A Metagenetic Insight into Microbial Diversity of Spontaneously Fermented Polish Red Wines and an Analysis of Selected Physicochemical Properties  
[PERSON]  
1 Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland; [EMAIL_ADDRESS] (M.P. ); [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (A.W.) [PERSON]  
1 Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland; [EMAIL_ADDRESS] (M.P. ); [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (A.W.) [PERSON]  
1 Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland; [EMAIL_ADDRESS] (M.P. ); [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (A.W.) [PERSON]  
2 Department of Applied Mathematics and Computer Science, University of Life Sciences in Lublin, Gleboka 28, 20-612 Lublin, Poland; [EMAIL_ADDRESS]  
[PERSON]  
3 Department of Analysis and Food Quality Assessment, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland; [EMAIL_ADDRESS]  
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the Malopolska Wine Region [4; 5]. So far, no such research has been carried out in other Polish wine regions, e.g., the Malopolska Vistula Gorge, including the Lublin Province. Nowadays, indigenous strains of yeast and lactic acid bacteria (LAB) are the preferred choice for wine production worldwide. These strains adapt better to the original environment and guarantee that the wines have sensory attributes typical of the region of origin [6; 7; 8]. The microbiome of grapes and wine depends on the grape variety, climatic conditions, agronomic practices, and the geographical location of the vineyard [9]. Grapes are the main source of non-_Saccharomyces_ yeasts, some of which are unique to wines coming from specific world regions. Some of them, such as _Torulaspora delbrueckii_, _Schizosaccharomyces pombe_, _Metschnikowia pulcherrina_, _Lachanea thermotolerans_, and _Pichia kluyveri_, have just started to be commercialised. Others, such as _Starmerella bacillaris_ (syn. _Candida zemplinina_), _Kloeckera apiculata_, _Hansenispora vineae_, _Hansenispora uvarun_, _Starmerella stellata_ (syn. _C. stellata_), _Kazachstania aerobia_, or _Schizosaccharomyces japonicus_, may follow a similar progress [10]. The fermentation of grape juice or must is a complex microbial reaction involving the sequential development of various species. Nowadays, the interest in these yeasts is growing, as they participate in the creation of the sensory attributes of wines through the production of various metabolites (alcohols, glycerol, organic acids, phenolic compounds, aromatic substances, and other products) and the secretion of enzymes (esterases, \(\beta\)-glucosidase, lipases, proteases). Numerous non-_Saccharomyces_ can also reduce the concentrations of unwanted compounds, such as ochratoxin A, ethyl carbamate, and biogenic amines [11; 12]. During the fermentation of wines, especially sour red wines, the presence of various bacteria, including LAB, has been observed. They represent genera such as _Lactobacillus, Leuconstoc_, _Lactococcus_, _Pediococcus_, _Enterococcus_, _Weisella_, and the species _Oenococcus oeni_. Some of these bacteria are involved in malcolactic fermentation (MLF). This kind of fermentation is an important process in red wine production as it reduces the acidity of wines [13]. MLF results in a rise in wine pH and microbial stability due to the removal of malic acid. Besides LAB, some acetic bacteria (AAB), e.g., _Gluconobacter_ and _Acetobacter_, have been identified in wines. They dominate in low sulphite, uninoculated wine fermentations [14].