Determination of molecular mass distribution of amylopectin using asymmetrical flow field-flow fractionation

Treatment of wx corn starch dispersions in a microwave reactor and their hydrodynamic properties determined using asymmetrical flow field‐flow fractionation

“…1) which relates to the sphere‐equivalent hydrodynamic radius ( R h ) (Eq. 2) 5–7, 10. where t 0 is the void time, F cr the cross flow rate, w the channel thickness, V 0 the geometric void volume, t r the detected retention time, k B the Boltzmann's constant, T the absolute temperature and η is the viscosity coefficient of the solvent.…”

“…The reliable determination of the de‐facto molecular characteristics requires complete dissolution of starch–glucan materials 1–7. A detailed literature survey on the influence of various dissolution protocols and analytical techniques upon molar masses, radii of gyration and hydrodynamic radii ( R h ) values for wx corn starch (99% AMP) has been previously published 7. An overview of the literature R h values for wx corn starch using various dissolution protocols and determined using numerous analytical techniques is given in Table 1.…”

“…Aggregation of the starch–glucan molecules in aqueous media is a dynamic process and is highly influenced by the inherent nature of the sample and the dissolution procedures employed 1–7. Furthermore, it is difficult to ascertain the degree of aggregation of starch solutions and dispersions.…”

“…Dissolution procedures employing a high pressure microwave vessel treatment (HPMV) 3–9 are rapid in comparison to other dissolution procedures such as autoclaving 10, 11 alkali/acid treatments 12 or use of organic solvents (particularly, DMSO) 12, 13 (Table 1). Some dissolution processes, such as HPMV, require a pre‐gelatinisation step to aid the disruption of the starch granules and improves the dispersion of the starch materials in aqueous media 3–9, 14 as shown in Table 1. However, domestic microwave instruments lack the ability to control and monitor the processing temperature inside the vessel.…”

Separation and characterization of food macromolecules using field-flow fractionation: A review

“…The results from the AF4-MALS analyses were compared to capillary viscometry and increases in apparent densities were reflected in increases in the overlap concentration, c*. Recently, several papers with results for various starches utilizing AF4 have been reported (Juna & Huber, 2012a, 2012b, 2012cJuna, Williams, & Davies, 2011;Perez et al, 2011) including an extensive study of natural starches (Wahlund, Leeman, & Santacruz, 2011) and a comparison between AF4 and hydrodynamic/size exclusion chromatography (HDC-SEC) (Rolland-Sabaté et al, 2011).…”