Thermally reversible starch networks enhancing the performance of emulsions stabilized by zein/xanthan gum nanoparticles

Developing stable Pickering emulsions with minimal nanoparticles is challenging, as high loadings reduce efficiency, increase cost, and limit scalability. This study investigated thermally responsive corn starch (CS) networks for enhancing zein/xanthan gum (Z/XG) nanoparticle-stabilized emulsions. Incorporating CS markedly improved stability, preventing phase separation after heating at 65 and 100 °C and during storage. Creep-recovery tests showed emulsions with 0.6-0.8 % CS had low maximum strain (γ_T < 0.01) and high structural recovery, indicating strong resistance to deformation. The stabilizing mechanism was concentration-dependent: low level of CS (0.1 %) formed interfacial hydrogen-bonded films with Z/XG to prevent coalescence; intermediate levels (0.2-0.6 %) generated crosslinked, entangled starch networks in the continuous phase to reinforce stability; high CS (>0.6 %) hindered emulsification, yielding larger, polydisperse droplets. These results demonstrate that starch can substantially enhance emulsion stability by combining interfacial adsorption and bulk-phase reinforcement, offering a practical strategy for heat-stable emulsified foods with reduced nanoparticle content.