Comprehensive evaluation of saturated monoglycerides for the forming of oleogels

Abstract

To investigate the effect of monoglyceride (MGs) acyl chain length and compounding of MGs on the oleogel properties and stability, 3 different pure MGs and 7 mixtures with different glycerol monostearate (MS): glycerol monobehenate (MB) ratios were studied with high oleic sunflower oil (HOSO) as the liquid oil. The oleogel properties were characterized in terms of structuring potential including oil binding capacity (OBC), hardness and rheological behavior, and the microstructural features associated with these properties determined by differential scanning calorimetry (DSC), solid fat content (SFC), X-ray diffractometry (XRD) and polarized light microscopy (PLM). Changes in oleogel properties (OBC and hardness) and the microstructure during 30 days of storage were also evaluated. Different chain lengths and ratios of MS:MB led to different crystallization rates, polymorphic transitions and aggregation rates, so as to form different crystalline networks and stabilities. In general, the MB oleogel exhibited the highest properties and stability. An increase in OBC in the order of glycerol monolaurate (ML) < MS < MB was observed for pure MG oleogels. The oleogels with mixed MGs outperformed the mechanical properties of the single ones. The best oleogel properties and stabilities were obtained for the oleogel with the MS:MB ratio as 2:8.