Introduction
Pomegranate is known for its health-promoting effects, including its role in preventing heart disease and diabetes. Huge wastes of over-ripe and secondary quality pomegranate prompt the need to improve the quality of associated processed products. Therefore, methods and uses of fruit processing should be advanced. Pomegranate wine dispensation has been recently elaborated as a novel approach to Punica granatum L exploitation (Lan et al., 2017).
During fermentation, significant characteristic flavor formation and volatile composition alterations occur, resulting in fragrant, alluring, and unique wines. The pomegranate wine’s comprehensive real-time change of antioxidant elements and its characteristic flavor profile during the entire aging and fermentation process requires further studies. This research’s primary objective was to investigate the flavor profile and antioxidant changes of pomegranate wine through the process of fermentation and aging.
Methodology
Based on the article, the total anthocyanin content (TAC), superoxide anion, DPPH free radical, total phenols content (TPC), phenolic profiles, and hydroxyl radicals scavenging activity were examined throughout the entire pomegranate winemaking procedure. The overall aromas and taste quality, as well as dynamic flavor ingredient changes in the wine, were also monitored during processing.
E-tongue and E-nose technologies were utilized in detecting and analyzing even the slightest variation in aroma and taste of different samples. Other quality parameters, such as titratable acidity (TA), pH, organic acid profiles, alcohol content, and total soluble solids (TSS), were also investigated. Three independent trials were carried out, and the data obtained were evaluated statistically using the variance (ANOVA) method. The ANOVA technique employed the SPSS 18.0 software. In situations where significant differences between samples were distinguished, an LSD assessment was applied.
Results
Anthocyanin swiftly decreased until the fourth day and then mildly reduced to the end of the preparation process. TAC exhibited a significant loss after fermentation (from 53.71 ± 3.06 to 23.02 ± 1.09 mg/L) (Lan et al., 2017). The results also indicated that the scavenging activity of superoxide anion free radical slightly decreased after the fermentation and aging process (Lan et al., 2017). The processed pomegranate wine still contained potent hydroxyl radical scavenging activity.
The scavenging capacity of the DPPH free radical dropped initially and then increased as the fermentation process continued. In the final aging stage, the DPPH scavenging activity remained relatively stable. The TPC’s concentration fluctuated significantly during fermentation and became gradually stable during the aging period. Using the e-nose technology, significant differences were observed in the samples before and after fermentation. On the other hand, the E-tongue signal results decreased in all potentiometric chemical sensors, except one.
Discussion
Anthocyanin has a significant function in the antioxidant activity and fascinating color of pomegranate wine. The TAC changes during the process could be because of anthocyanin degradation and polymerization interactions and reactions between anthocyanin and other phenolic compounds (Lan et al., 2017). The O2 free radical does not directly induce an oxidative reaction, but it promotes the construction of an active OH free radical. The potent hydroxyl radicals were mainly due to specific bioactive composites that mop up free radicals in the wine. The DPPH scavenging ability’s variation is linked to the transformation of polyphenols content.
The manufactured wine maintained a considerable capacity to reduce and inhibit DPPH compared to red wine. The TPC variation was due to the oxidation and hydrolysis of native polyphenols. The significant E-nose sample differences could be attributed to the formation of similar volatile substances and novel volatilities in various concentrations. The E-tongue outcomes show that the sourness of the wine weakened at the end of its manufacturing course.
Conclusion
The antioxidant capacity, flavor characteristics, and phenolic profile changes were investigated for pomegranate wine during winemaking. The survey proved that the wine had an adequate antioxidant scavenging capacity for free radicals, regardless of the minimal losses in antioxidant activity and polyphenols after fermentation. The study also proved that pomegranate wine has a high phenolic compounds amount and displayed outstanding flavor characteristics. The TPC and radical scavenging trend during fermentation and aging designate that the wine has crucial antioxidant abilities, making it an excellent healthy beverage for human beings.
Reference
Lan, Y., Wu, J., Wang, X., Sun, X., Hackman, R., Li, Z., & Feng, X. (2017). Evaluation of antioxidant capacity and flavor profile change of pomegranate wine during fermentation and aging process. Food Chemistry, 232, 777-787. Web.