This study aimed to develop novel bigel system utilizing a combination of guar gum (GG) as the hydrogel phase and rice bran wax (RBW)/walnut oil (WO) as the oleogel phase to mimic the characteristics of solid fats. The oleogel was prepared using RBW as the oleogelator concentrations of 8 and 9% mixed with the hydrogel phase at different ratios (30:70, 50:50, and 70:30) through defined mixing speeds (600 and 1800 rpm) to produce an emulsifier-free bigel. The effects of RBW (as oleogelator) concentration, oleogel/hydrogel ratio, and mixing speed were investigated on the microstructure, oil binding capacity, rheological properties and textural properties of bigel samples. Based on the results the highest hardness (1.84 N), spreadability (4.45 N.mm), and firmness (2.23 N) were observed in the sample prepared with 9% RBW. Increasing the mixing speed resulted in decreased adhesiveness and increased oil binding capacity. The highest adhesiveness (2.33 N.mm) and oil binding capacity (100%) were observed in the bigel containing 9% RBW and 30% oleogel. According to the obtained results the bigel prepared using 9% oleogelator and 30:70 ratio of oleogel/hydrogel at 600 rpm mixing speed demonstrated better physicochemical properties and could be recommended for food applications as a fat replacer.

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