As the temperature declines, the starch
granules become firmer and so the loaf as a
whole becomes easier to slice without tearing.
This desirable firming continues over the
course of a day or so, and turns out to be the
first step in the process called staling.
The Staling Process;
Storing and Refreshing Bread
Staling Staling takes place in the days
following baking, and seems to involve the
loss of moisture: the bread interior gets dry,
hard, and crumbly. It turns out that bread will
stale even when there’s no net loss of
moisture from the loaf. This was shown in the
landmark study of bread staling in 1852, when
the Frenchman Jean-Baptiste Boussingault
showed that bread could be hermetically
sealed to prevent it from losing water, and yet
still go stale. He further showed that staling is
reversed by reheating the bread to 140ºF/60ºC: