Chemical and Functional Properties of Food Saccharides

© 2004 by CRC Press LLC
Obviously, the critical temperature and disintegration temperature range depend on
molecular-level characteristics: short-chain branched (scb) waxy maize glucans are
intramolecular stabilized and thus stand applied thermal stress better than do wheat
starch glucans with pronounced long-chain branched (lcb) contributions (Figure
22.4). Increasing thermal energy disintegrates wheat starch glucans at significantly
lower temperatures and a smaller temperature range (56–62°C; T max = 58°C) than
for waxy maize glucans (65–85°C; T max = 78°C). Based on these data, it is obvious
that for a proper classification, efficient and comprehensive analytical strategies have
to be applied to complement the list of technological parameters with molecularlevel
characteristics.
Mass Fraction
Eluent Pump Injector
0.08
0.06
0.04
0.02
0
Separation
system:
SEC
LS
Visc
Mass
Flow
meter
10 20 30 40 50 60
Re [nm]
Fraction
collector
0.08
0.06
0.04
0.02
FIGURE 22.4 Stability of starch glucans on applied thermal stress. Viscosity at increasing
temperature. Waxy maize (⎯⎯): high initial stability, disintegration peak starting at 65°C.
Wheat (⎯⎯): minor initial stability, disintegration peak at 56–62°C.
0
Molar Fraction