Characterizations of Pickering emulsions stabilized by starch nanoparticles: Influence of starch variety and particle size.

Pickering emulsions were first successfully fabricated by different types and sizes of corn, tapioca, sweet potato, and waxy corn starch nanoparticles as stabilizers. Photography, optical microscopy, confocal laser scanning microscopy, and rheology measurements were used to characterize Pickering emulsions stabilized by various starch nanoparticles. The results showed that tapioca, sweet potato, and corn starch nanoparticles were appropriate for Pickering emulsion stabilization because the three nanoparticles have nearly neutral wettability (θ ∼90°). Confocal microscopy revealed that intact and thick nanoparticle shells coated the surface of oil droplets. The Pickering emulsions stabilized by sweet potato and corn starch nanoparticles with a diameter that ranged from 100 to 220nm had better stability than those with a diameter either less than 100nm or more than 220nm. These results suggested that starch nanoparticles could be used as promising particulate emulsifiers to fulfill the demands of Pickering emulsions with stable characteristics.