Developing anthocyanin-loaded aerogels from purple sweet potatoes using supercritical carbon dioxide drying

This study developed bioactive-rich aerogels from purple sweet potato powder (PSPP) and corn starch (CS) via supercritical carbon dioxide (SC-CO 2 ) drying. The aerogels were prepared at varying PSPP concentrations (0%, 25%, 50%, 75%, and 100%) with a complementary mixture of CS. Additionally, the purple sweet potato residue (PSPR) obtained after SC-CO 2 extraction (30 MPa, 35 °C, and 20% cosolvent concentration) was evaluated for its aerogel-forming capacity. Once aerogels were developed, anthocyanins were loaded in all samples (PSPP and PSPR), then compared in terms of total phenolic content (TPC), anthocyanin content (ANT), and antioxidant activities (DPPH, ABTS, FRAP, and ORAC). The 50% PSPP and 50% CS mixture loaded with anthocyanin extract (PSPP50-CS50-ANT) aerogel showed the highest ANT (1403 ± 10 mg C3G/100 g) and TPC (2314 ± 12 mg GAE/100 g). The developed aerogels showed a surface area of 129.4 m²/g. These findings reveal complementary functional behaviors across formulations and highlight the potential of purple sweet potato-based aerogels as eco-friendly carriers for natural colorants and nutraceutical ingredients.