Here are some comments for Maureen, who asked about sourdough in a bread
machine, and Lynne, who lamented that her new starter isn't very sour.
Sourdough is made with a much more slack dough compared to straight yeast
dough, with very long and cool rising periods to develop flavor. It must
also be handled very gently, with minimal degassing when shaping, so that
one ends up with an open and irregular crumb structure. In addition, it
must be slashed with a lame, and baked in a hot oven, generally with a cast
iron skillet of boiling water below the loaves. (This adds steam to mimic a
commercial steam-injected bakery oven, to develop the right crust.) I
would suggest Crust and Crumb, by Peter Reinhart, as a good reference book.
All of these characteristics are pretty much out of sync with a bread
machine. A wet dough will likely fall in the bread machine, and the
proofing period is too warm and too short to be of much use in developing
flavor in the finished loaves. I have found that sourdough is best
made entirely by hand, as good things come to those who wait. (I have been
using and replenishing a starter for over 3 years, given to me by a friend
who was trained in Germany as a chef, and has since moved back to Europe,
so I cannot give you any specifics of the ingredients of my very active
starter.) It does take some time to build sourdough, but it is time that
you may spend doing other things, and only intermittently playing with
dough.
As for sourness, sourdough isn't necessarily sour, unless one is making it
in San Francisco, or using additives to impart a sour flavor. The local
wild yeast in your kitchen will color the flavor of the starter, so even if
one began with a starter than was made in San Francisco, over time and
replenishing it would change as the local yeast overtakes the original wild
yeast.
The sourdough does give a certain texture to the crumb of the loaves, so
that it is moist, even without any fat in the dough.
Happy Baking!
Carolyn