When I worked at a bakery we mixed everything in a big spiral mixer, and everything mixed until it would pass a window pane test (even whole wheat). But when it came to the fermenting (first bulk rise) sourdough got a strech and fold every hour for 3 hours while French dough (poolish) did not. This, combined with the great videos I've seen here with French peasant bakers mixing levain-based bread by hand gave me cause to think about no-knead bread.
Is it the strech and fold that allows no-knead to work? So with a french dough, would it have to be a high hydration dough to be able to accept this approach? Stretch and fold on a more typical lower-hydration french dough (such as Leader's Country loaves from Bread Alone) seems antithetical.
Thoughts?
...are they from levain? sourdough? or are they a regular straight yeasted dough? High hydration? I'm not sure why to stretch and fold either when it already window panes. Our bakery was set up and trained by a French baker trained in France who had his own successful bakery in the States. So somebody must have had a reason for doing it that way.
A long time ago high hydration doughs were known as water doughs. The large amount of water aides natural gluten formation in the dough [enzyme action]. Stretch and folding builds that gluten into chains, aerates the dough [improved yeast production] and in the case of levain distributes the lactic-acid bacteria more evenly. The end result provides a healthy growth medium for the yeast and/or levain and a rubbery, elastic dough capable of holding CO2 bubbles. In the case of high hydration doughs that capability is enhanced by the gelationous structure of the dough allowing large sized CO2 bubbles to form.
Wild-Yeast
So are you saying that stretch and fold approaches are equally applicaple, yeast or levain, so long as it is a high hydration dough? This would seem to do well with an autolyse. But not so with lower hydration such as traditional yeasted french dough?
As Wild-Yeast said, S&F serves a number of functions. One not mentioned is the effect on crumb structure. S&F helps develop gluten. It is a substitute for longer mechanical mixing. In contrast to mechanical mixing, it results in a more chaotic gluten network and, thus, a more open crumb with holes of varying size, randomly distributed. This is desireable with baguettes as well as pains au levain. In addition, if you shorten the mechanical mixing, you also get less oxidation of caretinoid pigmenets and, thus, a yellower, less white crumb and improved bread flavor.
As far as I know, S&F is applied to both high- and low-hydration doughs. By "low-," I mean in the 65-70% range, not 50-60% as you might have with challah or bagels, for example.
Here is an example of 65% hydration sourdough baguettes mixed wholey by hand with S&F's: Baguette crumb - 65% hydration dough
David