The demand for healthier chocolate spreads has encouraged the development of fat-structuring systems that mimic cocoa butter while reducing saturated fatty acids (SFA). This study developed bigels composed of palm kernel stearin (PKS)-structured canola oil (oleogel phase) and either sodium alginate (ALG) or Alyssum homolocarpum seed gum (AHSG) (hydrogel phase) for chocolate spread applications. The effects of oleogel:hydrogel ratio (30:70–50:50), hydrogelator type and concentration (1.5–2.5 g/100 g), and PKS content (20–50 g/100 g) were evaluated in terms of textural, rheological, thermal, and microstructural properties. Increasing oleogel fraction and PKS content enhanced hardness, viscosity, and elastic behavior, with ALG-based bigels forming stronger networks than AHSG systems. Microstructural analysis revealed more homogeneous crystalline networks at higher oleogel levels, predominantly in the desirable β′ polymorphic form associated with smooth texture and stability. FTIR results confirmed physical compatibility without chemical interactions between phases. All bigels exhibited good stability under freeze–thaw and inversion conditions. When incorporated into chocolate spreads, bigel with a 50:50 oleogel to hydrogel ratio achieved sensory properties comparable to a commercial product and outperformed oleogel-only samples. Importantly, SFA content was reduced by approximately 56%, highlighting the potential of bigels as healthier fat alternatives in chocolate spreads. • Bigels combining oleogel and hydrogel networks were optimized as fat replacers for chocolate spreads. • Oleogel fraction and palm kernel stearin content governed bigel rheology, texture, and elasticity. • Alginate-based bigels formed stronger, more cohesive networks than AHSG-based systems • Bigel-based chocolate spreads matched commercial products in sensory acceptance and stability. • Saturated fatty acid content was reduced by approximately 56% using bigel structuring.
Ebrahimi et al. (2026) studied this question.