Subject: 25. How do I get holey, sour, moist and long keeping bread?
I get the most moist dough and most irregular holes when I have the most over mature dough. Unfortunately, this also correlates with lower loaf volume and more slump. However, if you look at the loaves pictured in French Specialty and Decorative Breads (or whatever the title is, I've lent out my copy), you will see that the bread fermented with old dough is like that - fairly flat round loaves, and that wonderful texture I seem to get most often when something goes wrong.
As far as allowing the dough to "proof" (I'd use the term ferment, or rise) for a few hours before shaping, that is my standard operating procedure. I usually let it at least double twice (punching down in between).
So, in general, if I always go to the next stage (starter to sponge to dough to loaf) when that stage is at maximum volume, I get less sour bread with more "conventional" texture. The more I let the stages go, especially the dough stage, the more holey, sour, moist and long keeping the bread is.
An irregular crumb is achieved with an extensible dough. This is most easily done using a "weak" flour. French bread flour (type 55) has a protein level which is extremely low by US standards (9 - 10 % vs 12%+). Using a weaker flour, highish hydration (65%+) and short mixing time is the surest way to get good irregular crumb, and don't shape your loaves too tightly. But don't expect enormous holes, as in ciabatta, unless you to extreme hydration. Of course, the lower protein flour will have less tolerance than a normal US bread flour, so be careful not to overproof.
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