摘要

Quercetin (Que), a highly bioactive component of flavonoids, has extremely high hydrophobicity (which limits its use in the food industry. In this research, wheat protein hydrolysate (WPH) and Que were used to construct composite nanoparticles, and sugar beet pectin (SBP) was added as a natural emulsifier to construct WPH/Que/SBP composite emulsion. The main findings included: WPH could increase the solubility of Que from 8.13 μg/mL to 126.39 μg/mL. During emulsion-based encapsulation, the excellent emulsifying properties of SBP may be beneficial to its dominance in the competition while compensating for the deterioration of emulsifying performance of WPH, causing the decreases in the contents of WPH and Que at the interfaces. With the addition of SBP, the particle size of the composite emulsion decreased significantly, with the average particle size in the surface area of the neutral and the acidic emulsions decreasing from 2.35 μm and 1.03 μm, respectively, to 0.56 μm and 0.76 μm. The composite emulsion exhibited good short-term storage and thermal stability. A pH around the PI value may be beneficial for the complexation of SBP and WPH, thereby, the overall performance of the acidic composite emulsion was better than that of the neutral emulsion.