Polyphenol Powders from Ginkgo biloba L. and Clitoria ternatea L.: Influence of Drying Techniques and Carriers on Antioxidant Capacity and Polyphenol Release Profiles

This study evaluated the impact of the drying and carrier type on the physicochemical and functional properties of <i>Ginkgo biloba</i> L. and <i>Clitoria ternatea</i> L. extracts and their blends, at ratios of 1:1, 1:2, and 2:1 (<i>w</i>/<i>w</i>). Extracts were obtained using water as a green solvent and dried by freeze- or spray drying with maltodextrin or inulin. Powders were characterized for moisture content, water activity, color, polyphenol composition (HPLC-MS/MS), and antioxidant capacity (Folin-Ciocalteu, TEAC ABTS, FRAP). Spray-dried samples exhibited lower moisture content and water activity, while freeze-drying ensured higher polyphenol levels. The 1:1 (<i>w</i>/<i>w</i>) blend with inulin showed the most favorable balance between stability and antioxidant capacity, indicating synergistic effects. This formulation was selected for pilot-scale processing and encapsulated into hard gelatin capsules, which demonstrated rapid polyphenols release under simulated gastric conditions. The findings highlight the potential of spray-dried polyphenol-rich powders as standardized ingredients for immediate-release dietary supplements.