Natural surfactants with remarkable interfacial properties like saponins are particularly attractive in fabricating multiphase food systems. Glycyrrhizic acid (GA), a food-grade saponin, has a supramolecular self-assembly behavior in water and can form ultrafine semiflexible nanofibrils with excellent gelation ability and interfacial activity. The controllable assembly of GA nanofibrils at the liquid interfaces and in the continuous phase makes them highly suitable as building blocks for preparing multiphase colloidal systems with high stability, stimulability, and processability. Herein, we mainly introduce the chiral amphiphilic structure of GA molecules and their fibrillar self-assembly in aqueous solutions, as well as the behavior of GA nanofibrils at the interfaces. The recent novel applications of GA and GA nanofibrils in various multiphase food systems are discussed.