Elucidation of the relationship between milk protein-stevioside interactions and interfacial layer properties based on multi-spectroscopy and interfacial rheology

Meng Wang; Zihao Wei; Yujin Li; Ziheng Jin; Changhu Xue

doi:10.1016/j.foodchem.2024.142512

Elucidation of the relationship between milk protein-stevioside interactions and interfacial layer properties based on multi-spectroscopy and interfacial rheology

Food Chem. 2024 Dec 16:468:142512. doi: 10.1016/j.foodchem.2024.142512. Online ahead of print.

Authors

Meng Wang¹, Zihao Wei², Yujin Li¹, Ziheng Jin³, Changhu Xue¹

Affiliations

¹ State Key Laboratory of Marine Food Processing & Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China.
² State Key Laboratory of Marine Food Processing & Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China. Electronic address: weizihao@ouc.edu.cn.
³ Henan Zhongda Hengyuan Biotechnology Stock Co., Ltd, Luohe 462600, China.

PMID: 39700803
DOI: 10.1016/j.foodchem.2024.142512

Abstract

The intricate interactions between stevioside (STE) and milk protein (mixtures of whey protein isolate and sodium caseinate, WPI/SC) as well as interfacial stabilization mechanisms were investigated. At the molecular scale, it was observed that the incorporation of the steviol hydrophobic skeleton enhanced the surface hydrophobicity of WPI/SC (from 1560.73 to 2175.63), favoring the reduction of the energy barrier for adsorption. At the mesoscopic scale, the analysis of adsorption kinetics and interfacial dilatational rheological response revealed that STE and WPI/SC had a synergistic effect on the attenuation of oil-water interfacial tension, with the lowest value of interfacial tension of 9.46 mN/m. Meanwhile, at low concentrations of STE, the WPI/SC-STE complexes unfolded and self-assembled at the interface to form a spring-like interfacial layer that relaxed in response to external deformation. In contrast, at high concentrations of STE, it gradually replaced WPI/SC-STE complexes at the interface and destabilized the interfacial layer.

Keywords: Interfacial dilatational rheology; Lissajous plots; Non-covalent interaction; Oil-water interface; Spring-like interfacial layer; Stevioside.