## 3 Results and Discussion
### Volatile Compounds  
The HS-SPME-GC-MS analysis identified a total of 56 volatile compounds in all the analyzed wines, among which 34 showed significant differences (\(p<0.05\)). The chemical profile consisted of 10 chemical families: 27 esters, 11 alcohols, 4 aldehydes, 4 alkanes, 3 ketones, 3 norisoprenoids, 1 organic acid, 1 terpene, 1 dioxolane, and 1 acetal, with esters being the predominant chemical group contributing to _Fondillon_ odor and aroma (Table S3). No clear trends were found for the effect of the \"_solera_\" factor on the content of volatile compounds; thus, general comments will be presented in this section. Esters are aromatic compounds providing and enhancing fruit aromas in wines; in general, the most important ones are ethyl fatty acid esters and acetates [38]. Diethyl butanetioate, ethyl octanoate, and ethyl acetate were the most abundant esters in the nine _Fondillon_ samples under study and contributed to their red berries fragrance (Table 3). Considering all the above, it can be concluded that the DPPH\({}^{\bullet}\) method seemed the most suitable one to study the antioxidant activity of _Fondillon_, and that the antioxidant activity in this type of wine was clearly linked to the total anthocyanins content. Another important conclusion of this section was that the _Fondillon solera_ 1960 was the most special sample because it had the highest contents of phenolic compounds, condensed tannins, and anthocyanins, which led to (i) the highest values of antioxidant activity (all three methods under study, ABTS\({}^{\bullet+}\), FRAP, and DPPH\({}^{\bullet}\)), and (ii) the highest values of color density and intensity, as defined by intense red and blue colors. ### Volatile Compounds  
The HS-SPME-GC-MS analysis identified a total of 56 volatile compounds in all the analyzed wines, among which 34 showed significant differences (\(p<0.05\)). The chemical profile consisted of 10 chemical families: 27 esters, 11 alcohols, 4 aldehydes, 4 alkanes, 3 ketones, 3 norisoprenoids, 1 organic acid, 1 terpene, 1 dioxolane, and 1 acetal, with esters being the predominant chemical group contributing to _Fondillon_ odor and aroma (Table S3). No clear trends were found for the effect of the \"_solera_\" factor on the content of volatile compounds; thus, general comments will be presented in this section. Esters are aromatic compounds providing and enhancing fruit aromas in wines; in general, the most important ones are ethyl fatty acid esters and acetates [38]. Diethyl butanetioate, ethyl octanoate, and ethyl acetate were the most abundant esters in the nine _Fondillon_ samples under study and contributed to their red berries fragrance (Table 3). In the same way, alcohols played an important role in the wines under analysis; they can come from the grapes themselves or from the yeast metabolism [38]. In _Fondillon_, the predominant ones were isoamyl alcohol, 2-methyl-1-butanol, and phenethyl alcohol and were responsible for fruity, floral, and honey notes. The norisoprenoids are key compounds in the wine aroma profile and belong to the carotenoid metabolism. During wine aging, glycosidically-bound aroma compounds coming from the carotenoid metabolism can be subjected to slow acid hydrolysis rendering norisoprenoids such as 1,1,6-trimethyl-l,2-dihydronaphthalene (TDN) and vitispirane isomers [38; 39]. TDN has been reported as the compound responsible for the kerosene bottle-aged character of Riesing wines [38; 40], while vitispirane contributes to nut flavor notes [41]. There was no significant effect of the \"_solera_\" factor on the contents of (i) TDN (range 0.06 and 0.19 mg L\({}^{-1}\), with a mean of 0.13 mg L\({}^{-1}\)) and (ii) vitispirane (range 0.08 and 0.20 mg L\({}^{-1}\), with a mean of 0.14 mg L\({}^{-1}\)).