Study on the coupling progress of thermo-induced anthocyanins degradation and polysaccharides gelation

Sensitivities of anthocyanins to pH and thermal treatment greatly limit their applications in food as the functional ingredients or natural pigments. Here, synergistic hydrogels formed by mixing konjac glucomannan (KGM) and xanthan gum (XG) were utilized to enhance the thermal stability of anthocyanins at various pH values (3.0, 6.0, and 9.0). Gels network was studied by combining the bulk-rheology and micro-rheology measurements. Interestingly, the thermo-induced anthocyanins degradation and the reconstructing of gel networks occurred simultaneously in KGM/XG hydrogels. Results showed that the gelling behavior of KGM/XG protected anthocyanins from thermo-exposure. That provides a promising strategy for stabilizing thermo-sensitive bioactive compounds in the thermo-induced gelling systems.