Characterization of microbiota in Plaisentif cheese by high-throughput sequencing

•HTS was used to investigate the microbiota of Plaisentif cheese production.•Results showed a higher bacterial diversity in milk than in cheese.•The core microbiome of the final product is represented by the genera Lactococcus, Lactobacillus and Streptococcus.•The obtained results confirm the poor standardization of the product.

High-throughput DNA sequencing (HTS) was used in this study to investigate the microbiota of Plaisentif production, an artisanal antique cheese fabricated in the Italian Alps during the violet's blooming season. The dynamics of the microbiota was described in four production points for nine different producers. The bacteria present in all samples correspond to four phyla: Proteobacteria, Firmicutes, Bacteroidetes, and Acinetobacteria. Of these, Proteobacteria and Firmicutes were the most abundant in milk and curd whereas Firmicutes dominated in cheese samples. The results showed a higher bacterial diversity in the initial steps of cheese making (milk, curd), while the final product presented a lower number of genera mainly represented by lactic acid bacteria. In ripened cheeses, core bacterial community was composed by the genera Lactococcus, Lactobacillus and Streptococcus. Although most of the reads from the final ripened cheese correspond to few LAB, it is still possible to observe some variability between the producers. The HTS revealed that some producers used starters, even if it is not considered by the Plaisentif production's technical policy. The obtained results highlight the great potential of the HTS methodologies in the dairy industry not only from the scientific point of view but also from practical approach.