Methodologies for symmetrical-flow field-flow fractionation analysis of polymeric glutenin

Abstract

Symmetrical-flow field-flow fractionation analysis was used to estimate the molecular size distribution (MSD) of glutenin from Australian wheat cultivars. The high molecular weight end of the MSD is important for predicting dough quality, but is difficult to measure by most characterization methods. Two parameters were considered to quantify the high molecular part of the distribution. A measure of the ratio of the rates of chain extension and termination, Λ, was adopted from methods introduced for synthetic polymers. The molecular weight below which 99% of total signal intensity should be observed, A99, was also estimated. It was hypothesized that Λ would not be sensitive to extraction conditions, but it was found to be dependent on the sonication time used in isolation of the glutenin. Λ and A99 showed strong positive correlations with mixing time and maximum resistance to extension, parameters related to dough quality.