Gelator-mediated structuring of camellia oil bigels for improved oxidative stability and prediction of lipid oxidation

This study aimed to develop novel bigels as solid fat substitutes and compare the effects of three gelators on their physical properties. Bigels were prepared by mixing whey protein (WPI) hydrogel with glycerol monostearate (GMS), γ-oryzanol/β-sitosterol (SO), and beeswax (BW) based oleogels at different ratios. All bigels exhibited typical hydrogel-in-oleogel (HG/OG) structures as the oleogel content increased from O5:H5 to O8:H2. Among the three systems, GMS-based bigels showed better thermal stability, rheological properties, oil-binding capacity (>97%), and freeze–thaw stability. Their improved oxidative stability was related to the formation of a dense crystalline network, which reduced oil mobility, limited water migration, and slowed oxygen diffusion. In addition, the SVR model showed better prediction performance for POV and TBARS than the PLSR model, with R 2 values above 0.95 and prediction errors below 10%. These findings offer critical structural insights into how different gelators modulate bigels properties, offering the way for the design of healthier solid fat substitutes.