How to Activate a Dried Sourdough Culture

Before there was yeast, there was sourdough. For thousands of years, this is how people made bread. Pioneers used sourdough, French bakers used sourdough. If you wanted bread, you had to use sourdough.

Nowadays commercial yeast has mostly taken over and is easy and accessible to everyone, but you will never get the depth of flavor with yeast that you will get with sourdough.

I have been without a starter for several years, and want to get back into artisan sourdough baking, so I bought a few sourdough starters from sourdo.com (I know, who buys more than one starter? Well, I did, to save shipping costs and because I have a tendency to overdo).

There are two other ways to get starter that are cheaper: you can make your own or you can get some from a friend. You create your own starter using wild yeasts from the air where you live (but this can be tricky and isn’t foolproof). Starter requires feeding, and there is always extra starter being tossed due to the nature of feeding, so anyone with an active starter should be more than happy to share (that is really the simplest and most foolproof way).

I wanted something special. So I bought two Italian strains and a French strain instead of making my own. I am starting with the French strain, because it is supposed to be milder and my stomach didn’t like the South African strain I bought and activated 5 years ago. I have also used an Oregon Trail, a gift from a friend about 12 years ago, and a King Arthur Flour catalog starter. My favorite of the three was Oregon Trail. Hopefully the French starter turns out well!

I sort of followed the activation instructions that came with the package. Luckily starter only has to be activated once. The first thing I had to do was make a proofing box that would get up to 90 degrees. Since I didn’t want to spend $150, I grabbed my seed starting mat and thermostat, as well as a drying rack and a plastic container and made my own.

I set the thermostat to 90 degrees, but it only got up to 85. It would be good enough. My house is in the sixties at night so it would be much warmer than that.

Pull out your supplies for mixing the first starter: wide mouth canning jar, trusty digital food scale, filtered water (though tap water works too), all-purpose flour, plastic spatula, and – of course – dried starter pack.

This is where I deviate from the instructions again: the instructions tell you to measure your ingredients, but when it comes to flour, it is better to weigh them. And the amount and hydration (baker speak for flour/water ratio) really doesn’t change whether or not the starter will activate. I like a 100% hydration… a wet, loose starter. Some people prefer a 50% hydration, and it is really up to you so you can do what you like.

Place the canning jar on the scale and zero it out.

Pour 100g water into the jar.

Zero out the scale.

Pour 100g flour into the jar.

Pour the dried starter into the jar.

Stir with plastic spatula. It will be pretty stiff at this point. That is okay.

Cover loosely and place in proofing box for 24 hours.

It should have doubled in size at 12-14 hours. It will grow and then fall if you follow the instructions and feed it at the end of 24 hours. I think it would be safe to feed it again as soon as it has doubled in size, but I waited 24 hours just to see what would happen.

This activated starter looks completely different from the day before. It is no longer just flour and water; it is flour and water and yeast and bacteria. The bubbles are a sign of an active starter.

Maintain your Starter

Now feed it normally, keep it on the kitchen counter, and start a daily feeding regimen. Put equal parts (by weight) flour and water in a new canning jar (4 ounces works for me because I can measure 1/2 cup water), add some starter (I just pour it in and eyeball it, but I like to include somewhere beteeen 1/2 cup and 1 cup starter), and cover it loosely.

After about 3 days of daily feedings, your starter will be ready to cook with.

Fully active starter bacteria will eat through most of the flour within 6-8 hours (longer if your kitchen is colder, such as in the winter), but it isn’t necessary to feed it that often all the time. Feeding it daily and storing it at room temperature will keep it active.

You can store starter in the fridge as well, if you aren’t using it as often. Feed it weekly (but keep it on the counter at least 2 hours after every feeding) and bring it out for daily feedings 3 days before you want to use it, to reactivate it.

What is important is to create a levain out of active starter 6-8 hours before you cook with sourdough. Most recipes will include this step. You will create a levain and then feed your starter and have two bowls/jars: one to use in your recipe and one to save for next time.

If you cook with all the starter you have in your house, you will be out of starter! Don’t do that; you will be sorry.

That is about it for activating your starter. Make many yummy sourdough things!