Characterization of olive oil emulsions stabilized by flaxseed gum

Abstract

In this study, the stability and properties of oil-in-water emulsion stabilized by different flaxseed gum (FG) concentrations (0.1%–0.5%, w/w) are investigated. The mean droplet diameter, microstructure, rheological properties, and creaming stability are evaluated. High-field nuclear magnetic resonance spectroscopy (HF NMR) was used for emulsions with 10-wt% olive oil. It can be observed that the emulsions stabilized by concentrated FG exhibits a smaller droplet size. Although the emulsions with high FG concentrations (0.3%–0.5%, w/w) have occurred depletion flocculation, the emulsions still display a better creaming stability, which can be attributed to the rheological properties. The storage modulus (Gʹ) and loss modulus (Gʹʹ) are observed to increase with the increase in the FG concentrations. Furthermore, Gʹ and Gʹʹ of the emulsions containing 0.4%–0.5% (w/w) FG depicts better rheological properties. The HF NMR spectra exhibits an increased line-width with an increased FG concentration, which confirms that there is a strong interaction between the FG and oil molecules. This study supports the application of FG in the food industry and provides a theoretical basis for the application of NMR technology to the vegetable oil emulsion system.