# Exploring Red Wines from the Drama Region: A Chemical, Sensory, and Terroir Insight
## 3 Results and Discussion
### Phenolic Content and Profile of Wines
Another important factor influencing terrori expression is the water status of the vines, which is influenced by weather factors, including evapotranspiration and rainfall [48]. As it is obvious from Figure 1, the Nevrokopi vineyard is characterized by increased rainfall during the ripening period, as well as a lower mean temperature. Regarding Agiorgitiko wines, those from Perichora exhibited the highest values. The Cabernet Sauvignon wines showed lower variance in the total phenolic content quantified than the other cultivars. Moreover, there is a high variance in the quantity of individual phenolic compounds among the locations for each cultivar. Resveratrol represents another compound of high interest present in wine since it is known to have a positive effect on cardiovascular diseases [49; 50; 51]. It is present in higher than 1.65 \(\upmu\)g/mL in Merlot wines from Nevrokopi, followed by Agora and Kali Vrisi. The rest of the samples contained less than 0.5 \(\upmu\)g/mL. According to the earlier research, wines from vineyards situated at higher elevations (over 1500 m) had a higher phenolic content, including resveratrol, than those at lower elevations [52]. Correlations performed among must physicochemical parameter values and TPI and individual phenolics revealed the weight of 100 grapes having a strong association with gallic acid (\(-\)0.697, \(p\) = 0.025), procyanidin B2 (\(-\)0.842, \(p\) = 0.002), catechin (\(-\)0.697, \(p\) = 0.025), procyanidin B3 (\(-\)0.733, \(p\) = 0.016), isorhamnetin-3-O-D-glucose (\(-\)0.777, \(p\) = 0.003), and luteolin (\(-\)0.779, \(p\) = 0.008). This behavior can be explained by the fact that these compounds are mainly present in the grape's skin; by decreasing the grape's weight, there is an increase in the grape's skin surface and consequently the amount of these compounds that are able to be extracted in the must and then in wine. Moreover, must acidity was associated with hyperoside (0.770, \(p\) = 0.009), whereas must pH with quercetin-3-O-glucose (\(-\)0.891, \(p\) = 0.009) and resveratrol (\(-\)0.685, \(p\) = 0.029). Regarding wine physicochemical parameters, p-coumaric acid showed a strong association with A\({}_{520\text{nm}}\) (0.842, \(p\) = 0.002), A\({}_{420\text{nm}}\) (0.758, \(p\) = 0.011), color intensity (0.733, \(p\) = 0.016), and alcohol content (0.632, \(p\) = 0.050). Indeed, the literature reported a strong co-pigmentation effect of p-coumaric acid and color development at 520 nm [53]. Moreover, malic acid correlates with quercetin-3-O-glucose (\(-\)0.726, \(p\) = 0.017), isorhamnetin-3-O-D-glucose (0.658, \(p\) = 0.038), and luteolin (0.667, \(p\) = 0.035). In addition to the effect in wine color variation [53], phenolics such as catechin, caffe acid, and quercetin can be bonded to aroma compounds [54]. The literature reports that the abovementioned phenolics are linked to the formation of compounds such as isobutyl methoxypyrazine producing a bell pepper aroma to wines [55], 3-mercaptoethanol and 3-mercaptoethanol acetate correlated with tropical and passion fruit aromas detected in Sauvignon blanc wines [56; 57], and ethyl decanoate producing fruity and floral aromas in wines [55].