Chemical and Functional Properties of Food Saccharides

© 2004 by CRC Press LLC
lg(M) [g/mol]
Mass Fraction
0.8
0.6
0.4
0.2
0
8
7
6
5
4
3
30 36 42 48 54
Vret
[mL]
(a)
4.5 5 5.5 6 6.5 7 7.5 8 8.5
lg(M) [g/M]
(b)
FIGURE 22.7 (a) Molecular weight calibration for SEC-separated starch glucans: absolute
molecular weight calibration from mass/LS data (Equation 22.2a) for waxy maize (⎯ ⎯)
and wheat (⎯0⎯); universal calibration diminished for viscosity contributions (Equation
22.2i and Equation 22.2e) for waxy maize (⎯⎯) and wheat (⎯⎯). (b) Molecular weight
distributions (differential mass fraction profiles) of SEC-separted starch glucans: wheat
(⎯⎯); weight average molecular weight, M w = 5.5 ⋅ 10 6 g/mol; number average molecular
weight, M n = 0.78 ⋅ 10 6 g/mol; waxy maize (⎯⎯) weight average molecular weight, M w
= 21.5 ⋅ 10 6 g/mol; number average molecular weight M n = 1.95 ⋅ 10 6 g/mol.
22.4.2 MOLECULAR CONFORMATION — BRANCHING ANALYSIS
The influence of variations of molecular conformation, such as type of branching
pattern, tendency to form supermolecular structures, and how volume is occupied
by these materials, of starch polysaccharides on material quality is often underesti-