## 3 Results and Discussion
### Aroma Profile Analysis  
Table 3 lists the volatile compounds in these wines with OAVs above 0.1, indicating that these volatiles played important roles in affecting the overall aroma of these wines [6]. Furthermore, these major volatiles were grouped into seven aroma series according totheir aroma descriptors, including fruity, floral, sweet, spicy, fatty, chemical, and roasty aroma (Table 3). It can be observed that fruity and floral aroma series were the main aromatic features of both clone wines before aging (Figure 3). The major volatiles that contributed the fruity note to these wines included \(\beta\)-damascenone, ethyl acetate, ethyl hexanoate, and isoamyl acetate, whereas \(\beta\)-damascenone, 2-phenylethanol, and geraniol mainly provided the wines with a floral note (Table 3). No fruity aroma variation was observed between the clone 169 and 191 wine before and after 12-month aging (Figure 3). Meanwhile, the clone 169 wines always exhibited higher floral aroma than the clone 191 wines, both before and after aging. Nevertheless, the aging process consistently led to a significant decrease in both fruity and floral aromas. The chemical aroma was mainly contributed by ethyl acetate, isopentanol, and guaiacol in the wines, while volatile phenols including 4-vinylphenol, \(p\)-cresol, eugenol, guaiacol, and 4-vinylguaiacol played important roles in providing the roasty and spicy notes to the wine (Table 3). Before aging, no significant differences in chemical, roasty and spicy aromas were observed between the clone 169 and 191 wines (Figure 3). Through the aging process, these aged aromas were significantly accumulated in these wines. The clone 191 wines after 12 months of aging exhibited higher chemical aroma than the clone 169 wines, while the clone 169 wines showed much higher roasty aroma after aging (Figure 3). In addition, the sweet aroma in these wines mainly comprised \(\beta\)-damascenone, eugenol, and _trans_-whiskey lactone, while fatty acids, isopentanol, ethyl lactate, and ethyl decanoate determined the fatty aroma to these wines (Table 3). The clone 169 wines before aging showed a slightly higher value of fatty aroma compared to the clone  
Figure 2: (**a**) Score plot and (**b**) loading plot of principal component analysis using the detected volatiles as the variables. Y191 and Y169 represent wine made of clone 191 and 169 before aging, respectively. W191 and W169 represent wine made of clone 191 and 169 aged in Wolin oak barrel for 12 months, respectively. B191 and B169 represent wine made of clone 191 and 169 aged in Bordeaux oak barrel for 12 months, respectively. The codes of volatile compounds in the loading plot refer to Table SI. 191 wines. However, the aging process resulted in these wines having similar sweet and fatty aromas. Figure 3: Total odor activity values of aroma series in wine made of Cabernet Sauvignon clone 169 and 191 before and after aging process. Y191 and Y169 represent wine made of clone 191 and 169 before aging, respectively. W191 and W169 represent wine made of clone 191 and 169 aged in Wolin oak barrel for 12 months, respectively. B191 and B169 represent wine made of clone 191 and 169 aged in Bordeaux oak barrel for 12 months, respectively. Different letters indicate significant differences between samples for each aroma attribute at a significant level of 0.05.