Fermented foods: lessons learned from metagenomics

Thanks to the standard microbiology protocols of isolation and culturing, hundreds of strains have been isolated from fermented foods throughout the last decades, and phenotypic traits linked with pro-technological properties and health claims have been investigated. However, culture-independent metagenomic analyses have revealed an unexpected microbial diversity in foods fermented spontaneously or by undefined starter cultures. Here, we report the most groundbreaking advancements in the understanding of fermented foods ecology by presenting case studies where metagenomics has been applied, contributing to identifying novel species in silico or to deciphering the microbiome structure associated with spontaneous fermentations. We also highlight the potential of metagenomics in supporting the identification of potential probiotics and discuss the future ahead, particularly focusing on the integration of multi-omics approaches.