Making Sourdough: Preparation-Care-Tips

Jump to recipe
Fermented Sour dough in jar with bread

Creating a quality Sourdough at home is quite simple. All you need are water and flour, along with a few days for it to become ready for feeding repeatedly. With the proper care, it can last for many years! My sourdough starters have now been thriving for several years.

Optional, but very helpful: San Francisco Sour Dough cultures you can buy on here on Amazon

Flour: Whole grain or unbleached all purpose flour (whole grain or rye flour works better starting out)

Water: Lukewarm filtered or bottled water (not tap water)

A clean glass jar with lid, or bowl (1-liter capacity works well)

Always use clean utensils when handling your starter to prevent introducing unwanted bacteria or mold.

A word about Flour:

Use Quality Ingredients: Use unbleached all-purpose or whole grain flours (King Arthur) for better results across different recipes

1. Rye sourdough for breads with a high rye content

2. Wheat sourdough for breads and rolls with a high wheat content

3. Spelt sourdough for spelt breads and rolls

It is preferable to use Rye or Whole Wheat flour the very first time. You can later replace it with white all purpose flour.

There is also the possibility to make a mixed sourdough starter, or to re-feed your existing one. To do this, take half rye flour and half wheat flour.

Wheat Sourdough: The wheat sourdough is made in principle the same way as the Rye or Spelt sour dough, except with wheat flour add a little more flour than water. It can be dried or frozen in the same way as the Rye ASG Anstellgut (see below). Sourdough can also be made from Spelt flour. When making it, use 1/2 cup (50 g) flour and 40 g water. Even later when feeding, it always gets a little more flour than water, otherwise it’ll becomes very liquid.

ASG (Anstellgut) explained: When recipes talk about ASG, it’s always about your Starter in the fridge. It only becomes sourdough when you mix it with flour and water and let it rise for 4-12 hours at room temperature.

I use a glass preserving jar with a lid that rests loosely on top for my sourdough preparation; a screw-top jar is also effective. A regular knife is the simplest tool to mix the dough. While freshly ground flour is best for this process, any unbleached flour from the store will work too. It’s advisable to add the water first, followed by the flour, and then mix it together using the knife.

flour and water
You’ll need 3/4 cup of all purpose flour and 1/2 cup of water. Also a glass jar with lid

It is completely sufficient to leave the batch at normal room temperature and it should be ready in 4-5 days.

Day 1: Mix 3/4 cup flour with 1/2 cup water, leave to rest in a bowl with a loose lid for 12 hours. Then stir once and let stand for another 12 hours.

Preparing sour dough by adding flour and water
Preparing sour dough by adding flour and water. Before fermentation

Day 2: After a total of 24 hours, “feed” the sourdough with 3/4 cup flour and 1/2 cup water. Stir well and let rise for another 24 hours.

Day 3: After 24 hours, remove 1/2 cup from the starter dough. Feed again with 3/4 of flour and 1/2 cup of water. Let stand for 24 hours. The fermenting should start and some bubbles will form.The leftovers can simply be added to bread dough and baked for aroma.

Day 4: After another 24 hours, remove 1/2 cup of dough, then feed the sourdough with 3/4 cup flour and 1/2 cup water. Stir well and let rise for another 24 hours.

Day 5: After 24 hours, remove 1/2 cup from the dough again and feed with 3/4 cup flour and 1/2 cup water. Stir well and let rise for another 24 hours.

Bubbles are forming on Sourdough
The fermenting should start and some bubbles will form

Day 6: After 24 hours, remove 1/2 cup from the dough again and feed with 3/4 cup flour and 1/2 cup water, stir well and let rise for another 24 hours. If your dough has not formed bubbles yet, feed it with more flour and keep it warm. Around 82 F (28 C) is ideal, I wouldn’t go above 90 F (32 C). This is possible, for example next to a heater or in the oven with the light on (check first)

Day 7: Now the sourdough, the so-called ASG is ready. You can store 3/4 cup in a mason jar (or screw-top jar) in the fridge. Use the rest for your first sourdough bread.

Create Backup Starters: If possible, create dried or frozen backups of your sourdough. This way, you can revive them later if needed (see below under Preserving).

At this point, your sourdough should be ready. The bubbles you observe in the jar indicate that it has developed leaven, which will help your bread rise naturally without relying on commercial yeast. You will use 1/2 to 3/4 cup of fermented sourdough to bake one loaf of bread. However, I still suggest incorporating 1/4 teaspoon of active dry yeast during the initial round of baking to boost the rise. By the second batch, your sourdough should be more robust, making additional yeast unnecessary.

Recipes: One of my most sought-after bread recipes is the German Crusty Bread (see recipe below) and the French Baguette. When making your bread dough, incorporate approximately 1/2 to 3/4 cups of the fermented sourdough per loaf.

The ASG (Anstellgut) should usually be fed 1 time every 10 to 14 days. To feed, take 1/2 cup from the batch in the refrigerator and mix it with 1/2 cup water and 3/4 cup flour. Leave this mixture on the counter until it has doubled in size, then it goes back into the refrigerator. Fermented sourdough has very different strengths, sometimes it can take 3-4 hours for some, others need 6 to 12 hours.

Fermented Sourdough with rustic breads on kitchen counter

When baking multiple loaves of bread, you’ll require a greater quantity of sourdough. To prepare your sourdough, you can increase the amount of water and flour during feeding several hours in advance

When making no-knead Bauernbrot (crusty German Bread), follow the recipe and add sourdough to the water and flour. Combine all other ingredients. Keep the mixture on the counter overnight (17 to 22 hrs) before baking.

Going on vacation? My Active Sourdough Starter (ASG) can last up to 3 weeks in the fridge without needing a feed. Before heading out for an extended period, I give it a feeding the day prior. I also use more flour than water to keep it quite firm. Upon my return, it may appear a bit limp, and there might be liquid or a hard crust on its surface, along with an unusual smell. As long as there’s no mold present, it’s still viable—just hungry! You can remove any firm crusts; everything else can simply be mixed in during the next feeding. After that, you might need to feed it for two consecutive days and leave it out so that it revives properly.

When you first begin making sourdough, the fermentation process is quite minimal at the outset. It’s advisable to use active dry yeast when you start baking bread. As your sourdough ages, its quality improves, and its leavening ability increases. Some of the finest traditional bakeries have sourdough starters that are decades old. The key factor for success is consistent feeding.

For a pure sourdough bread, it is necessary to have a particularly active sourdough. To do this, refresh the ASG 1-2 times, let it stand until it has doubled in size and make the sourdough with this active ASG. If you want a properly acidified sourdough bread, let your sourdoughs rise at room temperature.

If your starter develops mold or if you’re away for an extended period, you have the option to freeze or dry a portion of the sourdough (details provided below).

Freeze: Place the jar with the ASG into the freezer. Allow to thaw to revive, and feed once with 2 teaspoons of flour and a little water. Let stand for a few hours until the sourdough shows bubbles. Then put it back in the fridge.

Drying: To do this, feed the ASG with 200 g flour and 200 g water, let stand for 24 hours. Line a baking sheet with baking paper and spread the sourdough thinly on it. Let the sourdough air dry on a tray for 2-3 days. Then break into small pieces and place into a screw-top jar.

Drying has the advantage that you have a so-called “backup” of your sourdough at all times. I make a new backup of the current sourdough every year, because it gets better from year to year. It happened to me once, I prepared the ASG for the bread dough, and processed it without taking any of it to keep. I had to start over, which took a very long time. Now I just take a few flakes from my backup, mix them with water and let them stand for a while. Then feed again with 3/4 cup flour and 1/2 cup of water and my new sourdough is ready. The dried sourdough can also be finely ground and added directly to the dough if that’s what the recipe says.

Exclude the yeast when using your 1/2 cup of sourdough to make the dough for baking bread.

Be Patient & Experiment! Sourdough baking often involves trial and error. Don’t be discouraged by less than perfect outcomes at first!