Improvement of Lactiplantibacillus plantarum stability and quality of 3D-printed brown rice by chickpea protein and fenugreek gum stabilized Pickering emulsions

The effect of Pickering emulsions (PEs) stabilized with chickpea protein (CP) and fenugreek gum (FG) on the stability of Lactiplantibacillus plantarum (L. plantarum) and improvement of the quality of 3D printed brown rice were investigated. The PEs were prepared by CP and different FG concentrations (0.2 %, 0.5 %, 0.8 %). As the addition of FG increased from 0.2 % to 0.8 %, the D[4,3] decreased from 26.75 μm to 12.55 μm, and the zeta potential decreased from −32.34 ± 2.47 mV to −33.82 ± 0.90 mV. The system stability was improved. The probiotic survival was examined during various storage time (0–8 d), heat treatment (65 °C, 72 °C), in vitro simulated digestion, and 3D printing process (temperature, infill density, extrusion multiplier). And the emulsification effects on rheological, textural, and swallowing properties of 3D printed brown rice ink were assessed. The results showed that, under heat treatment at 72 °C, PE-0.8 % increased the survival rate of L. plantarum, with a 1.39 log CFU/g higher survival compared to the control group. Additionally, during the gastric digestion stage, the survival rate of L. plantarum in the PE-0.8 % group was 2.70 log CFU/g higher than that in the control group, indicating that PE-0.8 % provided strong protection for L. plantarum under both high temperature and acidic conditions. Brown rice inks exhibited shear-thinning properties, where FG formed a dense network structure through moisture competition, ensuring easy swallowability while preserving print support. This study demonstrated the dual functionality of PEs in both probiotic protection and enhancing 3D food printing. It emphasized the potential value of PEs for applications in the food industry and offered new strategies for developing functional foods suitable for elderly people.