Preparation of high-strength elastic bigel with dual network structure to stabilize astaxanthin for low-fat food filling

Oil-water bigels stabilized by edible colloidal particles have gained great attention for applications in 3D printing, delivery of both hydrophilic and hydrophobic bioactive compounds, and preparation of low-fat products. In this study, we presented a simple method to prepare oil-water bigels utilizing only gelatin and calcium alginate (CA) complex to stabilize oleogel promoted by glycerol monostearate (GMS). The oil phase (flaxseed oil) was maintained at 20%, enabling the development of low-fat formulations. The superior performance was attributed to the formation of a synergistic gel network through electrostatic interactions and hydrogen bonding between gelatin and CA, which effectively entrapped oil droplets and modulated the release behavior of astaxanthin. Its high stability and encapsulation efficiency make it an effective carrier for functional food ingredients (astaxanthin was selected). When stored at room temperature and 50 degrees C for 14 days, the astaxanthin retention remained above 80% under both conditions. The resulting bigel exhibited shear-thinning behavior, high viscoelasticity, and rheological properties suitable for 3D printing. Based on these properties, a low-fat product of "Light Triangle Sandwich" was proposed. These findings demonstrate a straightforward strategy for producing bigels with enhanced performance, offering promising potential for future functional food applications.