloramphenicol (DRBC) culture medium and Dicloran Glycerol Medium Base (DG18). Subsequently, different fungi morphotypes were isolated and morphologically identified. As a result, 461 fungi were isolated and identified, notably Aspergillus aculeatus, Penicillium roqueforti and Penicillium solitum. All samples were contaminated by filamentous fungi, amongst those, many already reported as mycotoxin producers, which underlines the relevance of microbiological monitoring. ResumoO queijo azul maturado pode ser fabricado a partir do leite de vaca, associado à inoculação do fungo Penicillium roqueforti, o qual confere características sensoriais específicas. Recentemente, a produção e o consumo de queijos finos no Brasil aumentaram mais de 200%, destacando a relevância do controle de qualidade microbiológica desses produtos. Contaminações fúngicas são responsáveis por perdas significativas na produção de queijos e provêm um ambiente propício para a produção de micotoxinas, constituindo-se um risco à saúde pública. Neste trabalho, avaliamos o perfil de contaminação micológica de queijos azuis maturados comercializados no Brasil. Amostras de Occurrence of filamentous fungi isolated from matured blue cheese Ribeiro, E. S. S. et al. Braz. J. Food Technol., Campinas, v. 23, e2019074, 2020 | https://doi.org/10.1590/1981-6723.07419 2/8 dez diferentes marcas foram analisadas pelo método de diluição seriada, através de plaqueamento em meio de cultura Ágar Dicloran Rosa de Bengala Cloranfenicol (DRBC) e Ágar Dicloran Glicerol Médium Base (DG18). Subsequentemente, diferentes morfotipos fúngicos foram isolados e morfologicamente identificados. Como resultados, 461 fungos foram isolados e identificados, notavelmente, Aspergillus aculeatus, Penicillium roqueforti e Penicillium solitum. Todas as amostras analisadas apresentaram contaminação por fungos filamentosos, muitos dos quais já reportados como produtores de micotoxinas, enfatizando a relevância do monitoramento microbiológico.

Physicochemical characterization, fatty acids profile and lipid quality of Gorgonzola cheeses

“…In Brazil, Gorgonzola cheeses are produced from cow's milk, with the addition of Penicillium roqueforti fungus and matured for a minimum of 90 days. This cheese has a pungent aroma and flavor, an open texture, and a soft, smooth and crumbly consistency (Ribeiro et al, 2020). This type of cheese has gained popularity and has seen significant growth in the Brazilian market.…”