This article is from the Sourdough Starters FAQ, by Brian Dixon briandixon at hotmail.com.
* If the starter has not been used in more than 3 or 4 days, you may
wish to replenish the starter once (1 cup starter, 1 cup water, 1 1/2
cups flour, 12 hours at 85 degrees) to ensure the starter is really
fresh before preparing for a bread recipe. Most healthy starters are
fairly flexible, though.
* Use the following table for amounts, and blend together the
starter, bread flour (if wheat) and/or other flour(s), and 80-85
degree liquid (water, milk, or whatever). Measure the starter and
liquids carefully. The suggested amount of flour(s) is only a
guideline. Blend enough in to make the starter the consistency of
mud (a little thicker than pancake batter). It is better to add the
specific amount of non-wheat flours that you intend to use, then use
wheat flour to adjust the consistency:
Loaves Flour Liquid Starter
1 1 cup 1 cup 1 tablespoon
2 2 cups 2 cups 1 tablespoon + 1 tsp
3 3 cups 3 cups 2 tablespoons
* Proof for exactly 24 hours at 72-77 degrees.
* Concurrent to the above proof, replenish the original starter by
combining 1 tablespoon (discard most of the rest), 1 cup warm water,
and 1 1/2 cups all-purpose flour in another bowl or in the starter
container itself. Proof for 24 hours at 72-77 degrees.
* Refrigerate the starter in the starter container.
 
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