Premium
Multiple Phase Transitions of Starches and Nägeli Amylodextrins
Author(s) -
Donovan J. W.,
Mapes C. J.
Publication year - 1980
Publication title -
starch ‐ stärke
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.62
H-Index - 82
eISSN - 1521-379X
pISSN - 0038-9056
DOI - 10.1002/star.19800320604
Subject(s) - crystallite , amorphous solid , starch , starch gelatinization , phase transition , melting temperature , glass transition , materials science , hydrolysis , chemical engineering , chemistry , crystallography , polymer , thermodynamics , food science , composite material , organic chemistry , physics , engineering
At temperatures above that required for gelatinization, an order‐disorder transition is observed for wheat, maize, waxy maize and potato starches. This transition is the melting of the crystallites in the granules. A second, higher temperature, transition occurs in wheat and maize starches. This also appears to be a melting transition. Potato starch Nägeli amylodextrins show increased thermal stability of the crystalline regions with increasing hydrolysis of the amorphous regions. Extensive hydrolysis lessens the destabilizing effect of the amorphous regions on the crystallites sufficiently that the gelatinization transition occurs to only a small extent, the crystalline regions melting, instead, at temperatures above the gelatinization temperature.