Soy protein isolate-acylated anthocyanins self-assembled nanoparticles enhanced bigels physicochemical properties: Effect of amphiphilic nanoparticles on the bigels system

The amphiphilic nanoparticles prepared from soy protein isolate and acylated anthocyanins based on the Mannich reaction were innovatively incorporated into bigels. The bigels were prepared by beeswax oleogels and guar gum hydrogels, with systematic investigation of nanoparticles on the physical properties and stability. The results showed that the bigels belonged to hydrogels-in-organogels type, and the addition of amphiphilic nanoparticles acheived the dual effect of interfacial and morphological stability of the bigels. FTIR spectra revealed that nanoparticles enhanced the hydrogen bonding and hydrophobic interaction in the bigels network structure. The rheological behavior of the bigels was affected by the change of structure. The bigels with nanoparticles had higher storage modulus and faster creep recovery rate. Textural analysis also indicated that the hardness increased from 341.553 to 564.444 N when the content of nanoparticles in the bigels was 1.0 wt% (BG-10), implying that the nanoparticles conferred stronger mechanical properties of the bigels. In addition, BG-10 exhibited the highest oil binding capacity (95.5 %), the lowest peroxide value (0.44 meq/kg), and the lowest malondialdehyde content (0.061 mg/kg) on the 28th day of storage. Nanoparticles-incorporated bigels were characterized by high mechanical strength, excellent creep recovery ability, and enhanced storage stability, positioning them as promising fat substitutes for developing customizable low-fat functional foods.