Staling of white wheat bread crumb and effect of maltogenic α-amylases. Part 1: Spatial distribution and kinetic modeling of hardness and resilience.

Bread staling is one of the most costly food deterioration processes. This study presents an in-depth, multivariate, statistical assessment of the differences in the staling process of white wheat bread as a function of storage time, usage of maltogenic α-amylases and spatial position in the loaf by texture measurements and non-linear fitting (Avrami). This study demonstrates the effects of anti-staling enzymes upon bread staling, where significant changes in the spatial staling kinetics occur. While the spatial development of staling is reduced in the outer crumb by anti-staling enzymes, the staling is retarded in the middle. The Avrami model suggests that this happens by two different competing mechanisms: one which increases the initial staling rate, and one which slows the convergence towards the limiting hardness. The two enzyme treated breads differed widely in early and ultimate resilience, despite the fact that they were adjusted to provide the same ultimate hardness.