Ultrasound-assisted dissolution and characterization of maize starch using asymmetrical flow field-flow fractionation coupled with multiple detectors

Abstract

A molecularly dispersed solution is a prerequisite for the reliable molecular characterization of starch. In this study, an ultrasound treatment was employed to facilitate complete dissolution of maize starch in dimethyl sulfoxide (DMSO). The effect of ultrasound time and amount of DMSO on the dissolution of maize starch was studied. The ultrasound-assisted DMSO dissolution method for the maize starch was evaluated by differential scanning calorimetry (DSC) and asymmetrical flow field-flow fractionation (AF4). Moreover, the molar mass and size distributions, and the apparent density of the maize starch sample were characterized by AF4 coupled with multi-angle light scattering (MALS) and differential refractive index (dRI) detectors (AF4-MALS-dRI). The reproducibility of the ultrasound-assisted DMSO dissolution method for AF4-MALS-dRI analysis of maize starch was investigated. Results reveal that maize starch can be completely dissolved in a shortened processing time by the ultrasound-assisted DMSO method, which makes AF4-MALS-dRI data more reliable. Novelty statementAn ultrasound-assisted DMSO method for dissolution of maize starch was developed. Results reveal that maize starch can be completely dissolved in a shortened processing time by ultrasound-assisted DMSO method, which makes AF4-MALS-dRI data in terms of Rg and Mw more reliable.