Tetragenococcus koreensis is part of the microbiota in a traditional Italian raw fermented sausage

• Tetragenococcus koreensis is present at high levels in a traditional Italian sausage.
• Sausage isolates were more tolerant to NaCl (up to 15% w/v) than the type strain.
• The isolates did not produce histamine and tyramine.
• Intra-species genotypic and phenotypic diversity was highlighted.
• Peptide profile modification was strain-dependent in broth cultures.

This study reports the isolation of Tetragenococcus koreensis, a bacterial species currently represented only by the type strain isolated from kimchi, from a raw fermented and ripened Italian sausage, Ventricina Vastese, all over the ripening period of five months. Rep-PCR genotyping showed that different T. koreensis strains, identified by sequencing of the 16S rRNA gene, were present in the same production batch. Tests on representative isolates showed intra-species physiological variability and the possession of phenotypic traits relevant for the production of fermented sausages, i.e. ability to grow at high salt concentrations, to induce some changes in the peptide profile of the culture medium and inability to produce histamine and tyramine, confirmed by the absence of the respective decarboxylase genes. Therefore the opportunity to further investigate the suitability of T. koreensis as a starter for fermented meat products was suggested.