## 4 Discussion
We have shown that the house microbiota predominated over the deliberately added starter and adjunct cultures in the cheese microbiota of five producers. The only exception was cheese B, whose microbiota consisted exclusively of bacteria of starter and adjunct cultures. This finding is noteworthy; however, the question remains as to whether this observation can be attributed to effective hygiene practices or to the significantly higher salinity of the product that may affect microbial growth. Proteobacteria were the most abundant bacteria detected by 16S rRNA gene sequencing in the total microbiota in cheeses from five of the six producers. The main representatives included psychotrophic bacteria such as _Psychrobacter_ and _Pseudoalteromonas_, \"marine bacteria\" such as _Marinomonas_, various species of the genus _Vibrio_, as well as other Proteobacteria such as _Cobelia_ and _Celerinatantomonas_. It has been shown that _Psychrobacter_ can significantly reduce the bacterial community and therefore, successfully implant itself into cheese, regardless of its inoculation level [7; 22]. This bacterium may contribute positively to flavour development by producing volatile aromatic compounds such as aldehydes, ketones and sulphur, thereby affecting the aromatic properties of the cheese [8; 22; 23]. Various _Pseudoalteromonas_ species have been identified in soft and semi-hard pasteursied and unpasteurised cheeses, as well as on the surface of smear-ripened cheeses [24; 25; 26; 27]. This bacterium has been found to possess cold-adapted enzymes that contribute to the flavour development of cheeses during ripening and storage at low temperatures [7; 23]. Generally, managing the presence of psychrotrophic bacteria is essential in cheese production to ensure desirable sensory attributes, as some species may lead to spoilage by producing off-flavours [28]. Bacteria of the genus _Vibrio_ have been reported to be among the most abundant species in Epoisses cheese at the end of the ripening [16]. Similarly, _Celerinatantimonas_ spp. and _Cobenia marina_ were found in traditional cheese from south Brazil; however, their effect on cheese characteristics has not been described [29]. Proteobacteria were also among the bacteria that were captured with the highest frequency by culture methods. Consistent with the results of 16S rRNA gene sequencing, distinct isolates of the genus _Vibrio_ and _Psychrobacter_ were obtained. However, other isolated bacteria from the phylum Proteobacteria, such as _Morganella_, _Shewanella_, _Enterobacter_, and _Citrobacter_, were hardly detected by 16S rRNA gene sequencing. These bacteria are frequently isolated from the surfaces of food processing areas in the food industry, where they can easily survive in the form of biofilms, and their presence should be monitored [8; 30]. Apart from starter cultures, the only representatives of the phylum Firmicutes identified by 16S rRNA gene sequencing were bacteria of the genera _Vagococcus_ and _Marini-lactobacillus_. Correspondingly, distinct isolates of _Vagococcus_ and _Marini-lactobacillus_ were retrieved by cultivation. The presence of these bacteria in smear-ripened cheeses has already been reported [31]. It has also been shown experimentally that the defined isolate of _Marini-lactobacillus_ produced acetate from lactate during ripening in Brie-type model cheeses, and the _Vagococcus lutrae_ isolate produced acetate from lactose under aerobic conditions, thereby influencing the properties of the model product [32; 33]. Different strains of staphylococci were obtained by cultivation in our study. In addition to _S. xylosus_ and _S. aquorum_, which can be considered technologically utilised bacterial cultures, isolates of _S. epidermidis_, _S. capitis_, _S. hominis_, and _S. saprophyticus_ were also recovered. Staphylococcus are known to thrive in low pH environments and high salt concentrations, and the presence of certain strains in food products may indicate secondary contamination originating from human carriers [34; 35].