Sourdough Starters 101

There are few things more exciting and rewarding then making your own, fresh, artisan bread from a natural sourdough starter. Commonly misunderstood, artisan baking with the use of a sourdough starter is a dying art, relegated to a drawer full of failed and labor intensive recipes never to be attempted again.

But fear not; this article will jump start your understanding of not only the underlying chemistry of sourdough starters, but also how to make and maintain your very own.

What Is A Sourdough Starter?

A sourdough starter is nothing more than a mixture of water and flour that contains natural occurring yeast. Back before the advent of Active Dry Yeast and Instant Dry Yeast, this is how bakers, even at home, made their fresh breads, often daily.

Bread baking as a whole has really lost popularity, with people being resigned to purchasing mediocre bread at their local supermarket if they’re not lucky enough to have a neighborhood bake shop. And even then, the mark-up is incredible.

Just to put the price into perspective, I purchased a 50# bag of bread flour at Costco the other day for a total of $12.95. If you buy four or five loaves of artisan sourdough from your local baker, chances are that you’ve already paid for that 50# sack.

What Gives Sourdough Its Unique Flavor?

The unique sour flavor comes from the bacteria that love to live in sourdough starters. Much like yeast, these bacteria will consume the sugars present in the flour, and in turn give off carbon dioxide (which helps your bread to rise), as well as acid.

The two most common acids that are produced by these bacteria are lactic acid and acetic acid (the same form of acid found in vinegar). It is the acetic acid that gives sourdough its signature sour flavor, and the lactic acid helps balance the acetic’s harsh bite. Without the lactic acid being present, the acetic acid will take over the flavor of the sourdough.

But if the thought of having bacteria living in your sourdough starter scares you, don’t fret. These bacteria are harmless and very territorial; the acidic environment they create is uninhabitable for most other forms of bacteria. Not to mention that the finished internal temperature for most bread is around 195 F, plenty hot to kill any harmful bacteria that may be present.

What Are The Different Types Of Sourdough Starters?

There are three main types of sourdough starter which I’ve listed below. They all work fine, and which one you use will depend more on your own personal preference and how often you want to use your sourdough starter for bread making.

Biga

A biga is basically a stiff sourdough starter with a 50-60% water content by weight. This is favored by bakers who don’t bake more then once or twice a week, because it takes longer for the Biga to reach its peak fermentation stage, especially when retarded in the refrigerator. Although you can start a Biga with natural yeast from the skins of fruit or from rye flour, because of its stiff quality, it is much more difficult to get this form of sourdough starter going.

If you still want to work with a Biga starter, I would recommend starting a Poolish, (see below), and then once it is active, add more flour to reduce the water content to the appropriate 50-60%.

Poolish

A Poolish starter is similar to the Biga except that it has a higher water content; in fact, its a straight 1:1 ratio by weight. So for every 100 grams of flour, you will also add 100 grams of water.

The easiest way to inoculate this form of starter with yeast is the addition of fruit peels (apples, grapes, pear, etc).

Scrap Dough

A Scrap Dough Starter is just how it sounds; after a bread dough is kneaded and before it is left to proof, a small piece of dough is cut off and reserved for the next batch of bread. This is an old school technique favored by cooks who use to bake fresh bread every day, before the advent of supermarkets.

How Do I Make My Own Sourdough Starter?

If you’re interested in making your very own sourdough starter, just follow this simple recipe below. This recipe will be enough to make about four medium sized sourdough loaves with some starter left over.

You will need:

• 800g bread flour
• 800g warm water
• The peels of two apples
• A 2ft section of cheese cloth

1. Mix bread flour and warm water together thoroughly with either a wooden spoon or the dough hook attachment of your KitchenAid, (always mix on the second speed).
2. Once the flour and water are evenly combined, resembling an extremely loose dough, place in a container large enough to allow the starter to at least double in size.
3. Place the apple peels in a cheesecloth pouch and shove down in the center of the sourdough starter. The peels can be added directly to the starter without the cheesecloth, but you will eventually have to separate the peels from the starter, which can be a pain.
4. Cover the container with a clean towel and place it in a warm but not hot place in your kitchen. You should start to see some initial activity in about 3-5 days.
5. Once your starter is bubbling and has doubled in size, remove half from the container (about 800g) and replace with 400g water and 400g bread flour.
6. Let sit out at room temperature overnight.
7. If in the next day it has doubled in size and seems very active, then repeat step #5. After feeding, you can now cover your starter with a lid and place in your refrigerator for storage.

Feeding Schedule

If you store your Poolish Sourdough Starter in the fridge once it’s active, you will need to feed it about every 3-7 days by removing half of the starter and replacing it with a equal parts water and flour.

If you starter seems to become “inactive” you can usually revive it by the same process as above, and letting it sit out at room temperature overnight.

OK, So I’ve Made A Starter, Now What?

Stay tuned for our the next podcast episode and blog post where we’ll have an in depth discussion on how to take your active sourdough starter and use it to bake your very own artisan sourdough loaf.

For more information about sourdough starters and pre-ferments, listen to FCS Eisode 18| Sourdough Starters and Pre-Ferments.