Joe inquired about the development of holes in yeast breads. An open crumb
structure with lots of large irregular holes is typical or rustic and
sourdough breads. Long cool slow rising periods in addition to gentle
handling of the sponge and dough contribute to this holey texture. Minimal
degassing when shaping the dough is also important. This means that you do
not punch down the dough with much force. Instead, it is handled very
gently so as to preserve the accumulation of carbon dioxide bubbles that
the yeast has created in the rising process.
Happy Baking!
Carolyn