Effect of acid and hydrolysis duration on the characteristics of arrowroot and taro starch nanoparticles

Abstract

Arrowroot and taro are underutilized tuber. Modification of starch into starch nanoparticles will open to opportunities for further development. The aim of this research was to find out the influence of acid types and hydrolysis length on the characteristics of the resulted starch nanoparticle. There were group of treatments including source of starch: Arrowroot and taro beneng starch, and the acid types was HCland H2SO4, and the length of hydrolysis was 3 and 5 hours. The results showed that the yield of arrowroot nanoparticle starch was higher than taro, 21.64-34.44% and 33.83-51.22%, respectively. Hydrolysis with HCl and H2SO4 produced starch nanoparticles (NP) with different characteristics. Treatment with HCl provides higher yield than that of H2SO4, but particle size was larger. The average size of the taro and arrowroot starch nanoparticles produced by hydrolysis by H2SO4 was 379.2 nm and 464.4 nm, respectively, with high polydispersity index of 0.480 and 0.621. Meanwhile, the crystallinity of taro and arrowroot starch NP increased from 44.1 into 87.3% and 43.5% into 51.3%, respectively. Acid hydrolysis improved solubility of starch nanoparticles but decreased the swelling power and gelatinization temperature. Starch nanoparticles can be implemented as a reinforcing agent for packaging, and carrier material for phytochemicals or agro-chemicals.