You can simply dry sourdough and store it for a long time. We will introduce you to three methods of preserving sourdough: by crumbling, drying and freezing.
You only have to prepare sourdough once and can then “feed” it again and again with flour and water and thus multiply it. This makes it last forever. The sourdough contains microorganisms (such as lactic acid bacteria and yeast) that form during the fermentation process and make the dough slightly acidic. However, if you don’t bake regularly or want to send the sourdough to friends or relatives, you can preserve the sourdough by drying it. The shelf life of the sourdough varies depending on the method, ranging from three months to several years.
For each of the three methods, you must first prepare a sourdough. You can find instructions here: Prepare the sourdough. We strongly recommend that you buy the ingredients in organic quality. Among other things, you avoid residues of chemical-synthetic pesticides and support ecological agriculture.
Method: Crumble sourdough
The first method is the “crumbling” and subsequent drying of leaven:
Pour your prepared sourdough into a bowl.
Gradually add the flour and mix everything together with a wooden spoon. Use enough flour so that the dough is only slightly moist and crumbs can form.
Gradually rub the dough between your palms. This creates crumbs. Do the same with the entire dough.
It is best to spread the crumbs on a baking sheet and let them dry for several hours. This way you prevent mold.
Fill the so-called Krümelsauer into a lockable screw-top jar. You should only close the jar loosely or drill a hole in it if the dough continues to ferment a little. Alternatively, use a cloth bag. The dried sourdough can be stored in the refrigerator for about three months.
To use the dough again, add enough water to the crumbs until it becomes a paste. Store the dough at room temperature for about 2 to 8 hours. It is then activated again and can be processed further.
Method: Dry sourdough as flakes or powder
The second method involves making flakes or powder from the sourdough:
Spread the sourdough thinly on half of a sheet of baking paper and fold it over. If you have more dough, use a second sheet of baking paper.
Allow the sourdough to dry at room temperature. This takes about a day or two. The dough needs to be really dry, otherwise mold can form.
Dried, sourdough is lighter in color, cracks, and breaks easily when touched.
Note: You can usually reuse the parchment paper. To do this, carefully peel off the dry sourdough so that the baking paper does not tear. Or you can use a sustainable baking paper alternative.
Break off small pieces of the dried sourdough. Now you have two options:
For tiles: Place the small pieces in a sealable container, cloth bag, or paper bag.
For powder: grind the small dividers into powder with a mortar or grinder.
Dried sourdough lasts for several years. You can store it in the fridge or at room temperature in a dark place (for example, in the pantry).
To reactivate the leaven, you need to add water and flour. First add the same amount of water to the dried dough (ratio 1:1). If he starts blistering at room temperature, you can “feed” him with more water and flour. This can take several hours.
Note: Since most microorganisms die off during drying, the sourdough may not always start to ferment. This is always the case when there are no or no longer sufficient microorganisms in the dough.
Method: Sourdough Freezing
Pour your sourdough into a sealable container that is freezer-safe. Alternatively, you can fill the batter into an ice cube tray. Place the dough in your freezer or freezer compartment.
Freezing disrupts the fermenting properties of sourdough, as some of the microorganisms die off. So give the dough 1-3 days after defrosting to recover slowly. You can add some flour and water and activate it at room temperature. You can then feed him more flour and water.