Konjac Glucomannan Acts as the Skeleton of Emulsion Gel Exhibiting Stable Water Retention by Promoting the Structure Density of Gel Network

Konjac glucomannan (KGM) exhibits superior water absorption, gelation, and emulsification properties, as well as health benefits due to its indigestible fiber content. This study aims to dig into the skeleton role of KGM (0.3–1.5%) on structure formation, water retention, and stability of emulsion gel constructed with pea protein isolate-octenyl succinic anhydrate corn starch (PPI/OSA-CS) composite. Emulsion gels containing increased KGM exhibited densification in the gel network, and 1.2–1.5% KGM showed ideal network structure without voids. Besides, emulsion gels containing 1.5% KGM showed the highest viscosity and viscoelasticity (e.g., elastic modulus 945 Pa compared to the control group (0.2 Pa) within the linear viscoelastic region (LVR)), indicating the formation of a stable protein network. The water retention, freeze-thaw stability, and thermal stability of the emulsion gel were also improved. The findings provide insights into the use of KGM to keep activity of the biological molecules in the emulsion gel as potential animal fat simulators.