Sourdough bread, 50% wheat


To make a sourdough boule with starter recently obtained from our friends C&M who received it at a starter workshop hosted by SF-based Sour Flour.



  • Starter
  • Bread flour
  • Whole wheat flour
  • Salt


  • Kitchen scale
  • 2-4 C container with lid for maintaining starter
  • Stiff spatula
  • 1-2 Dutch ovens, or heavy pots with lids that are safe to 500 F
  • 2 proofing baskets or towel-lined mixing bowls
  • Counter top or pastry mat
  • Good bread knife
  • Optional: bench scraper/pastry cutter


This protocol was adapted from The Kitchn “How to Make Sourdough Bread“, which is a scaled-down and well documented version of the contemporary classic Tartine country sourdough bread. Please refer to these sources for technical details.

  1. Starting Tues or Wed, discard all but a tablespoon of starter every 24 h in the evening. Add 25 g bread flour, 25 g whole wheat flour, and 50 g water. Stir to combine, and let sit at room temperature in a loosely capped storage container (ours is a 2C gladware).
  2. Friday evening, make the leaven: mix 1 Tbsp starter with ~37.5 g bread flour, ~37.5 g whole wheat flour, and 75 g water. Mix and let sit, loosely covered, overnight (8-12 h).
  3. Stir in 475 g water, making sure leaven is well dispersed.
  4. Use a stiff spatula to stir in 350 g bread flour and 350 g wheat flour until no more flour is visible.
  5. Autolyse – wait 30 m with dough loosely covered. Meanwhile, dissolve 1 Tbsp salt in 50 g warm water.
  6. Add the salt water, squeezing the dough with your hands to mix it in.
  7. Fold the dough four times, with a quarter turn between each fold. Let rest 30 m.
  8. Repeat step 7, for a total of 6 folding cycles (3 h).
  9. Shape the dough into two rounds and rest 20 m.
  10. Place each round into a floured proofing basket with the seams from shaping up. (My “proofing baskets” are mixing bowls lined with thin dishtowels that I’ve rubbed flour into.) Loosely cover.
  11. Let rise 3-4 h at room temperature or overnight in the fridge.
  12. Heat oven to 500 F with two Dutch ovens inside for 30 m. (I didn’t have any Dutch ovens, so I used the inside of my slow cooker for one loaf and a large pot for the other. I covered both with foil.)
  13. Dump the dough into the Dutch ovens, score the loaves, cover, and bake 20 m.
  14. Reduce the oven temperature to 450 F and bake 10 m.
  15. Remove lids and bake 15-25 m further, to a deep brown.
  16. Cool completely on racks before cutting.


Most bread recipes and bakers will tell you to feed your starter at least every 12 h. This is true if you want to be able to bake at any time on any day. I’ve had success with 24 h feedings for 2-3 days leading up to baking and a final feeding (to make the leaven) 8-12 h before baking, and keeping the starter in the fridge between bakings for up to 2 weeks. This saves flour. In a research laboratory, yeast are stored long term with glycerol at -80 C, or short term streaked out on agar with nutrients at 4 C, and then grown in liquid broth with nutrients for some period leading up to experiments.

Results and observations:

Proofing stage


Coming out of the oven


This picture was taken 15 minutes into step 15, the minimum suggested time for the uncovered bake. I’m not sure if you can see from this picture, but the inside of the slow cooker was a MUCH better baking vessel than the pot. It was thicker, so it retained and distributed heat better, and shallower, so it retained steam better while covered and made it easier to score the loaf once the dough was placed in. I took the loaf in the pot out immediately and gave the one in the slow cooker a few more minutes to brown. The bottom of the one in the pot was burned, and the one in the slow cooker ended up with a little tougher bottom crust than I like.

Finished loaves


The loaves had nice oven spring and the one on the left was nicely scored, while the one on the right – not so much. Both had a great deal of flour left on them from the proofing baskets.

The crumb


The bread had a fairly open crumb on the outside and more dense toward the center. It was tasty, with prominent but not overpowering sourdough tang. We ate it just like this!


The inside of the slow cooker is an acceptable baking vessel, while the thinner pot is definitely not. I’ll put a Dutch oven on my Christmas list. Next time, I should tap out some of the flour after lining the proofing baskets so the loaves don’t end up so floury on the outside. Overall, we were happy and full from the first attempt, and learned a lot about the process and timing. Baking bread is a great excuse to stay home all day on a Saturday!


Our kitchen notebook

Welcome to my first blog post since studying abroad in college! I just finished my PhD in September, and I now have much more time to perform experiments in my second laboratory, our kitchen. I am a biochemist with a background in working with yeast, and I love to bake. My husband, Ryan, also enjoys cooking and baking and, conveniently, photography. During grad school I kept an electronic, but private, laboratory notebook, and I thought it might be fun to have a public lab notebook blog for our kitchen experiments. You can expect roughly weekly monthly posts in a roughly scientific format. I promise to report both successful and failed experiments, and I welcome discussion of the results and conclusions!