Investigating the impact of beeswax addition and diacylglycerol profiles on bigel properties and application in bread: Insights on intermolecular interaction mechanisms

This study investigates the development of diacylglycerol (DAG)-based bigels as a healthier substitute for baking oil by combining hydroxypropyl methyl cellulose (HPMC)-based hydrogel with beeswax (BW)-based oleogel. Results indicated that increasing the concentration of BW enhances the interpenetration ability between the oleogel and hydrogel, leading to the formation of a stable bi-continuous bigel, as well as improved gel properties and thermal stability. The lipid profiles revealed that DAG's fatty acid composition could result in higher viscosity (0.07 ± 0.00 Pa.s) and lower interfacial equilibrium ability (14.02 ± 0.23 mN/m) compared to triglycerides (TAG). These characteristics contributed to enhanced mechanical properties and the maintenance of oil-water interface stability in the bigel. Spectroscopy and molecular dynamics simulations demonstrated that the DAG-based bigel could exhibit stronger van der Waals forces and hydrogen bonding between molecules compared to the TAG-based bigel. Consequently, DAG-based bigels showed superior gel properties and stability. Furthermore, textural analyses and sensory evaluations indicated that replacing 50% of butter with the DAG-based bigel in bread does not significantly alter the product compared to using 100% butter. This study underscores the potential of DAG in the preparation of bigels, promoting their application as the fat substitutes.