Preparation of Potato Starch Nanoparticles Using Acid Hydrolysis and Ultrasonic Post-treatment
Kamal Narayan Baruah, Siddhartha Singha, Ramagopal V.S. Uppaluri
Abstract
Novel starch nanoparticles being prepared with a combination of acid hydrolysis-sonication have been characterized and compared with those prepared with the conventional acid hydrolysis method. The experimental investigations considered variations in sulfuric acid molar concentration (3.16–5 M) and hydrolysis duration (24–72 h) to achieve reduced fabrication time (24–48 h) in conjunction with 7–9 days of conventional hydrolysis and enhanced nanoparticle properties that are compatible with carapace encapsulation materials. It was interesting to observe that the pulse mode of sonication facilitated better formation of starch nanoparticles with lower combinations of average particle size (50–160 nm) and polydispersity index (0.2–0.7) in comparison with and without sonication assisted acid hydrolysis methods. Also, the relative crystallinity and melting point was enhanced with increasing sulfuric acid concentration. XRD studies indicated that a change in the structure of the starch granule and possible rearrangements during retrogradation led to a change in the crystalline structure of the nanoparticles compared to that of native starch.