Regional microbial content of fermented traditional and industrial East Mediterranean sausages from the islands of Cyprus and Mytilini

<b>Objective:</b> To characterize the microbial biodiversity of fermented sausages from the East Mediterranean islands of Cyprus and Mytilini, and to identify differences between the microbial diversity of traditionally and industrially produced Cypriot sausages. <b>Method:</b> The microbial diversity of thirty sausages from Cyprus and Mytilini (traditionally and industrially produced) was analyzed using high throughput sequencing (HTS) (amplicon sequencing) of 16S rRNA gene and ITS loci fragments. By applying microbial signature detection and machine learning algorithms, we identified key microbes that distinguish traditionally produced sausages from those produced industrially. Focusing on selected microbial taxa and using interaction network analysis, we identified associations among the sausages' microbiota that may affect the shaping of the sausages' microbial consortia. <b>Results:</b> Cypriot and Mytilini sausages indicated increased relative representation of <i>Lactobacillus</i> and <i>Leuconostoc</i>. Cypriot sausages were distinguished by the presence of the fungi <i>Debaryomyces hansenii</i> and <i>Candida spp.</i>, whereas Mytilini sausages by the bacteria <i>Lactococcus</i> and <i>Streptococcus</i>. Traditionally produced sausages from the Pitsilia region of Cyprus were differentiated by the presence of the species <i>Lactobacillus helveticus</i>, whereas industrially produced sausages were differentiated by the species <i>Leuconostoc mesenteroides</i>. Focusing mainly on <i>Lactobacillus</i> and <i>Leuconostoc</i>, negative associations with pathogenic bacteria, such as <i>Salmonella</i>, and spoilage fungi, such as <i>Fusarium poae</i>, were revealed. <b>Conclusion:</b> The present metataxonomic analysis provided insights into the microbial communities that characterize Cypriot and Mytilini sausages. The findings provide an indication that the microbial diversity might be applied as an additional marker of Cypriot sausages' authenticity.