Microbiota terroir do queijo Minas artesanal casca florida da região da Canastra

Abstract

Minas Gerais stands out for its cheese production in several micro-regions. At Canastra, artisanal Minas cheese has gained recognition and visibility in competitions around the world, standing out among the best in the world, attracting tourists and consumers to the producing cheese farms. The traditional way of manufacturing, the endogenous microbiota, among other factors, predict the characteristics and sensorial quality of the product. Therefore, knowing these factors is of great importance to guarantee the identity and safety of the product. The determination of the typical microbiota of the terroir, comprising filamentous fungi, bacteria and yeasts, present both on the surface and mass of the Bloomy Rind Artisanal Minas Cheese from the Canastra region was the aim of this study. To this end, cultivation-dependent and independent methods were used to evaluate samples from six different farms. Namely, amplicon sequencing of the ITS and 16S regions, identification of filamentous fungi and yeasts isolated by serial dilution in DRBC, and YEPG medium and identification of yeasts by MALDI-TOF MS. The use of different complementary methods makes it possible to profile the total microbiota and isolate the cultivable microbiota for future research. Physicochemical aspects of the samples, such as moisture, fats, proteins, pH and ash were correlated with the identified mycobiota. Investigation using an independent cultivation method showed that the most prevalent fungal species in the rind and mass were Geotrichum candidum and Diutina catenulata. Candida intermedia was more abundant only in the mass of the cheeses. Among the bacteria, the surface showed a greater diversity of genera and species, such as Lactococcus sp, Brevibacterium sp, Corynebacterium variabile and Staphylococcus sp. Only Lactococcus sp, Streptococcus salivarius and unidentified species of the genus Streptococcus prevailed in the mass of the cheeses. Differences between species prevalence stood out. In samples with greater abundance of G. candidum and Lactococcus spp., a lower prevalence of D. catenulata and C. variabile, respectively, was noted. Using cultivation-dependent methods, it was possible to isolate the species Diutina catenulata, Kluyveromyces lactis, Kodamaea ohmeri, Trichosporon coremiiforme and Geotrichum candidum both in the mass and on the surface of the analyzed cheeses. Candida intermedia, Torulaspora delbrueckii and Trichosporon japonicum were isolated only from the surface, associated with samples with higher pH values. In the mass, the yeasts Candida lucitaniae, Candida parapsilosis, Trichosporon asahii and Rhodotorula mucilaginosa were found, related to moister cheeses. G. candidum and K. lactis were related to fattier cheeses. The results contribute to the understanding of the chemical composition and microbial community of cheeses in the region and contribute to the implementation of strategies that can improve quality and safety in production. Furthermore, the preservation of the isolates enables future studies that can contribute to the knowledge of the dynamics between the microbial communities of Canastra's artisanal Minas cheese.