Ultrasound enhances phenolic and mineral extraction from lemon-chokeberry functional juice

This study investigates the effect of ultrasound-assisted extraction (UAE) on the recovery of phenolic compounds, antioxidant activity, and mineral content in a lemon juice system fortified with chokeberry ( Aronia melanocarpa ) powder. Conventional extraction (CE) and UAE were compared over a processing time range of 0–30 min to evaluate extraction efficiency and underlying mechanisms. UAE significantly enhanced total phenolic content (TPC) and total flavonoid content (TFC), with increases of approximately 18% and 15%, respectively, compared to CE ( p < 0.05). The improvement was attributed to acoustic cavitation, which promotes cell wall disruption and enhances mass transfer. UAE resulted in a marked increase in hydroxycinnamate derivatives (≈ 25%) and flavanones (≈ 15%), indicating enhanced release of key antioxidant compounds. Antioxidant activity, determined by DPPH and ABTS assays, showed a strong positive correlation with phenolic content, confirming that phenolic compounds are the primary contributors to radical scavenging capacity. UAE also increased the extraction of selected minerals, particularly Fe and Mn, indicating improved release of matrix-bound components. The acidic nature of lemon juice further contributed to extraction efficiency by stabilizing phenolic compounds and enhancing cavitation effects. Overall, UAE proved to be a rapid and effective technique for improving the functional properties of chokeberry-enriched lemon juice. These findings highlight the potential of combining ultrasound technology with acidic fruit matrices to develop functional beverages with enhanced bioactive profiles.