## 3 Results and Discussion
### Content of Volatile Compounds in Must and Wine
(2019) also suggested that a lower fermentation temperature (~15 \({}^{\circ}\)C) was optimal for the effective production of the key esters during wine-making. Esters determine the fruity aroma of wines ([PERSON] et al., 2018). The main esters are fatty acid ethyl esters and acetates such as ethyl acetate, ethyl butyrate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, hexyl acetate, isoamyl acetate, isobutyl acetate, and phenylethyl acetate ([PERSON], 2010). The second major group of volatile components in Aurore wine comprised alcohols that are produced during sugar catabolism or decarboxylation and deamination of amino acids by yeast during fermentation. Compounds Such as 3-methyl-1-butanol and 2-phenylethanol were the most abundant constituents among all identified alcohols. According to the literature ([PERSON], 2010; [PERSON] et al., 2018; [PERSON] et al., 2019; [PERSON] et al., 2019) on the volatile composition of several types of white wines analyzed by solid-phase microextraction followed by gas chromatography-mass spectrometry method (SPME-GC-MS), 3-methyl-1-butanol and 2-phenylethanol were described as responsible for the characteristic fruity and rose odor of wine. In this work, the concentration of all alcohols significantly increased during the storage period. A similar effect was reported by [PERSON] et al. [PERSON] et al. (2019). Moreover, different fermentation temperature also induced changes in Aurore wine volatiles. A comparison of two major volatile alcohols at different fermentation temperatures showed a significant increase in their content when the must fermentation was carried out at 20 \({}^{\circ}\)C vs. 12 \({}^{\circ}\)C. However, the wines fermented at a lower temperature featured a higher content of amyl alcohols. [PERSON] et al. [PERSON] et al. (2019) and [PERSON] et al. [PERSON] et al. (2019) reported an increase in the concentration of all higher alcohols with increasing fermentation temperature, whereas [PERSON] et al. [PERSON] et al. (2018) showed that only the concentration of 2-phenylethanol increased in this situation. Some work reported that a level of higher alcohols below 300 mg/L confers a desirable complexity to the wine, whereas concentrations over 400 mg/L can have a negative effect ([PERSON] et al., 2019). With regard to other compounds, the number of terpen, ketones and aldehydes did not show significant variations depending on the time of storage and different fermentation temperature; only a slight decrease in the concentration of \(\beta\)-demascenone and citronellol was observed. These compounds are responsible for the violet and floral note, and fruity-flowery and citrus notes, respectively. Similar results were obtained by [PERSON] et al. [PERSON] et al. (2019). In general, raising the fermentation temperature from 12 to 20 \({}^{\circ}\)C significantly increased the concentration of almost all volatile esters and fatty acids, contrary to the content of alcohols. [PERSON] et al. [PERSON] et al. (2019) demonstrated that the content of esters and acetates decreased as a consequence of raising the fermentation temperature from 13 to 25 \({}^{\circ}\)C, which may markedly affect the aroma of white wine. In analyzed Aurore wine, the content of methyl anthranilate and 2-aminoacetophenone is well below the thresholds (1 ug/L; data not present). These compounds, key odorants responsible for \"foxiness\" and \"American grape aroma\", are typically for _Vitis rotundifolia_ or _Vitis lambrusca_ grapes, juices or wines. However, they are undetectable in _Vitis riparian_ and _Vitis cinerea_ wines ([PERSON] et al., 2019). According to [PERSON] et al. [PERSON] et al. (2019) Aurrore wine are relatively neutral in flavor but often exhibit the characteristic foxy note typical of many hybrids. Nevertheless, some author ([PERSON] et al., 2019) observed that this foxy aroma tendsto be more pronounced in wines produced in the eastern United States than in the west.