Impact of interactions between peanut protein isolate and cellulose nanocrystals on the properties of Pickering emulsions: Rheological properties and physical stabilities

Abstract

The interactions between cellulose nanocrystals and proteins can regulate the interfacial properties of Pickering emulsions, which plays a leading role in the stabilities of Pickering emulsions. In this work, oil-in-water (O/W) Pickering emulsions with different oil-water ratios were prepared using peanut protein isolate modified by cellulose nanocrystals (PPI/CL-CNCs). The distributions of PPI/CL-CNCs at the oil-water interfaces and the microstructures of Pickering emulsions were observed by CLSM and cryo-SEM. The results showed that stable complexes PPI/CL-CNCs formed thick and dense interface layers on the surface of oil droplets. The results of rheological tests clarified that the Pickering emulsions showed an elastic and gel texture, and their gel strength could be enhanced by regulating the oil-water ratios from 3:7 to 7:3. In addition, after one month of storage, the EI of all emulsions remained above 92 % with no obvious phase separation or demulsification. These results suggested that the PPI/CL-CNCs-stabilized Pickering emulsions showed good physical stabilities. The study on the rheological properties and physical stabilities of PPI/CL-CNCs-based Pickering emulsions provided novel insights on developing highly stable Pickering emulsions.