Baking with Sourdough

Over the years, I've given out my starter along with a sheet of instructions. Now that I have a website, I can simply pass along the URL.

I don't think there's anything special about these instructions. I've been baking bread for about 20 years, and sourdough for 12, and they seem to work pretty well. You'll find plenty of additional information at Sourdoughs International founded by Ed Wood, the author of World Sourdoughs From Antiquity. There's also the FAQ from rec.food.sourdough, and more Google-able sites than you can shake a dough hook at.

The Secret of Sourdough

When I got my first sourdough starter, I searched Usenet for information about baking with it. There was one frequent poster — I can't remember his name — who seemed obsessed with the “secret of sourdough.” He certainly believed that he had found that secret, and would test newbies to see if they too possessed it.

I doubt that I measured up, but to my mind the secret is simple: pay attention.

Bread, even sourdough, is one of the most forgiving things that you can cook — provided that you pay attention to it, and don't try to make it fit a schedule or an exact recipe. This applies to all breads: people who end up with bricks are following a recipe's one-hour rise, rather than looking at the loaf to see if it has risen. On the other hand, if you pay attention then you can bake damned good bread in a charcoal grill.

My recipe

To that end, my recipe is all about process. For a “normal” loaf of bread, it takes 36 hours from the time you take the starter out of the refrigerator (typically on Saturday morning) to the time you take bread out of the oven (typically just before Sunday dinner). Of course, that isn't time that you have to spend standing over it: in fact, total work time is on par with breads using commercial yeast. It's also very forgiving: since sourdoughs generally rise slowly, you can extend the times by several hours.

There are four steps to this process (and here are some photos):

Starter

Starter is quite literally the soul of sourdough: it gives life to an inanimate mixture of flour and water, and it persists after the bread has been baked and eaten.

OK, now without the pseudo-mysticism: the starter is a mixture of flour and water that serves as a culture medium for the sourdough's yeast and bacteria. Keep it in a loosely-covered, non-reactive container in the back of the refrigerator, and feed it with equal parts of flour and water when you're ready to make bread.

1 cup
all purpose flour
1 cup
water, filtered if possible to remove chlorine

I keep my sourdough starter in a ceramic crock. I move it to a 1-½ quart Visions saucepan for feeding, and wash the crock with lots of hot water. You can also use a 4 cup Pyrex measuring cup, loosely covered with plastic wrap.

When you take the starter out of the refrigerator, it will have separated into a thick, gummy flour mixture, covered by a gray liquid that smells like alcohol (because it is). Stir this as best you can, then add the flour and water, and stir until mostly combined. You're looking for something the consistency of pancake batter, but lumps are OK — they'll break up as the yeast and bacteria get to work.

Let the starter sit for 4–6 hours in a “room temperature” (72°) kitchen. Don't stress about the ambient temperature: my kitchen stays around 60° in the winter, 80°+ in the summer; different temperatures simply require different fermentation times. Don't stress the time either: you can let the starter ferment all day if it's more convenient. Remember, it's more important that you pay attention to how it looks, not the clock.

The starter will bubble up as the yeast gets to work, and will start to smell “distinctive” as the bacteria get to work. Each starter has its own smell, but it definitely won't smell like a simple flour-and-water paste.

The starter might start to separate, particularly on a warm day. Simply give it a stir whenever you pass by. It should be very frothy when you're ready to make the sponge.

If your starter doesn't get frothy after feeding, throw away all but ¼ cup and try again — this time with 2 cups of flour and water, and give it more time (say, overnight). If it doesn't froth up then, throw it away and get a new starter.

Sponge

The sponge is a stage halfway between batter and dough, and I believe it's the stage in which the bread develops most of its flavor. I normally make the sponge on Saturday night, after letting the starter feed for the day. It contains all the water and half the flour of the final loaf.
1 ½ cups
active starter
2 cups
all purpose flour
1 cup
water

Mix the flour, water, and starter. You don't have to get all the lumps out, but you don't want big globs of dry flour. Put in a big bowl — I usually use an 8 cup Pyrex measuring cup — and let sit for eight hours or more (in my prototypical timeline, overnight Saturday).

The sponge will typically expand to fill the bowl in the first four hours or so, as a very loose, wet dough with big gas pockets. Then it starts to collapse in on itself, and after eight to ten hours will be back to the volume that you originally mixed.

You have a great deal of flexibility in how long you let the sponge ferment: while I nominally let it ferment overnight, I've let it go for days with no ill effects other than a sticky, slack dough.

Dough

Add the following to the sponge, and knead as with any other bread dough.

2 tsp
salt
¼ cup
bran (wheat or oat)
2 ¾ cups ±
bread flour

OK, first item to pay attention to: the flour. Nominally, 1 cup of water hydrates 3 cups of flour. But that varies, depending on how dry the flour is, which is why most cooking show bread recipes specify flour in terms of weight. Rather than specifying an exact measurement of either type, I simply add enough flour to make what I consider a good bread dough: one that is moist but not overly sticky. This is where experience with bread baking really helps: once you know the feel of good dough, you don't need to measure.

You'll notice that I specify bread flour for this stage of the recipe. The sourdough culture breaks down gluten, which means that the 3 cups of all- purpose flour are for the most part unrisable (particularly if you let the sponge ferment for several days). Bread flour has higher protein (gluten) content than all-purpose, so that compensates. You can use all-purpose in this step, but be prepared for loaves that don't rise as well. Or you can add pure gluten, which you should be able to find at natural foods supermarkets.

The bran is there for texture and appearance: it just looks nicer to have little flecks of brown in the loaf. It also increases the fiber content, and perhaps changes the flavor slightly, but not enough to make a difference. In the interest of full disclosure, the idea of adding bran came from the bread that I got at Salamander; up to that point, I either made whole wheat or white.

This recipe makes enough dough for two standard (9x5) loaf pans. I prefer glass pans, because I think it makes for a nicer crust, and I butter the inside to make the bread release easier (and give some flavor to the crust).

Rising time is extremely variable. Different sourdough cultures will have different rising times, and the same culture will have a different time depending on factors such as ambient temperature, length of time in each stage, and phase of the moon. Well, maybe not phase of the moon — but you never know!

So, pay attention to the dough, and when it's reached the top of the pan you can fire the oven. Generally, this takes around 4 hours for my culture, rising in the room-temperature microwave oven (the microwave is a convenient space, with a door, where the loaves won't get bumped).

Bake

Preheat the oven to 450°F. Yep, that's hot, hotter than most bread recipes. The higher your initial oven temperature, the nicer the crust and the more “oven spring” you get from the dough. Note that most ovens sound their “preheated” alarm well before they've actually reached temperature; use an oven thermometer.

Put the dough in the oven, and set your timer for 10 minutes.

After 10 minutes, reduce heat to 325°F, and bake for another 20 minutes. I've seen a lot of recipes that over-bake the bread: one suggested two 40 minute segments! The bread is done if it comes out of the pan easily, and sounds hollow when you tap it. I've never had to put bread back in the oven, but if you don't think it's done, give it another 10 minutes.

When you take the bread out of the oven, immediately turn it out of the pans onto a cooling rack. If you leave it in the pans, it will get a soggy crust. Ditto if you put it in a plastic bag or other sealed container before it's fully cooled.

Wait a half hour for the bread to cool, slice into inch-thick slabs, cover with butter, and eat.

Observations, Thoughts, and Suggestions

It helps (a lot) if you've baked with commercial yeast before trying sourdough. There's definitely a technique to mixing and kneading, knowing when the dough feels right. Written descriptions such as “smooth and elastic” can't substitute for that experience. Since commercial yeasts are very predictable, you can gain experience while following the rigid steps of a recipe.

The more frequently you bake with starter, the more intense the flavor will be. I can't give a good explanation for this: it can't be as simple as the bacteria (which give sourness) going dormant, because they have ample time to become active in the sponge.

Starters vary in their response to neglect. I've left mine in the fridge for weeks at a time, and it responds well once fed. However, ever since killing my first starter by freezing, I've been diligent about feeding it through the summer, even when the house is too hot to endure baking.

The longer you let the dough rise before baking, the more sour it will be. There's a point, however, when the bread has risen too long and it collapses, its gluten weakened by the acid environment. You can still bake at this point, and with a high enough oven temperature you should get enough “oven spring” to make a passable loaf.

I rarely do a two-step rising (first in the mixing bowl, second in the loaf pans). I think this practice exists to give flavor to commercial yeast breads, which can rise too quickly and end up tasting bland and alcoholic. The second rise gives the yeast a chance to break down more of the starches in the bread. Since sourdough rises very slowly to start with, and has had the long fermentation in the sponge stage.

One of the questions on the sourdough FAQ is about using a bread machine. If you have a machine that can program separate kneading and baking stages, it's no problem: knead, pay attention to it while rising, and then start baking when it's ready. Oh, and you'll need to adjust the proportions to suit the bread-maker's capacity. I generally skip the sponge stage to do this. Bread makers are a good way to get sourdough through the summer, although oven-baked bread just tastes better.

Sourdoughs have remarkable keeping properties. Where regular bread will go moldy inside of a week (if it lasts that long), a sourdough will keep for two weeks or more. It does dry out, so progresses through the stages of sandwich, toast, and french toast during that time.

Toasting sourdough really brings out its flavor.

Don't limit yourself to the basic recipe described here. Sourdough rye — or better, pumpernickel — is amazing. It also takes you back to the roots of bread baking, before modern strains of wheat and precise milling. Since rye flour doesn't have much gluten, you'll need to mix with wheat to get a good rise. I generally use rye for the sponge (never adulterate your starter!), with another cup in the final dough. You may also need to adjust water slightly, but again it comes down to two words: pay attention!.

Copyright © Keith D Gregory, all rights reserved