Storage-Induced Changes in Phenolic Profile and Antioxidant Capacity of Functional Blueberry Beverages Enriched With...

This study evaluated some physicochemical properties, phenolic profile, and antioxidant activities of blueberry-based functional beverages fortified with propolis extracts obtained using different solvents (water, glycerol, and propylene glycol). Propolis extract solvent type, storage time (12 months), storage temperature (4°C ± 2°C and 25°C ± 2°C), and packaging type significantly affected the physicochemical characteristics and bioactive properties. Moreover, sample type, storage time, and their interaction significantly affected total phenolic content (TPC), total flavonoid content (TFC), total monomeric anthocyanins (TMA), and antioxidant activities (DPPH, ABTS, and FRAP assays). In line with TPC and TFC, the propolis propylene glycol-water extract enriched blueberry beverage showed the highest antioxidant activity and TMA content. Glass packaging yielded better results in preserving TMA and maintaining the antioxidant activities of DPPH and FRAP than plastic packaging. Caffeic acid, rutin, and resveratrol were detected in all beverages. Principal component analysis showed a clear distinction based on phenolic composition and storage conditions.