If you want to know how to make sourdough starter last indefinitely, the secret’s dehydration. Any time you want, you can press the pause button on your bread baking. Just put your starter on hold! So to help you set your starter on autopilot, here’s a recently tested step-by-step dehydration guide.
[editor’s note: this post was updated in April 2019 based on more testing! updated instructions in below post.]
Talk to people about sourdough starters, and expect someone to scare you. “It’s like a pet or a child!” “You’re going to kill it!” “What will happen when you travel for work or pleasure, or you’re in the hospital, or you face some unexpected tragedy in life?”
You’ll hear your starter needs constant care. Someone will say to find a loyal friend you can count on to treat it as his or her own. But all this counsel is unnecessary because here’s the truth: you can take a break from maintaining your sourdough starter any time you want.
The secret is dehydrating your starter.
Why Dehydrate Sourdough Starter
Even if you’re already a fairly low-maintenance sourdough baker and, for example, keep your starter in the fridge and only feed it once a week, you still may run into circumstances that mean you want a lesser load. That’s where dehydration comes in handy.
Dehydrating sourdough starter is the answer to all the questions you didn’t know you’d be asking once you started baking naturally leavened bread.
Questions such as…
- How can I protect my starter when I’m going to be out of the country, traveling for business, caring for a newborn, living through a kitchen renovation or otherwise too busy for a few months to give it any of my mental space?
- My out-of-town friend wants to bake sourdough, but how can I send over some starter? Is there a way to safely ship it in the mail?
- I’m thinking about converting my starter to a different flour, but maybe I should save some in case it goes south. Do I need to keep feeding two jars, or is there a way to preserve some for emergencies?
For all these situations, there’s dehydration. And, best of all, you don’t need fancy equipment, complicated steps or lots of effort to do it.
How to Dehydrate Sourdough Starter
- Start with an active, fed, lively starter. I pulled mine straight out of the fridge, fed it and gave it enough time to double.
- Spread it on a parchment-lined baking sheet. Top a baking sheet with parchment paper. Then, use a spoon to scoop out your active starter and spread it out into a thin layer onto the paper.
- Wait until it’s dry. Set the baking sheet somewhere out of the way and give it time (mine took three days) to completely, totally dry. You don’t want there to be any tackiness or even slight moisture.
- Break the starter into pieces and store them. Once the starter’s totally dry, it should break apart like peppermint bark into irregular pieces. Place this pieces in an airtight container, close it and you’re done. The starter will keep indefinitely.
How to Rehydrate Starter
When the time comes that you’re ready to reawaken your starter, whether that’s a month from now or two years from now, here’s what to do:
- Combine one ounce starter and two ounces warm water. In a clean mason jar or other container, measure out exactly one ounce of your dehydrated sourdough starter. Add in two ounces of warm water. Stir together.
- Stir occasionally for about three hours. For the next several hours, give the mixture a stir every once in a while. Keep doing this until the starter starts to reabsorb liquid and get mixed.
- Add in equal parts flour and water. Assuming you are working with 100% hydration starter (what I use), stir in equal parts flour (the same type of flour that was used in the original starter) and water to your mixture. Use a rubber band to mark how high the mixture is in the jar.
- If the mixture doubles within several hours, you’re ready! From here on out, you can just return to your normal sourdough routine, whatever suits you.
- If the mixture doesn’t rise much within several hours, discard half and refeed equal parts water and flour. Repeat until you get to a point where the mixture doubles.
- [edit! after testing this method again in April 2019, I realized some starters will still be sluggish after all the above steps. In these cases, the following next steps should bring it back to life.] Bonus troubleshooting method: Separate out one ounce of your starter into a jar and combine it with two ounces each of water and flour.
- For the next seven to eight hours, every two to three hours, add another half an ounce of flour and half an ounce of water to the starter, without discarding anything. You should see some activity, even small, each time to feed the starter.
- After you’ve done these mini-feedings at least three times, leave your starter alone for 18-24 hours. At this point, you should still major growth.