Physicochemical studies of taro starch chemically modified by acetylation, phosphorylation, and succinylation†

Modified starches are some of the mostly used ingredients in the food industry as flavor encapsulants or carrier materials. Therefore, the aim of this research has been to determine the physicochemical characteristics of taro modified starches. Taro starch was used to obtain modified starches such as: succinylated, phosphorylated and acetylated. Measurement of the native starch composition: 15.3% amylose, 92.3% total starch, 3.0 % protein and 5.0 % moisture. The morphology of taro starch granule and the changes undergone by the different chemical modifications were determined by scanning electron microscopy (SEM). The degree of substitution (DS) of the modified starches was found, and such results were complemented with the ones obtained using the Fourier Transform Infrared Spectroscopy (FTIR) to demonstrate that the three different modifications took place, replacing hydroxyl groups with ester groups. It was also possible to determine whether the starches underwent a high or low degree of substitution. Pasting profiles were made using the RVA and differential scanning calorimetric (DSC) was used to study the thermal changes due to the modification process. It was possible to determine that the chemical modifications made to taro starch produced important changes in the physicochemical properties mainly in the starch structure.