Larraburu Starter Inconsistency
This post is for my fellow S.F.SD aficionados who have been trying to reverse engineer the Larraburu sourdough formula which has been published several times in different places over the years.
There appears to be an inconsistency in the formula described in the article by A. M. Galal et al. cited by doc.dough in another thread. The article, entitled Lactic and volatile (C2-C5) organic acids of San Francisco sourdough French bread, originally appeared in Cereal Chemistry 55(4): 461-468
If my math is correct, the Galal article calls for a 1/1/2 starter/water/flour refreshment of the starter sponge.
Now take a look at this document from the U.S. Patent Office:
1. Maintaining a continuous starter sponge comprised of two parts (40%) previous sponge, two parts (40%) flour and one part (20%) water by rebuilding every eight hours or three times a day;
This works out to a 2/1/2 refreshment and is consistent with the "other" S.F.SD process cited by doc.dough, viz.
Sour Dough Starter Sponge
100 parts previous sponge
100 parts flour (Hi-gluten)
46-52 parts water
This doesn't conclusively solve the mystery, but it points out the consistency between the formula in the patent document and the "other" formula cited above.
The definitive authority on Larraburu sourdough is the head baker and co-owner, a fellow named Richard Chamblerlin, who unfortunately is no longer with us.