Stabilization of blueberry anthocyanins by glycated fish gelatin: Unveiling binding behavior and conformational changes

This study investigates the interaction between glycated fish gelatin (FG) and blueberry anthocyanins (ACNs) and its impact on ACN stability. Results demonstrated that glycation significantly enhanced FG's binding capacity to ACN, with FG glycated with fructose for 60 min (FG-Fru-60 min) achieving the highest binding (169.11 mg/100 g). Spectroscopic analyses confirmed this strengthened binding via non-covalent interactions. Stability assays revealed that FG-Fru provided significantly superior protection compared to non-glycated FG and inulin-glycated FG (FG-Inu). Under various stress conditions including heating (100 °C, 2 h), ultraviolet (UV) irradiation (120 h), ascorbic acid exposure (144 h), pH 9 (10 d), simulated digestion, and dark storage (25 °C, 70 d), ACN retentions in the FG-Fru-60 min/ACN complex were 35.31%, 38.49%, 46.38%, 36.40%, 40.19%, and 42.30%, respectively, which significantly exceeded those of free ACN, non-glycated FG/ACN, and FG-Inu-60 min/ACN complexes. Conclusively, glycated FG enhances binding to ACN through non-covalent interactions, thereby improving ACN stability.