Pomegranate juice functional constituents after alcoholic and acetic acid fermentation

Abstract

In this study, a two-stage process, alcoholic and acetic acid fermentation was applied for the first time to fresh pomegranate juice to examine its effect on the phenolic content together with the antioxidant activity of the fermented product(s). The total phenol content of the juice was not greatly affected during the process. On the contrary, the total anthocyanin content fluctuated; the alcoholic product was 10-fold poorer while the end product was as rich as the fresh juice. Both fermented products had qualitatively similar HPLC-DAD-MS profile of phenolic constituents with that of the starting material but lower content (e.g. 49 and 32% of individual phenolic acid derivatives remained, respectively). The acetification product retained 44% and 37% of the fresh juice activity to scavenge the DPPH• and reduce cupric ions, respectively. These characteristics along with attractive red colour suggest that the end product is a potential source of functional constituents.

Keywords

• Pomegranate vinegar
• Total phenol content
• Total anthocyanin content
• DPPH•
• CUPRAC
• Colour