Chemical and Functional Properties of Food Saccharides

© 2004 by CRC Press LLC
TABLE 22.2
Experimental Approaches to Obtain Molecular and Supramolecular
Characteristics of Starch Polysaccharides
Experimental Approach Information
Thin layer chromatography (TLC)
Enzymatic assays
Reversed phase high performance liquid
chromatography (rpHPLC)
High performance anion-exchange
chromatography – pulsed amperometric
detection (HPAEC-PAD)
Enzymatically controlled step-by-step
fragmentation + fragment analysis by rpHPLC
or size-exclusion chromatography (SEC)
Semipreparative SEC: staining and complexing
+ spectroscopy
Identification and quantification of soluble
components, monosaccharides, disaccharides,
oligosaccharides obtained from direct
extraction or enzymatic and acidic hydrolysis
Branching characteristics: chain-lengths
distribution, branching percentage
Mass fractions separated according excluded
volume for subsequent processing or analysis;
fraction-specific branching characteristics;
SEC: mass + standards Calibrated molecular weight distribution, degree
of polymerization distribution, molecular
weight averages
Absolute molecular weight distribution, absolute
degree of polymerization distribution, excluded
SEC: mass, light scattering, and viscosity
volume distribution, polysaccharide-coil
packing density distribution
Quantitative terminal labeling of polysaccharides
+ SEC: mass/molar
Absolute molecular weight distribution of molar
fractions
Intrinsic viscosity Excluded volume, overlapping concentration
Viscosity at varying shear stress Viscous + elastic contributions (visoelasticity);
gel properties
Viscosity at increasing thermal stress Gelatinization temperature (range);
disintegration temperature (range)
Viscosity at varying thermal + constant
mechanical stress (Brabender viscograph)
Stability or resistance toward applied energy
(temperature, shearing, periods); disintegration
or reorganization capacities
Differential scanning calorimetry (DSC) Modifications in conformation; phase transitions
Photon correlation spectroscopy (PCL) Diffusion mobility of molecular and
supermolecular polysaccharide structures
of the appropriate sequences of preparation and analyses for starch-containing crop
materials: sampling at the location of harvesting followed by comprehensive and
time-consuming fractional preparations and analyses. In case of particular interest
in individual parameters or a limited parameter group only, this scheme may be
simplified; however, comprehensive information requires the full set.