How to Dehydrate or Dry Sourdough Starter to Preserve It

Need a break from baking sourdough? Want to ship starter to a friend, or simply preserve some as backup? Then this post is for you! Let me teach you how to dry sourdough starter. The process is incredibly easy, and results in a compact, living, but dormant starter that keeps for many years. We’ll also cover a few common questions about dehydrated sourdough starter, including how to store, reactivate, and use it. 

What is dry sourdough starter? 

Dry sourdough starter is made by dehydrating wet, active sourdough starter. When done right, the drying process effectively preserves the beneficial bacteria and yeast that makes sourdough bubble and rise. Dry sourdough starter is still very much alive but in a dormant state. Therefore, dry starter requires zero maintenance, lasts even longer, and is easier to store or ship than active wet starter. Dehydrated sourdough starter can be ground into a powder (like coarse, chunky flour) or left in larger flakes or chips.

Why dry or dehydrate sourdough starter?

There are a number of reasons to dehydrate sourdough starter, including:

• Dehydrating sourdough starter is a great way to preserve it and save extra starter as “insurance”. Then if something happens to your wet sourdough starter, you have backup on hand!  
  
  
• Dry sourdough starter is much easier to ship, travel, or move with.
  
  
• It’s an ideal way to share starter with friends or give as a gift, especially since it doesn’t need to be reactivated, fed, or cared for right away. The recipient can tackle it once they’re ready!
  
  
• Some folks dehydrate sourdough starter when they want to take a prolonged break from baking sourdough, such as before going on vacation or when it’s too hot to bake during the summer months. However, keep in mind that most sourdough starters will stay good in the refrigerator for several months, even without feeding it! After a period of neglect, wet starter will develop a layer of dark liquid called hooch, but is generally still alive and usable after a little TLC. Check out this post to see how to revive a neglected sourdough starter.
  
  
• Another reason to dry sourdough starter is to sell it – like we do! We’ve shared little packets of our California Coast organic dehydrated starter with thousands of people all over the country.

Ways to Dry or Dehydrate Sourdough Starter

There are two main ways to dry sourdough starter: air dry at room temperature, or in a food dehydrator. 

However, if you use a food dehydrator, it is imperative to use a machine that offers precise temperature controls. The starter must be kept below 105°F at all times (90-95°F is best) to avoid “cooking” and killing the essential beneficial bacteria or yeast in the starter culture. We use our favorite Excalibur dehydrator that is equipped with a “living foods” ultra-low temperature setting.

To air-dry sourdough starter, choose a location that is fairly cool, very dry, and has good ventilation. Air-drying starter in exceptionally humid climates may be challenging.  

Can I use the oven to dry sourdough starter?

Yes and no. You can set a tray of wet sourdough starter inside the oven as a protected place to air dry, but do NOT turn it on. Again, heat will kill the starter and render it unviable. But if your oven has a convection fan, it can make the perfect cozy spot to air dry sourdough starter without the heat!

Supplies needed

• Active wet sourdough starter
• A baking sheet for air drying, or a low-temperature food dehydrator
• Parchment paper, silicone baking sheet liners, or dehydrator tray liners
• Silicone spatula 
• Storage container

Steps to Dry Sourdough Starter

1) Start with active sourdough starter

For the best results, feed your sourdough starter before drying it. Allow it to reach peak activity (when it has at least doubled in size after feeding, but hasn’t started to deflate yet) before collecting some of the starter to dry. That way, you’re capturing the maximum number of beneficial bacteria and yeast in the starter, resulting in a stronger, more resilient, and successful dried starter culture! You can also dehydrate unfed discard, but the dry sourdough starter will be more sluggish to revive.

If you need any tips on how to feed sourdough starter, visit our starter maintenance guide here. We typically mix ½ cup established starter, ½ cup lukewarm filtered water, and 1 scant cup of flour to feed our starter. Scale up the proportions if you plan to dry a large volume of starter.

2) Spread Thin

Once it reaches peak activity, take some of the wet starter from the container to dry. Unless you no longer want your wet starter, don’t use it all! Reserve some to maintain and use for baking. 

Use a spatula to spread the wet starter out in a thin layer on a baking sheet lined with parchment paper or a silicone baking mat, or on a food dehydrator tray liner. If you don’t have tray liners for your dehydrator, you can use parchment paper. The more thin and evenly you spread it, the more quickly and successfully it will dry. 

3) Dry 

Dry the starter in a food dehydrator set to 105°F or less. To air dry starter, place it in a cool and dry location that has good airflow. Leave the tray uncovered, but away from animal hair or dust if possible. If your oven has a convection fan, put the tray of starter in the cool oven to air dry (oven off, fan on). It should dry even faster in there than sitting out on the counter, and be more protected!

Allow the starter to dehydrate until it is completely dry, brittle, and snaps when bent. The time it takes to fully dehydrate sourdough starter depends on the method you use, how thick you spread it, and the ambient humidity in your kitchen. We usually run our dehydrator on 95°F for about 24 hours.

Once it’s 100% dry, you can break up the dehydrated starter into chips or flakes, or grind it into a powder in a blender or food processor.

How to store dry sourdough starter

Store dehydrated sourdough starter in a cool, dark, dry place inside an airtight container. For example, inside a ziplock bag, small Tupperware container, or jar with a tight-fitting lid within a cupboard or the refrigerator is ideal.  Exposure to moisture, freezing or high heat can reduce the viability. Some folks suggest freezing your starter for long-term storage, but I’ve also heard many stories about that killing starters, so I generally don’t recommend it.

How long does dry sourdough starter last?

A long time! A dry sourdough starter that was dehydrated from a healthy, established starter culture can stay alive (and successfully be reactivated) well over a year or longer after drying. A few of our customers waited nearly three years to reactivate their dry starter, and did so without issue! Some sources say dry sourdough starter essentially lasts “indefinitely”, though the culture can decrease in viability and vigor over time.

How to use dry sourdough starter? (Reactivation)

Unlike dry yeast, you can’t add dry sourdough starter to a recipe in its dry form and expect the bread to rise. It must be reconstituted back into a wet active starter before using it. However, the reactivation process is quite simple! When you’re ready to use it, simply mix the dehydrated starter with flour and water, and give it a few days to regain strength. Follow these easy step-by-step reactivation instructions. 

And that sums how to dehydrate and preserve sourdough starter.

Well, I hope that was helpful! Please let us know if you have any questions or feedback in the comments. There is a printable summary with a place to leave a review below as well. Finally, don’t miss our most popular sourdough recipes below! I think focaccia and ginger molasses cookies are my favorite, if I had to choose… but thank goodness I don’t!

You may also enjoy:

• Basic No-Knead Sourdough Bread Recipe
• Simple Sourdough Focaccia Recipe
• 20 Best Sourdough Add-Ins and Topping Ideas
• Sourdough Starter Feeding & Maintenance Guide
• Herb and Whole Wheat Sourdough Crackers (discard or active starter)
• Sourdough Pancakes recipe (discard or active starter)
• Cinnamon Spiced Sourdough Chocolate Chip Cookies
• Soft & Chewy Sourdough Ginger Molasses Cookies
• Sourdough Cornbread

Print Recipe Pin Recipe

5 from 6 votes

How to Dehydrate (Dry) Sourdough Starter to Preserve It

Come learn how to easily dehydrate sourdough starter, either in a food dehydrator or air-dry. The result is a dry starter that is easy to store, ship or share. Dry sourdough starter is alive but dormant (preserved) and stays good for years to come!

Drying time (varies)1 day d

Course: Sourdough

Keyword: dehydrate sourdough starter, Dehydrated sourdough starter, Dry sourdough starter, preserve sourdough starter

Equipment

• Wet sourdough starter (active)
• Food dehydrator (optional)
• or a baking sheet  (for air drying)
• Parchment paper, silicone baking sheet liners, or dehydrator tray liners
• Silicone spatula 
• Storage container

Instructions

• For the best results, feed your sourdough starter before drying it. Allow it to reach peak activity (when it has at least doubled in size after feeding, but hasn’t started to deflate yet) before collecting some of the starter to dry.
• Once it reaches peak activity, take some of the wet starter from the container. Use a spatula to spread the wet starter out in a thin layer on a baking sheet lined with parchment paper or a silicone baking mat, or on a food dehydrator tray liner. The more thin and evenly you spread it, the more quickly and successfully it will dry. (For reference, about 1 cup of starter will cover a 14 x 14 inch tray)
• Dry the starter in a food dehydrator set to 105°F or less (heat will kill the starter culture) OR set the tray out (uncovered) in a cool, dry and well-ventilated location to air dry. Tip: If your oven has a convection fan, put the tray of starter in the cool oven to air dry (oven off, fan on).
• Allow the starter to dehydrate until it is completely dry, brittle, and snaps when bent. The time it takes to fully dehydrate sourdough starter depends on the method you use, how thick you spread it, and the ambient humidity in your kitchen. We usually run our dehydrator on 95°F for about 24 hours.
• Once it’s 100% dry, you can break up the dehydrated starter into chips or flakes, or grind it into a powder in a blender or food processor.
• Store dehydrated sourdough starter in a cool, dark, dry place inside an airtight container. It should stay viable for many years.
• To use the dry starter, you must reactivate (reconstitute) it back into wet active starter first. Follow these instructions or google "Homestead and Chill reactivate dry starter" to find them.