Structurally stable zein–xanthan–starch Pickering emulsions enable quercetin protection and fat replacement in processed meat

Quercetin-loaded Pickering emulsions were stabilized by biopolymer nanoparticles. • The emulsions exhibited oxidative stability under thermal, UV, and saline stresses. • The emulsions retained structural integrity and viscoelasticity during processing. • 80% of fat in processed meat was replaced by the emulsions without sensory loss. • The emulsions enhanced hardness and mildly altered water mobility in the product. Although Pickering emulsions show great potential as fat substitutes, achieving low formulation cost and high bioactive retention under complex processing stresses remains a major challenge. In this study, quercetin-loaded zein/xanthan/corn starch (QZXC) particles were developed to fabricate food-grade Pickering emulsions. QZXC emulsions exhibited excellent environmental stability, maintaining high quercetin retention (81.8% for 65 °C and 81.7% for 100 °C) and antioxidant activity after thermal treatment, ultraviolet irradiation, and high-salt exposure. Rheological analyses demonstrated that emulsions preserved their viscoelasticity and structural integrity under processing stresses. QZXC emulsions successfully replaced up to 100% of fat in processed meat with acceptable cooking loss and sensory quality, whereas the 80% replacement achieved optimal texture and antioxidant performance. LF-NMR and texture profile analyses further confirmed that water mobility and product structure were minimally affected during storage. These findings demonstrate that QZXC emulsions are promising multifunctional fat replacers with enhanced stability, bioactive protection, and nutritional functionality.