A lean indirect dough is one that has no oil (shortening) and is made
with a preferment. In the case of Pain Ordinaire the preferment is
a pate fermentee, also known as scrap dough, which is complete dough,
often left over from the previous days' baking. A complete dough is
one that it contains flour, salt, yeast, and water and is the
consistency of finished bread dough. A biga, on the other hand, does
not contain salt but otherwise is the same consistency as a pate fermentee.
Preferments are made before, up to several days in the case of
sourdough, which gives the enzymes time to develop more flavor from
the flour. Poolish and sourdough starters (aka Barm) are more fluid
preferments while pate fermentee and biga are firm.
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