Sustainable valorization of blanched artichoke by‑products via simplex‑centroid mixture design for optimized phenolic and flavonoid recovery

Artichoke (Cynara scolymus) processing generates substantial by-products, including outer bracts (OBW), inner bracts (IBW), and stems (STW), which are rich in bioactive compounds. This study optimized the extraction of phenolic and flavonoid compounds from blanched artichoke residues using response surface methodology and a simplex-centroid mixture design. STW showed the highest extraction yield (12.00%) and total phenolic content (20.72 mg GAE/g dw), whereas IBW presented the highest flavonoid content (584.69 mg QE/g dw) and DPPH antioxidant activity (250.51 μmol TE/g dw). The optimal mixture, composed of 25.53% IBW and 74.47% STW, achieved a desirability value of 0.852. ABTS and FRAP assays confirmed the antioxidant potential of the optimized blend. HPLC-DAD analysis identified seven phenolic compounds, with chlorogenic acid as the predominant compound. These findings highlight blanched artichoke residues as promising sources of bioactive compounds for food applications.