Synergistic interactions of ionic/non-ionic polysaccharides in biopolymer-based emulsion gels: Insights into the development of solid fat analogue

Composite emulsion gels exhibit considerable promise for the replacement of block fat analogues with their structural characteristics being tightly associated with the stability mechanism conferred by the incorporated polysaccharides. In the present study, an emulsion-gel system for solid fat analogue was developed using soy protein isolate (SPI) as the structural scaffold. Model systems comprising SPI-KGM, SPI-κ-KC, and SPI-KGM/κ-KC were constructed to elucidate the stabilization mechanisms imparted by non-ionic, ionic and synergistic polysaccharide combinations. SPI could create a continuous gel under the induction of transglutaminase. Polysaccharides induced the formation of SPI network structures. KGM was filled in the protein network and interacted with SPI through hydrogen bonding to form a porous network structure. In contrast, κ-KC at high concentration disrupted the protein network by interacting with SPI through ionic and hydrogen bonding. When the ratio of KGM to κ-KC was 6:4, the interaction between the two polysaccharides reached its maximum, whereas the interaction between the polysaccharides and SPI was attenuated. These findings provide new insights into the design of solid fat analogue.