What makes a bread either close or open crumbed
There are several factors that make bread be "holey". First of all we must understand that those big holes are created by "balloons" of gluten filled with CO2 and alcohol made by yeasts. Those balloons can grow in 2 ways
Yeast cells close to the balloon make CO2 or alcohol, and it's "poured" into the balloon, and it grows.
Most breads have 2 fermentations: bulk one and proofing. Do just one. The more you handle the dough, the higher chances to degas it by breaking bubbles and letting the gas get out of the dough.
Good answer. A thing to add: the variables you listed are not independent. As higher hydration breads rise quicker, you don necessary get a more open crumb, both effects seem to cancel each other out under the "wrong" conditions. Also, I still do a double-rising for open-crumb bread, just pay attention not to handle it gently. But the redistribution of the holes between the two proofings gives it better structure,
shamballa bracelet, even though some gas is lost. No deliberate punching down, of course. rumtscho Oct 30 '12 at 11:59
The main factor in the openness of the crumb is hydration. A higher hydration dough will generally have a more open crumb with larger, more uneven holes. A lower hydration dough results in a denser loaf, with smaller holes.
As well as hydration, fermentation time also plays a role. Usually these go together; a low hydration dough like a normal white sandwich bread usually has a relatively quick fermentation of 2-3 hours, whereas a high hydration dough like a ciabatta or focaccia can ferment overnight or even longer.