Physicochemical properties of oleogels based on sunflower or soybean oil structured with rice bran wax

Growing consumer awareness of the adverse health impacts of trans and saturated fats has increased the demand for healthier lipid alternatives. Oleogels represent a promising alternative to hydrogenated fats, consisting of a liquid oil phase immobilized within a three-dimensional crystalline network formed by low-molecular weight gelators. This study aimed to produce oleogels based on sunflower oil (SFO) and soybean oil (SBO) as the lipid matrix, structured using rice bran wax (RBW) at concentrations of 2.5g/100 g and 5g/100 g. RBW was selected for its high ester content, moderate melting point, and natural origin as a sustainable by-product of rice bran oil refining. Gas chromatography and HPLC were used to analyze fatty acid and triacylglycerol profiles, while DSC was employed to examine thermal properties. The fatty acid composition of SFO (ΣPUFA/ΣSFA = 4.31) and SBO (ΣPUFA/ΣSFA = 2.84) influenced the crystallization and thermal transitions of the resulting oleogels. Melting temperatures followed the order: 2.5 g/100 g RBW/SBO <2.5 g/100 g RBW/SFO <5 g/100 g RBW/SBO <5 g/100 g RBW/SFO. Increasing RBW concentration enhanced firmness and structural consistency, confirming stronger crystalline network formation. These findings demonstrate that both oleogelator concentration and oil matrix composition govern oleogel stability and textural performance. The results highlight the potential of RBW as a clean-label, plant-based structuring agent for developing trans-fat-free fat systems suitable for food applications.