Effects of chlorogenic acid on the interfacial properties and physical stability of sunflower oil body emulsions: Insights from a reconstructed protein-emulsion model

Abstract

The stability of sunflower oil body emulsions is mainly governed by interfacial phospholipids and proteins, whereas the role of endogenous polyphenols remains unclear. This study aimed to evaluate the effects of chlorogenic acid (CGA) on physical stability. Reconstructed oil body proteins (ROBPs) and emulsions (ROBEs) were used as model systems. CGA decreased β-turn content from 43.06% in 0 mg-CGA-ROBPs to 26.50% in 38 mg-CGA-ROBPs. For ROBPs, as CGA addition increased from 0 to 38 mg, the emulsifying activity index increased from 27.91 to 77.32 m2/g and the emulsion stability index from 11.04 to 57.37 min. At 38 mg CGA, ROBEs reached a zeta potential of −47.13 mV and an interfacial protein concentration of 43.18 mg/m2, together with increased viscosity and viscoelasticity and improved physical stability. These findings provide insight into how endogenous CGA affects protein conformation and emulsion stability and may guide the formulation of stable oil body-based foods.