## 3 Results and Discussion
### Phenolic and Flavonoid Contents and Antioxidant Capacity  
The predominant secondary metabolic classes in jabuticaba are the phenolic compounds [52]. Due to their antioxidant properties, phenolics and flavonoids also act to preserve the quality of beverages and for this reason, they are often evaluated in this type of product. In this study, TPC and TFC in jabuticaba wine were 2.66 \(\pm\) 0.47 g GAE\(\cdot\)L\({}^{-1}\) and 2.51 \(\pm\) 0.13 g QE\(\cdot\)L\({}^{-1}\), respectively. TPC content in the whole fruit was reported by [PERSON] et al. (2015) as being 8.15 \(\pm\) 0.52 g GAE\(\cdot\)Kg\({}^{-1}\) on a dry weight basis (dwb) [49]. The authors highlighted greater amounts of phenolic compounds in the peel (22.52 \(\pm\) 0.69 g GAE\(\cdot\)Kg\({}^{-1}\) dwb) and seed (9.86 \(\pm\) 0.47 g GAE\(\cdot\)Kg\({}^{-1}\) dwb) than in the pulp (0.2 \(\pm\) 0.01 g GAE\(\cdot\)Kg\({}^{-1}\) dwb) of jabuticaba. Similar results to those found in the present study for TPC were reported by [PERSON] et al. (2021) for jabuticaba juice (1.48 g GAE\(\cdot\)L\({}^{-1}\)) [53]. These values were similar to those described by [PERSON] et al. (2016) in Brazilian blueberry wines (TPC = 1.6 to 2.1 g GAE\(\cdot\)L\({}^{-1}\) and TFC = 1.1 to 2.6 g QE\(\cdot\)L\({}^{-1}\)) [54]. Most antioxidant compounds of jabuticaba are concentrated in its peel, and this fruit has superior antioxidant activity when compared to other fruits that are considered significant sources of bioactive compounds. During the maceration step to obtain the fermented beverages, part of these compounds migrates to the beverage [3]. The in vitro antioxidant capacity of JWE and fractions (JWF1-JWF3) can be seen in Table 2. In this study, the DPPH\({}^{\bullet+}\) and ABTS\({}^{\bullet+}\) scavenging activities were expressed in EC\({}_{50}\), which refers to the effective concentration capable of reacting with 50% of the radicals present in the solution. Therefore, the lower the EC\({}_{50}\) value, the greater the antioxidant activity. It is noteworthy that a higher and significant (\(p<\) 0.05) antioxidant capacity was observed in both ABTS and DPPH assays for the fractions when compared to the JWE. The antioxidant capacity of freeze-dried jabuticaba wine extract was 4 and 10 times lower than the standard used for the ABTS and DPPH assays, respectively. Regarding the fractions, JWF2 and JWF3 showed higher antioxidant capacities when compared to JWF1. It is noteworthy that the radical scavenging activities (EC\({}_{50}\)) obtained for JWF2 and 3 were close to those observed for the Trolox standard. The antioxidant capacity in jabuticaba wine was higher than that reported by [PERSON] et al. (2016) for fermented (EC\({}_{50}\) = 130 \(\mu\)g\(\cdot\)mL\({}^{-1}\)) and non-fermented (EC\({}_{50}\) = 262 \(\mu\)g\(\cdot\)mL\({}^{-1}\)) jabuticaba pomaces by the DPPH method [5]. [PERSON] et al. (2015) evaluated the antioxidant capacity by ABTS and DPPH assays in jabuticaba (_M. jaboticaba_) peel powder and its aqueous extract and observed values of 4.46 \(\mu\)M TroloxE\(\cdot\)mL\({}^{-1}\) and 6.42 \(\mu\)M TroloxE\(\cdot\)mL\({}^{-1}\), respectively [55]. In a previous study, 1.71 g\(\cdot\)100 mL\({}^{-1}\) of grape wine decreased free radicals level by 50%. The wine displayed higher antioxidant activity than juice made with grapes from the same lot [56]. Jabuticaba wine and its fractions displayed high antioxidant potential, as they showed approximate values to jabuticaba extracts and grape wine described by other authors. In addition, [PERSON] et al. (2022) demonstrated that the fermentation of jabuticaba can potentialize its antioxidant activity, which confers benefits to human health [3].