Attempt to replicate Larraburu Bros. San Francisco Sourdough

San Francisco Sourdough from Larraburu Brothers

as described in

https://www.aaccnet.org/publications/cc/backissues/1978/Documents/chem55_461.pdf

as interpreted by

David Snyder

February, 2019

Over many years, there has been much interest in reproducing the San Francisco Sourdough bread baked by Larraburu Brothers' bakery that closed in the early 1970's. The article referenced above seems the most likely accurate report available of Larraburu Brother's method. The following formula and methods have been extracted from that article, with a very few modifications as noted.

Note: I used King Arthur Flour AP flour (11.7% protein) and Breadtopia's "High Gluten Bread flour (14% protein).

One day before baking the bread (e.g., before going to bed the night before you want to bake)

1. Dissolve the starter in the water.

2. Add the flour and mix thoroughly. Knead until all the flour is moistened.

3. Place in a dry bowl and cover.

4. Ferment at 80ºF for 9-10 hours

5. Remove 50g of the fermented sponge and refrigerate for future use.

Procedure

1. In a large bowl or the bowl of a stand mixer, mix the water and sponge cut in pieces to soften the sponge.

2. Mix the salt into the flour and add it to the mixing bowl.

3. Mix the dough at slow speed to thoroughly mix the ingredients, then at medium speed to obtain medium gluten development. (A medium window pane.)

4. Transfer the dough to a clean, lightly oiled bowl. Cover and let rest at room temperature for 1 hour. (Note: The article does not specify the temperature for this step. I think room temperature is most likely.)

5. Divide the dough into two equal pieces. Pre-shape as balls. Cover with a cloth and let rest for 10-30 minutes to relax the gluten. (Note: The 10-30 minute rest after pre-shaping is my addition, but it is “standard operating procedures” in most artisan bakeries.)

6. Shape the pieces as boules or bâtards and place, seam-side up, in floured baskets or on a linen or parchment couche.

7. Proof for 3-4 hours at 105ºF in a humid environment. (Note: I placed the formed loaves in bannetons and place the bannetons in food safe plastic bags and clip them shut. Then, I proofed the loaves in a Brød & Taylor proofing box.)

8. One hour before baking, preheat the oven with a baking stone and steaming apparatus in place.

9. Transfer the loaves to a peel and score as desired.

10. Bake at 460ºF for 15 minutes with steam, then at 450ºF Convection bake for another 25 minutes in a dry oven. The loaves are done when thumping the bottom gives a “hollow sound,” the crust is nicely browned and the internal temperature of the loaves is 205ºF.

11. Cool thoroughly before slicing.

Notes for future bake: Relatively dull crust suggests either over-proofing, insufficient steam or both.

The crumb was well-aerated, demonstrating adequate fermentation, but quite dense. It was essentially identical to other loaves I have baked with 50-60% hydration doughs. There is no danger of your jam falling through big holes onto your lap with this bread! The flavor was that of a French pain au levain - sweet and wheaty with only the subtlest lactic acid overtone. There was essentially no acetic acid tanginess. It's good white bread but not anything I would identify as "San Francisco Sourdough."

I could fiddle with the hydration and flour mix, I suppose, but I am not optimistic about the basic method ever hitting the target.

David