Effect of tannic acid modification on the interface and emulsification properties of zein colloidal particles.

Abstract

Interface modification driven by supramolecular self-assembly has been accepted as a valuable strategy for emulsion stabilization enhancement. However, there has been a dearth of comparative research on the effect of simple complexation and assembly from the perspective of mechanism. This work selected zein and tannic acid (TA) as representative protein and polyphenol modules for self-assembly (coined as TA-modified zein particle and TA-zein complex particle) to explore the surface properties, interfacial behavior, as well as the stability of constructed Pickering emulsions to obtain the regulation law of different modification methods on the interfacial behavior of colloidal particles. The results demonstrated that TA-modified zein colloidal particles stood a chance of improving emulsifying properties. When the TA concentration was 3 mmol/L, the optimized TA-modified zein particle was nano-sized (109.83 nm) and had advantageous interfacial properties, including sharply reduced surface hydrophobicity, and low diffusion rate at the oil/water interface. As a result, the shelf life of Pickering emulsion containing 50% oil phase was extended to 90 days. Through multi-angled research on the properties of the interfacial membrane, improvement of emulsion stability was due to the formation of viscoelastic interfacial film which resulted from the decrease of absorption rate between particles and interface. Using refined regulation to study the role of different sample preparation methods from a mechanistic perspective. Overall, this study has provided a reference for TA to regulate the surface properties and interface behavior of zein colloidal particles, enriched the understanding of colloidal interface assembly, and provided a theoretical basis for the quality control of interface-oriented food systems. This article is protected by copyright. All rights reserved.