Cereal Chem. 71:527-531 | VIEW
Correlation Between Glass Transition Temperature and Starch Retrogradation in the Presence of Sugars and Maltodextrins.
Y.-J. Wang and J. Jane. Copyright 1994 by the American Association of Cereal Chemists, Inc.
The stability of starch solutions containing sugars (glucose, fructose, maltose, and sucrose) and maltodextrin at concentrations of 6 and 9% was investigated. Differential scanning calorimetry was used to measure the retrogradation rate of gelatinized starch and to determine the specific glass transition temperature (Tg'), the glass transition temperature of a maximally freeze-concentrated solution. Starch containing low molecular weight molecules had a lower Tg' than those containing high molecular weight molecules. Starch with glucose and fructose exhibited greater retrogradation than did starch with maltose, sucrose, and maltodextrin after being stored at -20 C. The Tg' of starch samples containing sugars increased during storage. The temperature shift ranged from -0.7 C to +4.4 C for samples stored at 2 C, and -0.4 C to +3.7 C for samples stored at -20 C, after 21 days. The results indicated that the lower the (Delta)T value ((Delta)T = Tf - Tg') between the freezer temperature (Tf) and the Tg' of the sample, the greater the storage stability of foods.