Rice bran wax-based oleogels as fat alternatives in vegan emulsion type sausages

This study examined the capabilities of wax-based oleogels as fat substitutes in vegan emulsion-type sausages. Current substitutes like margarine or liquid oils pose challenges in achieving desired textural properties. Wax-based oleogels, with their 3-dimensional crystalline network, offer promising solutions for improving functional and sensory properties of vegan sausages. This research further explored the structure, crystallization behavior, and practical application of wax-based oleogels in food formulations. Rapeseed oil oleogels with varying concentrations of rice bran wax (2%, 4%, 6%, and 8% w/w) were evaluated and used as a complete replacement for traditional fats in vegan Lyoner-style sausages and compared with other sausage samples prepared with rapeseed oil, margarine, or lard. Oleogels were characterized by rheology and differential scanning calorimetry (DSC) to examine macroscopic deformation and thermal behavior. Light microscopy and confocal laser scanning microscopy (CLSM) was employed to analyze the crystalline network in both the wax-based oleogels and the vegan emulsion-type sausages. Oleogels were incorporated into food formulations in a liquid as well as a solid state. Texture profile analysis (TPA) was conducted to assess the hardness. It was revealed that the oleogels formed a uniform crystalline network in the vegan sausages but showed partial structural loss during processing. Sausages made with wax-based oleogels had lower hardness (2%: 325±51 N, 4%: 342±15 N, 6%: 346±15 N, 8%: 339±43 N)  compared to those with margarine (410±32 N) or lard (414±25 N) and were comparable to those with liquid oils (335±20 N). Thermal analyses showed oleogel melting points (63.9 – 70.4 °C) below the sausage cooking temperature, indicating challenges in crystallization control.