## 3 Results and Discussion
### Influence of Wine Region  
In terms of the geographical origin of wine, certain regions are particularly famous for their wines. Elemental fingerprinting presents one attempt to measure regionality [51]. The other approach is based on sensory properties and volatile components. Wine as a complex matrix contains volatile and non-volatile components that affect the perception of aromas, taste and mouthfeel and, despite the similar chemical characteristics, sensory characteristics can be very different. Studies by [PERSON] et al. [52], [PERSON] et al. [53] and [PERSON] et al. [54] revealed the fact that differentiation of wines of the same variety, but of different appellations of origin, can be based on sensory properties. Phenolics have also been proposed as chemical markers to establish cultivar authenticity and geographical origin of grapes [54; 55]. Slovakia, however, the small country, presents a heterogeneous environment especially in terms of geological and soil conditions. A reflection of this fact can be found in the chemical composition of grapes cultivated in different wine regions. The acidic character of wine was chosen as a group distribution of carboxylic acids (including malic acid, tartaric acid, lactic acid, etc.) in order to classify South Moravian wines [56]. In our study, the possible influence of wine regions on individual chemical parameters was also statistically evaluated. The PCA outcome is summarized in the ordination diagram (Figure 2). The classification of wines as a group of malic acid, tartaric acid, total acids, glucose, fructose, total polyphenolics and antioxidant activity was chosen as the experimental object. The PCA analysis showed similarities regarding the wine-growing region and grape varieties. The first two axes (shown in the diagram) explain 61% of the total variation of chemical composition. The similarities were observed in wines from the same region, however, not in all three wine varieties this trend was confirmed. Data obtained from wines of Malokarpatska and Juznoslovenska wine regions showed similarities. Clearly distinguished wine-growing regions were Nitrianska and Stredoslovenska. The differences in chemical parameters among these wine regions in relation to the wines indicate the extent to which the subgroups share similar characteristics of wine acidity and sweetness. The most important factor that presented the main descriptor parameter for the distinction among wine-growing regions was the content of organic acids (total acids, tartaric, malic acid and lactic acid). The acid composition and their concentration were also found to correlate with the grape variety, region, processing techniques (especially alcoholic and malolactic fermentation) and aging process [56; 57]. Statistical tests confirmed significant differences in selected chemical parameters in relation to the wine-growing regions (Figure 3). Differences among regions were confirmed in total acids (F\({}_{3,8}\) = 6.7, \(p\) = 0.0142), caused mainly by differences between the Nitrianska and Ju\(\acute{\text{n}}\)noslovenska wine regions (t\({}_{8}\) = 4.37, \(p\) = 0.01). Content of tartaric acid was also statistically different (F\({}_{3,8}\) = 9.8, \(p\) = 0.0046) due to the low content in the Nitrianska wine region compared to the values in Ju\(\acute{\text{n}}\)noslovenska (t\({}_{8}\) = 4.2, \(p\) = 0.013) and Stredoslovenska wine region (t\({}_{8}\) = -5.1 \(p\) = 0.004). In the case of malic acid (F\({}_{3,8}\) = 21.7, \(p\) = 0.0003), significant differences were discovered between Ju\(\acute{\text{n}}\)noslovenska and every other region (t\({}_{8}\) = 5.1; 3.3; 7.9, \(p\) < 0.05, for Malokarpatska, Nitrianska and Stredoslovenska, respectively) as well as between Nitrianska and Stredoslovenska wine regions (t\({}_{8}\) = 4.6 \(p\) = 0.008).