Gelation behavior and crystal network of natural waxes and corresponding binary blends in high-oleic sunflower oil.

Abstract

Wax-based oleogels attract considerable attention for their perfect gelation properties, but the waxy mouthfeel severely limits their implementation in food. Herein, we developed a novel strategy via designing the crystal network to produce wax-based oleogels with a suitable mouthfeel. Four natural waxes with different melting points were selected as oleogelators to investigate the gelation behavior. All waxes at 5 wt% concentrations could form stable oleogels with low-frequency dependence. Especially, rice bran wax (RBW) and beeswax (BW) with high oil-binding capacity indicated that the ordered crystal network with fiber or needle-like morphology is more suitable for trapping liquid oil. Interestingly, China lacquer wax (ZLW) presented satisfactory oral melting characteristics according to the melting properties. Subsequently, to enhance the structure of ZLW-oleogel, RBW and BW with desirable crystal networks were added at varying mass ratios (100:0, 75:25, 50:50, 25:75, and 0:100). The binary oleogels exhibited monotectic behavior from thermodynamic phase diagrams. The polarization microscope indicated that similar needle-like crystals in BW/ZLW system enhanced the order of network structure, while long fiber-like crystals by RBW dominated the crystallization of RBW/ZLW binary oleogels. Finally, the BW/ZLW binary oleogels with ratios of 25:75 and 50:50 showed no-waxy mouthfeels in sensory analysis. These findings provide strong theoretical support for the application of wax-based oleogels in plastic fats replacement. PRACTICAL APPLICATION: Natural wax-based oleogel has been widely investigated due to the high oil binding capacity and perfect gelation properties. But its waxy mouthfeel severely limits the application in the food industry. In this study, oleogels with no-waxy an mouthfeel were obtained by designing wax-blend crystalline network. These findings provide strong theoretical support for the application of wax-based oleogels in plastic fats replacement.