Highly stable Pickering emulsions stabilized by gelatin–pectin complexes: Interfacial architecture, rheological behavior, and curcumin loading and protection

Designing highly stable Pickering emulsions with common biopolymers and expanding their applications to the effective loading of lipophilic bioactives remain formidable challenges. In this study, we successfully fabricated a series of Pickering emulsions stabilized by gelatin–pectin complexes containing gelatin (1.0%, w/w) and pectin (0.1%, 0.3%, and 0.5%, w/w). Pectin incorporation significantly reduced the mean droplet size and increased the zeta-potential magnitude, with C1–P0.5 reaching < 6 μm and > 35 mV, respectively. Interfacial and bulk rheological measurements, together with cryo-SEM and LF-NMR, indicated that pectin incorporation strengthened both the interfacial layer and the continuous-phase structure, forming a multiscale reinforcing architecture. This architecture comprised a dense, viscoelastic interfacial layer and an interconnected 3D honeycomb-like scaffold, which collectively provided robust electrosteric stabilization and geometric confinement. Consequently, the high-pectin group (C1–P0.5) achieved high stability across a broad range of environmental stressors, including 180-day room temperature storage, freeze–thaw cycles, thermal treatment (60–100 °C), and wide fluctuations in pH and ionic strength (NaCl/MgCl 2 ). Furthermore, the C1–P0.3 formulation achieved a curcumin loading efficiency of > 95%, and pectin incorporation enhanced curcumin retention under UV exposure and thermal treatment. These findings provide a mechanistic basis for using simple biocomposites to develop highly stable Pickering systems for the loading and protection of sensitive lipophilic bioactives.