Pan De Mic(he): bread for a pandemic

The pandemic lock-down has us cooking more than normal, but we've been making our own bread for years, some sandwich bread and some rustic round loaves or "miche" style. Many folks are picking up baking, and it's gotten hard to find flour and yeast now, so I figured I'd try propagating the yeast from a previous batch for this one; this is a pâte fermentée (old dough). The use of a pre-ferment is commonly done, with firmer or wetter starters, factory or wild yeast, salt or unsalted: biga, poolish, barm, etc. I'm going to start simply with old dough: maybe later I'll try it with a purpose-made pre-ferment or a wild yeast sourdough starter.

I reserved 100 g from my last pizza dough, an Italian 00 flour base with 70% hydration and about 2% salt (bakers percent). I froze it for a couple weeks, and it revived happily when brought to room temperature. I'll use this as my starter, instead of adding yeast, and save some of this batch to start the next. This keeps the math and procedure easy, since I don't have to worry about different hydrations in the pre-ferment versus the final dough: both are 70% and contain salt.

This time, I'll try something else new for me: give the flour and water a mix and overnight rest to allow the enzymes to break down some starches, which should improve flavor; keep the salt out of this rest so it doesn't inhibit the enzymatic reaction.

We've got some Whole Wheat flour that needs attention, so I'll add some of that into the mix for flavor. I use my usual high-hydration, low-knead, long rise technique. Here goes!

100 g  Pre-fermented Dough, 70% hydration, salted, frozen
800 g  All Purpose Flour (King Arthur, 11.7% protein)
200 g  White Whole Wheat Flour (King Arthur, 13% protein)
700 g  Water
 20 g  Salt, Kosher

Bring the fermented dough saved from a previous batch out of the freezer and put in the fridge to thaw.
Mix the Flours and Water, cover and let sit at room temperature overnight to let the enzymes break down starches to sugars; you can just leave this sitting in your mixer's bowl for convenience.
The next day, add the Salt to the rested Flour and Water.
Cut the saved, fermented dough into bits and mix into the bowl with Flour, Water and Salt.
Mix to combine well: I use a Kitchen Aid with dough hook, but use a minimal knead.
Put into a plastic bucket with lid and leave at room temperature to let the pre-fermented dough activate.
Once it's risen a bit, put in the fridge to rise (ferment) until doubled for one to three days. The longer and slower the rise, the more flavor will be extracted from the flour.
Take the dough out of the fridge a few hours before you plan to bake, to allow it to warm to room temperature.

Reserve 100 g of this actively fermenting dough in a tub for the next batch!  Put in in the fridge if you'll bake again soon, or the freezer if more than a few days.

Divide remaining dough into two balls and shape -- as a miche, boule, baguette, whatever you like; cover and let rise.
I'm going to make a miche in a "cloche", because the intense heat and trapped moisture give a good rise and crust with little effort.
I find it convenient to rise the shaped rounds on parchment in a mixing bowl, so I can use the paper as a sling to transfer them into the hot pots.
Pre-heat the oven to 500F with a pair of heavy lidded pots; I use a Le Creuset Dutch Oven and a clay Rummertopf.
When the bread's risen, carefully remove the pots from the oven, remove the lids, and transfer the dough on their parchment slings into the pots; replace the lid and put back in the oven.
Bake for about 30 minutes; the hot environment and trapped moisture will give a good oven spring.
Remove the lids, and bake another 30 minutes at 400F so the center bakes through.
Remove pots, transfer bread to cooling racks.
Enjoy the sound of the crust cracking as it cools.

Results: disappointing, yeast exhausted?

The pre-ferment revived nicely, rising in its tub, and the bread rose well, initially, but after a punch-down and redistribute, it failed to rise much in the final rise. The only reason I can imagine this happened is that the dough had over-risen, and when punched-down, there wasn't enough food left for the yeast to eat and rise again.

This resulted in rather flat loaves. The short stature was also abetted by splitting the dough into two cloches so they spread rather than rose; I should have put the entire batch into one cloche for more loft. 

I'll try this again, but will try to watch my timing so that the pre-ferment is very active, and I don't over-rise the dough; maybe don't bother with a punch-down, just shape and rise for the cloche.