Robiola di Roccaverano is a PDO (Protected Designation of Origin) soft cheese made with raw goat's milk, from the Piedmont region of Italy. The peculiarity of this cheese is that during the manufacturing process, a Natural Starter Culture (NSC) is added to raw milk. In this study, the viable microorganisms of technological interest, including Lactic Acid Bacteria (LAB) and fungal populations were examined in samples of raw milk, NSC, fresh and ripened cheese collected from one dairy by means of culture-dependent techniques. Firstly, the isolated colonies were analyzed by means of Random Amplify Polymorphic DNA-PCR (RAPD-PCR) and strains with similar fingerprint were clustered together. Further, representative isolates of each group were subjected to 16S rDNA or 26S rDNA sequencing. Finally, species-specific PCR was conducted to distinguish the Lactococcus lactis subspecies lactis and cremoris. Among the studied LAB, 13 RAPD-profiles were Page 2 of 32 ScholarOne support: (434) 964 4100 Journal of Dairy Science 3 obtained, corresponding to different bacterial species or subspecies. Concerning mould and yeast isolates, 5 species were found which coincided with RAPD-type. Observing the strains isolated in the study, Lactococcus lactis was the most prevalent species in raw milk and NSC samples. Instead, Leuconostoc mesenteroides was the predominant species identified in 5-and 15-days cheese isolates. Furthermore, while only these two species were detected in NSC, in raw milk and cheese Enterococcus and Lactobacillus genera were respectively found. Concerning the mould and yeast isolates, in NSC Kluyveromices spp. was mainly found, instead, in cheese samples representative species were Geotrichum candidum and Yarrowia lipolytica. Finally, the raw milk and cheese safety were evaluated and the samples complied with the standard required by the European Commission Regulation 2073/2005.

In this study, high-throughput sequencing (HTS) was used to investigate the microbiota of Robiola di Roccaverano production, an artisanal Protected Designation of Origin soft cheese made with raw goat milk by addition of a natural milk starter (NMS), from the Piedmont region of Italy. Different steps of production of Robiola di Roccaverano cheese at one artisanal dairy were monitored. Matched samples of milk, NMS, curd, and 5-d and 15-d matured cheeses were collected at different periods of the year. The DNA sequences obtained by HTS belonged to 5 phyla: Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, and Tenericutes. In milk, Proteobacteria and Firmicutes were mainly found, and several operational taxonomic units (OTU) belonging to contaminant bacteria such as Pseudomonas, Serratia, and Staphylococcus were observed. However, in NMS, curd, and 5-and 15-d cheeses, Firmicutes were principally observed where OTU of Lactococcus lactis were predominant, followed by Leuconostoc mesenteroides OTU. The results of the analysis showed high bacterial diversity in milk samples compared with NMS, curd, and 5-and 15-d cheeses, suggesting strong action of NMS in driving the characteristics of the final products.

Robiola di Roccaverano is a Protected Designation of Origin soft cheese made with goat’s milk, produced in Piedmont region (Italy). The peculiarities of this cheese are: i) the use of the raw milk, ii) the addition of a Natural Milk Starter, iii) the application of traditional techniques of production and iv) the localization of the dairies in rural area. All these aspects influence the microbial flora of final product and make interesting its investigation. Samples were collected at different moment of the cheese making process and during the different seasons. In this preliminary study, the safety and the hygiene parameters of the production were evaluated. Lactic acid bacteria, moulds and yeasts involved in cheese-making process were also enumerated. Pathogens were not found in all samples and the counts of coagulase positive staphylococci were within the standard of law. The enumeration of microorganisms of technological interest demonstrated that, nevertheless the artisanal manufacturing process applied, the dairy was able to standardize the final products.

Robiola di Roccaverano is an artisanal Protected Designation of Origin (PDO) soft cheese made with raw goat’s milk and by the addition of Natural Milk Culture (NMC) to drive the fermentation process. Cheeses collected from five different dairy plants were analyzed for their bacterial and fungal microbiota diversity. Lactococcus lactis and Leuconostoc mesenteroides were the main bacterial population, while Galactomyces candidum and Kluyveromyces marxianus constituted the core mycobiota but many other minor taxa were observed, suggesting a high level of complexity in fungal composition by these cheeses compared to bacteria population.

Robiola di Roccaverano is a Protected Designation of Origin (PDO) cheese from the Piedmont region of Italy. In this study, the mycobiota occurring during Robiola di Roccaverano production was elucidated. Samples of milk, Natural Milk Cultures (NMC), curd, 5- and 15-days ripened cheese were collected from one dairy plant and the mycobiota was analyzed by the metataxonomic approach. Milk samples showed a high diversity and Cladosporium, Kluyveromyces marxianus, Geotrichum candidum and Debaryomyces hansenii were found with higher relative abundance. This mycobiota remains quite stable in NMC and curd matrices although the relative abundance of K. marxianus and G. candidum yeasts increased significantly and shaped the fungal composition of 5- and 15-day ripened cheese.