## 1 Introduction  
The winemaking community is facing many challenges connected with climate changes that affect violculture and vinculture practices in many ways. The warming effect and consequent increase in temperature and occurrence of extreme weather, together with changes in rainfall amounts, change the short- and long-term climate structure. Among other consequences, new vinculture regions are emerging in countries of colder parts of Europe and America, while in many traditional grape-growing regions, earlier maturation results in grapes and wines with increased sugar and alcohol contents, respectively, at the same time lacking in acidity, contributing to altered and even unacceptable sensory profiles [1]. The number of scientific studies dealing with novel approaches to mitigate the mentioned negative effects of climate changes on wine quality is growing constantly. Some of these include the reduction of potassium ions that contribute to loss of acidity by sedimentation of tartrates, particular filtration techniques to reduce the initial concentration of sugars in grape must, as well as dealcoholization of wine to decrease its alcohol level [2]. Special attention is focused on particular non-_Saccharomyces_ yeasts as a potential solution for some of the abovementioned issues, since their use can significantly modulate the composition of wine. One such yeast is _Lachancea thermotolerans_, which inhabits different environments, such as grapes. Alongside its tolerance of high osmotic pressure [3], it has a moderate fermentative capacity and ethanol tolerance of around 5-9 vol % [4], so it has to be used in sequential inoculation or co-inoculation with _Saccharomyces cerevisiae_ or other strongly fermentative non-_Saccharomyces_ yeasts, such as _Schizosaccharomyces pombe_ or _Torulaspora delbrueckii_[5; 6; 7]. _Lachancea thermotolerans_ has a special ability to synthesize L-lactic acid from sugars by the action of lactic acid dehydrogenase (LDH) enzymes during alcoholic fermentation and thus simultaneously decrease the production of ethanol [8], which is a feature that can be exploited to mitigate the negative effects of overripe grapes. Metabolic pathway of L-lactic acid synthesis is still not distinguished in detail, but certain studies showed a huge phenotypic divergence regarding lactic acid production among various investigated _L. thermotolerans_ strains [9]. The activity of LDH enzymes is coded by three genes, _Ldh1_, _Ldh2_, and _Ldh3_[3]. When comparing the expression of the _Ldh_ genes of high- and low-lactate-producing strains, [PERSON] et al. [10] observed that only _Ldh2_ was up-regulated in high-lactate-producing strains, while other _Ldh_ genes were expressed at a similar level in both low- and high-lactate-producing strains. Given that lactic acid production is highly _L. thermotolerans_ strain-dependent, wide ranges of increases in its concentrations were reported as a result of its activity, from 0 to 16 g/L [11; 12; 13]. Volatile acidity is another important oenological parameter that can be affected by the activity of particular _L. thermotolerans_ strains, with the consummation of acetic acid in aerobic conditions as one of the proposed mechanisms [14]. [PERSON] et al. [15] observed a reduction in volatile acidity for about 50% after fermentation with pure _L. thermotolerans_ culture in comparison with _S. cerevisiae_ fermentation, while [PERSON] et al. [16] reported a decrease in volatile acidity of 0.25 g/L after _L. thermotolerans_ sequential inoculation. Some previous studies reported a reduced concentration of acetaldehyde in fermentation with _L. thermotolerans_ in comparison with pure _S. cerevisiae_[11; 17; 18]. Glycerol production may also be enhanced by co-fermentation with _L. thermotolerans_ and _S. cerevisiae_ compared to _S. cerevisiae_ fermentation in monoculture [5; 19]. _Lachancea thermotolerans_, like other non-_Saccharomyces_ yeasts, significantly affects the volatile aroma profile, which is one of the most important features that determines wine quality and distinctiveness.