Gel properties and interactions of hydrogels constructed with low acyl gellan gum and puerarin

To develop composite hydrogels based on low acyl gellan gum (GG), the effect of puerarin (PUE) on the gel properties of GG was investigated. The results showed that the maximum storage modulus (G ') of the 1.2 % GG/ 0.8 % PUE composite hydrogel was 377.4 Pa at 0.1 Hz, which was enhanced by 4.7-fold compared with that of 1.2 % GG. The melting temperature of this composite hydrogel increased from 74.1 degrees C to >80.0 degrees C. LF-NMR results showed that a significant amount of free water was present in the hydrogel matrix. The surface struc-ture aggregation and the shrinkage of the honeycomb meshes in the composite hydrogel proved the cross-linking of PUE and GG. XRD, FTIR and molecular simulation results illustrated that hydrogen bonds were the most important factor controlling the interaction between GG and PUE. Thus, the GG/PUE composite hydrogel has good elasticity, thermal stability and water retention, which lays a good foundation for further application in the food industry.

Automated summary

The effects of puerarin on the gel properties of gellan gum were investigated, and it was found that puerarin enhanced the storage modulus and thermal stability of the composite hydrogel. The interactions between puerarin and gellan gum were controlled by hydrogen bonds. The study suggests that the GG/PUE composite hydrogel has potential applications in the food industry.