Sourdough Starter

For Those Who Want to Make Naturally Leavened Bread

In order to make naturally leavened bread (also known as sourdough or simply levain), you will first have to catch or acquire a colony of wild yeasts.
Wild yeasts are different from ‘commercial’ yeasts (Active Dry, or Quick Rise, or even the fresh moist cakes used in bakeries). You will not find them granulated in the baking section, but invisibly in the air and upon the grain itself.
If none of your friends has a sourdough starter to share, how best to colonize these yeasts you cannot even see? Actually it’s as simple as remembering where they lurk and what they eat.

Ripe Sourdough Starter From the 'Fridge

Home For a Yeast

Attracting wild yeasts with a flour and water paste is something like attracting your own nest of birds by building them a house. The main difference is that yeasts are gluttonous and don’t know how to go out and find worms, moths or caterpillars. So you have to feed them often, especially while your colony is growing. The other difference is, no matter how light the chirping baby birds may seem, you will not be able to use birds to raise a loaf of bread.

Developing a Practical Sourdough Method

My current advice on sourdough starters comes from combined experience and the teachings of various bakers. I have followed Peter Reinhardt’s and Jeffrey Hamelman’s methods, more or less precisely, for building sourdough starters. During my Advanced Bread course at Johnson & Wales, my group kept and baked with both rye and wheat starters. Perhaps most influential, though, were the big buckets of sourdough starters I saw in bakeries where I worked, kept by bakers either totally ignorant or particularly aware of just how much neglect wild yeasts will tolerate.

Professional baking authors typically instruct their readers to toss out a portion of starter and replenish with fresh flour and water daily, although it is sad throwing out that much flour. The more practical method, of using what starter you need, storing the rest in the refrigerator and replenishing when it gets low, eliminates the problem of waste. Also, you don’t have to spend time feeding your starter on days you don’t plan to bake.

Choosing an Organic Whole Grain Flour

Sourdough starters for bread-making are made from rye or wheat flour. Using a large percentage of rye starter, or experimenting with wheat starters made with varying amounts of water, will produce different distinct varieties of bread.

For simple leavening purposes (making your loaf of bread rise), either rye or wheat will work. It may be easier to get a sourdough culture going using rye flour, but wheat flour may be easier to find.
Certainly, it is best to use whole grain flour rather than refined white flour. Whole grain wheat flour is sold as Whole Wheat Flour, while whole rye flour is usually called Dark Rye.
Organic flours do not contain genetically modified grains, and you may even be able to find a source of organic whole grain flour milled locally from grains grown in your region. Some bakers are enthusiastic enough to buy grain mills and mill their own flour.
At any rate, choose a flour that appeals to you and keep a few pounds on hand as you get your starter going and bake your first loaves of flavorful sourdough bread.

How to Begin

Building a healthy sourdough starter requires from a few days to just around a week of consistent feedings, and minimal simple kitchen tools.

Leave a vent so the yeast can breath

It is important to use a glass, plastic or ceramic container. It is extremely difficult, if not impossible, to develop a sourdough culture in a metal container. I cannot remember why, but I can remember how disappointing it is to feed and feed a starter and to never have it grow. Since you will need to loosely cover the container, it may be easiest to find a 2-quart glass or plastic food storage container with a lid that can be placed over it but not sealed. One other warning regarding the storage container; do not use ‘self-sealing’ plastic wrap to cover the bowl. There is some kind of chemical on the self-sealing surface that effects the health of sourdough. Any kind of spoon or mixing utensil, including your hands, will be fine for making the paste.

Once you have chosen a flour and found a good container, stir together about a cup of flour with enough water to make a thick paste. Place the lid or another loose cover over the container and leave it at room temperature for about 24 hours.

Feed the Starter Regularly Until it is Doubling Between Feedings

Next day, you will not see much, if any, difference in the appearance of the flour paste. That is OK. Remove about half of it and throw it in the compost (or garbage). Add enough flour and water to double the portion of paste that is left. Remember, you will only have to toss out starter for the first few days, so don’t resist.

It is important to add enough fresh flour and water to match the amount of paste you are leaving. That gives the growing yeast plenty of food. Loosely cover the replenished starter and leave for another 24 hours.

Next day, toss out half and add another portion of flour and water to match the amount of paste you have. This time, leave for only 12 hours before repeating the feeding procedure.

After a few days of consistent feedings, your starter will begin to bubble and grow

Continue to toss half and feed the starter with fresh flour and water every 12 hours until it shows signs of life. After 3-5 days you should have a pretty healthy sourdough starter. Soon it will be growing to double its size between feedings, and is ready to use for leavening bread. If you have a clear container, you will see bubbles in the starter. Sprinkle flour on the surface of the starter before leaving it to rise, and you will see cracks in the flour as the starter expands.

Cracked surface of a ripe rye sourdough starter, sprinkled with flour

Naturally Leavened Bread Requires Only Patience

When your starter is healthy and has doubled in size, mix it into a batch of bread dough in place of commercial yeast. Wait long enough and the dough, like your starter, will double. Form loaves, let them double again, and bake.
Sourdough is less consistent in the amount of time it takes to rise, when compared with commercial yeast. The longer rising time, however, gives the dough a chance to develop more complex flavors. If bread does not rise long enough, it may be dense and heavy. Be plenty patient and the bread should turn out good and light.

Between Loaves

When you use your starter to make bread, be sure to reserve a small amount to perpetuate it. A tablespoon or two is usually plenty.
Add fresh flour and water, allow the sourdough to ripen at room temperature until it is nearly doubled, then loosely cover it and store it in the refrigerator until you are ready to bake again.

When using starter directly from the refrigerator, your loaves may take longer to rise. For a faster rise, remove the starter and give it one feeding the day before you plan to bake. This is also a good idea if you go 2-3 weeks between batches of bread.

Always, always remember to keep and replenish a small portion of the starter so that you do not have to start from scratch!