Cereal Chem 41:216 - 229.  |  VIEW ARTICLE

The Elastic Modulus of Bread Crumb in Linear Compression in Relation to Staling.

S. J. Cornford, D. W. E. Axford, and G. A. H. Elton. Copyright 1964 by the American Association of Cereal Chemists, Inc. 

It is shown that the relationships between elastic modulus, time, and temperature in bread crumb, at temperatures above the freezing point of bread, are such as would be expected if the process causing an increase in crumb modulus were an increase in crystallinity of the material: the extent of crystallization would then be measured in terms of the increase in crumb modulus, E, in relation to its limiting value, E1, which would be reached after a long period of storage. If the relationship were linear, the fraction of uncrystallized material, Theta, remaining after a time t, would then be measured as Theta = (E1 - Et)/(E1 - Eo), and this function was found to follow the equation, Theta = exp (-kt). The rate constant, k, decreased with increasing temperature of storage in the range 30 to 90 F.; E1 was the same for any given batch of bread at different temperatures. Thus, no matter what the storage temperature above freezing point, the bread is tending toward the same value of the crumb modulus, although the rate decreases as the temperature increases. Addition of compound fat reduced the value of E1 without significantly affecting k at any given temperature.