Sourdough from scratch

Sourdough from scratch is now hosted at Pie of the Tiger

I figured that I would finally come out of my hive and talk about the sourdough bread I spent a week working on while I was snowed in before Christmas. As you may have inferred from other posts here, I'm basically cooking my way through The Bread Baker's Apprentice, which I think has to be about the best book around if you want to learn how to bake professional quality artisan bread at home. I apologize if my photos aren't as good as Tiger's usual ones -- these were taken before we started using better lighting.

Because I'm cooking from a book, I don't think I can reproduce the recipe in this blog without a copyright violation, so you'll have to bear with me until I can come up with a few of my own recipes before you'll see many ingredient lists. With that said, I love this cook book, and think it's a necessity for any home baker's bookshelf.

The Barm (also known as a starter)

One of the best starters that Tiger remembers from pastry school is started with organic grapes (which are covered in wild yeast). When we couldn't find the particular recipe, we turned to the internet and found a good set of instructions. I got myself a pound of grapes from Whole Foods (they have to be organic and unwashed/treated -- the non-organic ones don't have enough wild yeast still living on them).

The recipe is fairly easy, so I'll let you read the details on your own. Basically, you squish up the grapes (throw out any bad grapes and brush off any dirt, but don't wash them) and let them sit for a few days. Once they start to bubble, you strain out the skins and start feeding it with bread flour. Once you have a good seed culture, you can alter the flavor by your feeding schedule. I find that feeding the sour by weight is more reliable than by volume, but the most important part is to make sure that the ratio of flour and water are the same. The Bread Baker's Apprentice suggests that you can double, triple, or quadruple the barm -- the higher the ratio of flour and water to starter, the less sour your final bread will taste. I like to use this for sourdough, so I usually feed at 1::1 (usually 8 oz of starter, to 8 oz each of water and flour) unless I plan to store it for awhile in the refrigerator (in which case I'll often do a triple volume feeding).


You should also know that storing your barm in the fridge will help produce a stronger sour taste. This is because the bacteria that produce the sour flavor generally work slower than the yeasts in the barm, but the cooler temperatures will slow down the yeast and let the bacteria catch up.

Firm Starter
With many artisan breads, you make an overnight starter (there are actually three main variants of this, based primarily on the amount of liquid: biga, poolish, pâte fermentée). With non-sourdough breads, you would usually just mix up flour, water, yeast, and occasionally salt. With this bread, you make the overnight starter with the barm instead of yeast. Once you mix the barm with flour and water, you let it sit on the counter for around 4 hours, and then toss it into the fridge overnight to improve its flavor. This part is important because it allows the sour flavor to develop.

Dough

On day 2, take your firm starter out of the fridge and cut it up into a bunch of small pieces to warm up for an hour. I put mine on a silpat and covered them with plastic wrap to keep them from drying out. Next, you mix the firm starter in with your other ingredients. Though the recipe calls for about 20 oz of additional white bread flour, it also says that the other flours can be substuted. Following the advice in the baguette recipe from the same book, I decided to substitute about 1/4 of the bread flour with sifted wheat flour. I like King Arthur Flour's white whole wheat flour, so I sifted it to remove some of the larger pieces of what bran (which can cut gluten and make proper rising/shaping more difficult). The (now mostly) whole wheat flour will add a bit more complexity to the overall sourdough loaf, and make it slightly healthier.



Understanding gluten development is one of the most important parts mixing good bread dough. If the gluten does not develop properly, you won't be able to shape the dough, and when it proofs, it will stretch outward instead of upward, resulting in a very dense loaf. The trick is what's called the "window pane method", which is demonstrated in the two images to the right. The first image shows dough that is not yet ready -- notice that it breaks easily. The second shows dough that stretches thinly and allows light to pass through fairly easily. A few breaks are OK, especially when using even a little whole wheat flour, but the dough should be able to stretch fairly thin.

I've found that a good test for the time left for gluten development is to take a small piece of dough (usually the same one I use for the windowpane test) and roll it around between my hands to knead it very quickly. This way, you can stretch it again and see if more kneading will improve the gluten development, or if you have reached a point where more kneading will actually start to break the gluten strands because they have been stretched too tightly.

Once your dough is ready, it goes into a big bowl, tossed with a little oil (I just use a good organic spray oil), coated in plastic wrap, and left to ferment (i.e. rise) for several hours. The wild yeasts in a homemade sourdough rise a lot slower than commercially available bread yeast, so this phase takes 3-4 hours instead of the 1-2 that is more common for other bread types. You can do this at room temperature, but I happen to have a "bread proofing" mode on my oven and I prefer to use that.

Shaping

After the dough has risen and approximately doubled in size, carefully divide it into two pieces (being careful not to punch it down any more than necessary) and shape them into whatever shape you prefer for your loaves. In my case, I used a couche (well, actually a fine-weave kitchen towel because it costs less and works just as well) and shape into a somewhat elongated loaf. Once again, these get spritzed with a little oil, covered in plastic wrap and are set aside in the proofer (to actually proof this time) for several more hours.


I've determined that it takes about 30 minutes for my oven to heat, so about half an hour before my proofing time is up, I turn my oven up to 500° F and make sure that my baking stone and a large hotel pan are in place. The hotel pan (or other large metal pan) is another trick from this book to help emulate a professional baking oven by providing steam -- more on this later.

Once the oven was hot, I started boiling water for the steam pan, and removed my bread from the proofing drawer to slash. Carefully roll the proofed loaves off of the couche and onto a baking peel that has been prepared with cornmeal.

Slashing the bread not only provides an attractive look, but also breaks the tight skin around the loaf that you get from properly shaping. This exposes the moist insides of the loaves and encourages them to rise upward in the oven, instead of spreading out.

Baking
Once the oven is hot, your loaves have been slashed, and the water is boiling, you're ready to bake. Slide the loaves off of the peel onto the baking stone, toss one cup of boiling water into the steam pan, and close the oven door. The steam will provide a humid environment that lets the bread rise more before the crust sets, as well as contribute to a much crispier crust once the steam has dissipated.

The book suggests that I should open the oven door several more times at 30 second intervals, spraying the sides of the oven with water each time. However, I've discovered that it's very easy to shatter the light bulbs in an oven with a little misplaced water. Instead, I've noticed that the water in the steam pan doesn't boil off quickly enough and I am left with a humid oven that doesn't let the crust harden enough, so instead of spritzing, I just shake the steam pan around a bit to make its water boil again. I've found that it's more helpful to use a large thin-sided hotel pan instead of the cast iron frying pan I was originally using, both because of its larger surface area, and because it heats up much faster. About 90 seconds after putting the bread into the oven, reduce the temperature to 450° and bake for 10 minutes.


After 10 minutes, remove the steam pan if it still has any water in it, and rotate your loaves 180° for even color. Bake for another 10-12 minutes until the loaves are done, and remove them to a wire rack to cool for at least 45 minutes. This is the most difficult time for me -- the house now smells like wonderful fresh bread, but I know that it's still technically cooking inside and won't be nearly as good. It's worth the wait, so let it sit.

Between the grape-based starter and the recipe, this is the first sourdough I've made that actually tastes sour. I'll definitely be making it again (or some variant of my own so I can share the recipe).