Viscoelasticity of olive oil/water Pickering emulsions stabilized with starch nanocrystals

Xiaoli Qian; Yu Lu; Wenyuan Xie; Defeng Wu

doi:10.1016/j.carbpol.2019.115575

Viscoelasticity of olive oil/water Pickering emulsions stabilized with starch nanocrystals

Carbohydr Polym. 2020 Feb 15:230:115575. doi: 10.1016/j.carbpol.2019.115575. Epub 2019 Nov 7.

Authors

Xiaoli Qian¹, Yu Lu¹, Wenyuan Xie², Defeng Wu³

Affiliations

¹ School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu Province, 225002, PR China.
² School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu Province, 225002, PR China; Institution of Innovative Materials & Energy, Yangzhou, Jiangsu Province, 225002, PR China.
³ School of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu Province, 225002, PR China; Provincial Key Laboratories of Environmental Engineering & Materials, Yangzhou, Jiangsu Province, 225002, PR China. Electronic address: dfwu@yzu.edu.cn.

PMID: 31887857
DOI: 10.1016/j.carbpol.2019.115575

Abstract

The olive oil-in-water Pickering emulsions stabilized with starch nanocrystal (SNC) were prepared for the morphological and rheological studies. Different kinds of shear flows were applied and the viscoelastic responses of emulsions were detected in terms of SNC concentrations (0.2-2.0 wt%) and surface acetylation levels (0.11-0.41° of substitution). The results show that the emulsifying capacity of SNC is improved evidently after surface acetylation due to decreased surface hydrophilicity of SNC and to enhanced electrostatic repulsive effect during emulsification, which is evidenced by the gelation behavior in small amplitude oscillatory shear (SAOS) flow. The modulus and viscosity of the emulsion with acetylated SNC increase by about two orders of magnitude as compared to those of the emulsion with pristine one. The former even shows weak overshoot behavior during large amplitude oscillatory shear (LAOS) flow. This work provides valuable information on motivating development of the Pickering emulsions using SNC as particle emulsifier.

Keywords: Pickering emulsions; Starch nanocrystals; Viscoelasticity.