Impact of gelatin/K-carrageenan ratio in the properties of bigels for food applications

This study aimed to investigate the synergistic effect between gelatin and κ-carrageenan on the structure and properties of bigels. Beeswax was used as the oleogelator, while gelatin and κ-carrageenan served as hydrogelators to prepare oleogels and hydrogels separately. The two gels were subsequently mixed in an ice-water bath to form bigels. By adjusting the ratio of gelatin to κ-carrageenan in the hydrogel phase, the microstructure, freeze–thaw stability, and rheological properties of the resulting bigels were systematically characterized. The results revealed that increasing gelatin content led to a reduction in interfacial tension within the aqueous phase, resulting in finer oil droplet dispersion and a more homogeneous and compact microstructure. The synergistic interaction between gelatin and κ-carrageenan enhanced the stability of the hydrogel network and improved its oil encapsulation capacity, thereby significantly improving the freeze–thaw stability of the bigels. Rheological analysis showed that an appropriate proportion of gelatin notably increased the storage modulus of the bigels, indicating a more robust internal structure. This study provides a novel strategy for the development of high-performance structured lipids for food applications.