Thanks to everyone for all their great suggestions and input on how
to convert my sourdough starter. I did double check the starter
recipe (which is from "Nancy Silverton's Breads from the La Brea
Bakery") and I'm fairly certain I'm correct. Her starter maintenance
formula calls for 3 daily feedings as follows:
First feeding:
8 ounces water
5.5 ounces flour
18 ounces starter
Second feeding:
16 ounces water
11 ounces flour
Third feeding:
32 ounces water
22 ounces flour
So, regardless of the hydration ratio of the starter in step 1 over
time the starter would (every nearly) achieve this hydration ratio
through repeated feedings. If I add up all the flour and water I get
56 ounces of water and 38.5 ounces of flour so 56/38.5 = 1.45 (145%).
After I sent my first message I did also consider that if I wanted to
make the conversion quickly (i.e. 1 or 2 feedings) I may also have to
account for the additional water that should've been present in my
starter. Therefore, if I use 8 ounces of 100% starter to begin the
conversion I would need to add the extra water that would have
present had the starter been maintained at 145%. For 4 ounces of
flour I should have 5.8 ounces of water for a 145% starter so I would
need to use 8 ounces of starter plus the "missing" 1.8 ounces of
water and then feed at 145% until I'm ready to bake. Do others think
this step is necessary? I could certainly adjust the dough by feel
as I'm making it, but nearly 2 ounces of missing water can be considerable.
I do appreciate Mike's insight that "thick" starters and "thin"
starters behave differently but I don't really have the time (or
energy) to maintain 2 starters so I'm trying to think of how I can
quickly adapt my 100% starter with the best mix of efficiency and
good baking outcomes. I'm relatively new to sourdough so if I'm
making incorrect assumptions, please let me know.
Thanks again for sharing your collection knowledge.