Oleogels from sodium stearoyl lactylate-based lamellar crystals: Structural characterization and bread application.

Sodium stearoyl lactylate (SSL) was used as a gelling agent to structure oleogels at concentrations of 7%, 9%, 11%, and 13% (w/w) with sunflower oils in this study, respectively. The physical characteristics of oleogels, such as solid fat content (SFC), oil bonding capability (OBC) and firmness, were influenced by SSL crystals. Therefore, the microstructure and interaction of oleogels was further investigated by polarizing light microscopy (PLM), X-ray diffraction (XRD), rheology, differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). It was found that the higher concentration of oleogelator resulted in a denser crystalline network, which provided stronger mechanical strength and enhanced the ability to retain the oil phase. Space-spanning networks were attributed to surface interactions among crystals of SSL, such as van der Waals interactions and electrostatic repulsion. Crystal network in the SSL oleogels imitated the typical functionality of crystalline network structures formed by triacylglycerol.