Preparation and Characterization of Nanoparticles From Lotus Root Starches by Ultrasonic‐Assisted Nanoprecipitation

ABSTRACT Lotus root starch nanoparticles (LRSNPs) were prepared by an ultrasonic‐assisted nanoprecipitation method, and their structure and physicochemical properties were characterized. The optimal preparation process for LRSNPs was predicted through single‐factor experiments and response surface methodology as follows: an ultrasonic power of 500 W, an ethanol/starch solution volume ratio of 10:1, and a starch solution concentration of 3%. The particle size of LRSNPs prepared under these conditions was 215.92 nm, which was smaller than that obtained by both nanoprecipitation and enzymatic hydrolysis regeneration methods. After ultrasonic nanomaterialization, the structure of lotus root starch (LRS) was disrupted, the short‐range ordering was reduced, and the crystal structure changed from B‐type to V‐type. Compared with corn starch nanoparticles (CSNPs) and potato starch nanoparticles (PSNPs), LRSNPs exhibited higher solubility and swelling capacity at 50–60°C, and its transparency was significantly enhanced. Moreover, LRSNPs had a faster digestion rate in a simulated intestinal environment, and their rapidly digestible starch content was significantly higher than that of CSNPs and PSNPs. This study provided a theoretical basis for the further development and utilization of LRS.