Chemical and Functional Properties of Food Saccharides

© 2004 by CRC Press LLC
TABLE 22.3
Branching Characteristics of a Wheat Starch Polysaccharide from
Destructive Step-by-Step Fragmentation and Subsequent Fragment
Analysis
% DP n Seg Glc n Full turns Br %
Waxy Maize
Molecule 940 960 5.3
C-chains 5 50 1 50 1 × 2–7
B-chains 23 50 4 200 4 × 7
A-chains 72 15 46 690 58 × 2
A- + B-chains 95
Wheat: Initially n-BuOH Precipitated Fraction (22%)
Molecule 255 255 3.6
C-chains 46 112 1 112 1 × 2–15
B-chains 14 39 1 39 1 × 6
A-chains 40 13 8 104 8 × 2
A- + B-chains 54
Wheat: Subsequent MeOH Precipitation from Supernatant (78%)
Molecule 966 966 6.3
C-chains 5 50 1 50 1 × 2-7
B-chains 25 40 6 240 40 × 7
A-chains 70 13 52 676 52 × 2
A- + B-chains 95
Note: %: percentage; DPn: number average degree of polymerization; Glcn: number of anhydro
glucose units; seg: number of segments (branches); full turns: number of helical full turns for
complexation; br %: percent branching.
kind of information as the SEC concept, in particular SEC combined with multiple
detection, provides comprehensive information about molecular and supermolecular
dimensions, molecular conformations, and interactive potentials of separated polymers
and oligomers.
Simplified, the filling of volume (V e; Equation 22.1a) by starch polysaccharides
is controlled by a fine-tuning mechanism at the molecular level, which modifies
polymer/oligomer domains due to changing external and internal conditions. At least
three major controlling classes of how volume (V e) is structurized can be distinguished:
Conformation (mc; Equation 22.1a): Molecular symmetries in terms of
helices, branching pattern (short-chain, long-chain branches, number of