Characterisation of normal corn starch using asymmetrical flow field‐flow fractionation

Abstract

Abstract The apparent average molar masses ( M w,app ), apparent average radii of gyration ( R g,app ), diffusion co‐efficients ( D T ), and hydrodynamic radii ( R h ) of normal corn (maize) starch and fractions were determined using asymmetrical flow field‐flow fractionation coupled with multi‐angle light scattering and refractive index detectors (AF4/MALS/RI). AM‐type (Fraction A) and AP‐type (Fraction B) were chemically separated from normal corn starch. Normal corn starch and Fractions (A–B) were dissolved in 1 M KSCN using a high pressure microwave vessel. The effect of varying cross flow rates at a fixed channel flow rate upon the M w,app and R g,app distributions of normal corn starch and Fractions (A–B) were investigated. The average M w,app of normal corn starch, Fractions (A) and Fraction (B) were 41 × 10 6 , 1.4 × 10 6 and 39 × 10 6 g/mol, respectively, with R g,app values of 129, 60 and 129 nm, respectively.