Seth
Reggie is correct; there were a variety of recipes used around the
world to make berches or challah. The bread was typically made from
the finest flour available. Whereas daily bread was wholemeal wheat
or rye, etc, the flour used for berches was sifted to remove the
bran, rendering it (nearly) white. The recipes would have been
sourdough as the production of commercial yeast began in the late 19th century.
For more information, I'd suggest you consult the *Encyclopedia of
Jewish Food* by the late Gil Marks z"l and *A Blessing of Bread:
Recipes and Rituals, Memories and Mitzvah *by Maggie Glezer (who was
was a member of this list at the time she wrote the book).
Regards
Steven Leof