Characterization and Mechanisms of Novel Emulsions and Nanoemulsion Gels Stabilized by Edible Cyclodextrin-Based Metal–Organic Frameworks and Glycyrrhizic Acid

In this study, a novel emulsion stabilized by nano-cyclodextrin-based metal-organic frameworks and glycyrrhizic acid (CD-MOF/GA) was successfully fabricated, exhibiting long-term storage stability. The characterization and mechanisms for the emulsion formation with CD-MOF/GA were studied. The phase change of the emulsions from sol to gel could be controlled using different oil fractions and mass ratios of CD-MOF and GA. The rheological results showed that the emulsions were transformed from liquid emulsions to emulsion gels when the oil fractions were higher than 0.3 and the mass ratio of CD-MOF and GA was 1:3. The low-field nuclear magnetic resonance results revealed that the T22 relaxation time of emulsions decreased from 403.702 to 231.013 ms when the oil fractions increased from 0.1 to 0.6, indicating that movable water was converted to constructal water. The emulsions showed good stability, even in high-alkaline pH and high-temperature conditions.