## 4 Discussion
The anthocyanin profiles were only analyzed in the wine from red grapes (Kotsifali), and the production system did not cause significant effects. However, another study [20] showed the advantages of organic grapes and wines. The researchers studied the phenolic compounds from Monastrell variety grapes obtained through organic and conventional agriculture during the last month of ripening and the wines obtained from those plants. The total amount of phenolic compounds one month before harvesting was higher for the organic grapes (97.42 mg/100 g) than the conventional grapes (44.77 mg/100 g), although these differences were not observed at the time of harvest. The content of phenolic compounds was slightlyhigher in organic wine than in conventional wine, although the differences were not significant. This was confirmed by [PERSON] et al. [42], who investigated the effect of two sustainable management practices (biodynamic and organic) on the chemical composition characteristics of Sangiovese red wines. The results confirmed the trend observed by other researchers. The differences between organic and biodynamic wines tended to disappear, and the wines were characterized by similar phenolic profiles. [PERSON] et al. [43] aimed to compare conventional, organic, and biodynamic white and red grapes and related wines to ascertain whether different agricultural practices directly influence the profiles and contents of bioactive compounds. The contents of polyphenols were measured in white (Pignoletto) and red (Sangiovese) grape berries and wines from the Emilia-Romagna region (Italy) following conventional, organic, and biodynamic agricultural practices. No significant differences were observed for the samples from the different agricultural systems. In our study, compared with the other kinds of wine examined, the wine produced using Syrah grapes contained significantly higher levels of total polyphenol, including total flavonoids. However, in another study [44] on polyphenol compounds in grape berries, Syrah cultivar and wines produced using these grapes through conventional, organic, and biodynamic agricultural methods were compared, and the total anthocyanin content during the ripening of conventionally grown Syrah grapes was significantly higher than that found during organic production. One of the most important wine phenolic compounds is that of tannins. Condensed tannins are the result of the condensation of flavanols (flavan-3-ols). Epicatechin and their derivatives are the most abundant condensed tannins in grapes and wine, followed by catechchin. In addition, they have an important role in the sensory perception of wine's astringency and bitterness. In the presented study, organic wines contain more tannins compared to conventional ones. This effect was only observed at a significant level for French wines and not Italian ones (Tables 3 and 5). This was confirmed by [PERSON] et al. (2015). They observed a higher concentration of catechin for organic (10.15 mg/L) than for biodynamic (8.8 mg/L) wines as well as of epigallocatechin for organic (5.5 mg/L) than for biodynamic (5.3 mg/L) wines [45]. Cabernet Sauvignon seems to be the richest in tannins compared to Merlot and Syrah. The ranking of wine samples after the analysis of tannin content was as follows: Cabernet > Merlot > Syrah. The experiment presented by [PERSON] et al. (2008) using these three kinds of wine confirm our findings [46]. Cabernet Sauvignon was one of the bitterest and most astringent, before Merlot, in terms of sensory evaluation. It seems that a high tannin concentration is a main key for wine taste creation. A trained sensory panel gave higher astringency ratings to high-tannin wines than to low-tannin wines of both varieties, which remained constant throughout the study [47]. The last but not the least feature of wine is color. It is created by pigments that belong to anthocyanin group. Wine with a deep, ruby color is more attractive for consumers.