Construction of soybean oil bodies–xanthan gum composite oleogels by emulsion-templated method: Preparation, characterization, and stability analysis

Abstract

Oil bodies (OBs), a special tissue that stores oil in plant cells, are rich in polyunsaturated fatty acid, vitamin E, phytosterols, and other functional components. In this study, different concentrations of xanthan gum (XG)-stabilized OBs were prepared using the electrostatic deposition technique, and oleogels were prepared via freeze-drying and shearing effects. The relationships between the properties of OB emulsions (OBEs), intermediate products (freeze-dried samples), and end products (oleogels) were explored. The XG addition significantly enhanced the stability of OBs. Particularly, when it achieved 1.5%, the average particle size of OBEs was the least at 892.03 nm, the ζ-potential absolute value was greater than 30 mV, and the porosity was a minimum of approximately 3.68%. Freeze-dried samples with XG had less oil on their surfaces, and their hardness and springiness were significantly and positively correlated with XG addition. The excellent stability of the OBEs and freeze-dried samples resulted in the formation of a dense and stable three-dimensional network structure to hold the oil. The oil holding capacity, rheological properties (including higher yield stress, stronger elastic, and thixotropy behavior), and thermal stability of the oleogels improved with increasing XG addition. Moreover, the compact networks and excellent oil holding capacity of the OB-based oleogels with XG effectively hindered high-temperature destruction and oil oxidation. The correlation analysis and the scheme model indicated that the oleogel properties could be traced back to the interaction effects among the OB components. These results provide guidance for the design and quality control of OB-based oleogels.