Can I use my starter straight out of the fridge? This is one of the most common questions I get asked. The short answer is yes you can - but you really shouldn't.
While it may be tempting to bake with a cold inactive starter, if you want to bake delicious sourdough bread consistently it's best not to use your starter directly from the refrigerator.

Sourdough cultures are made up of a community of yeast and bacteria. Through the process of fermentation, these microbes leaven bread and impart both the texture and flavor that makes sourdough bread so delicious. A vigorous, healthy sourdough starter is the foundation of great bread and caring for your starter culture is one of the most important parts of being a sourdough baker.
While you can bake with a starter straight from the refrigerator, the result can be unpredictable and is usually less than ideal. Think of activating your starter as sharpening a knife, it gives the microorganisms in your culture a boost so they are ready for the task at hand, it brings out your starter's best characteristics and helps increase your chances of a great bake.
In this post, I’ll explain how cold temperatures and refrigeration affect your sourdough starter. Why you should activate your starter before using it to bake bread. I'll show you my step-by-step process of “waking my starter up” to get it ready for bread baking. Finally, I’ll talk about a few instances when it’s ok to use your sourdough starter straight from the refrigerator.
How the Refrigerator Affects Your Sourdough Starter
The cold temperature of the refrigerator slows down the metabolic activity and the growth of yeast. However, bacterial activity proceeds at the same pace, which means acid production also continues.
As your starter rises, it metabolizes sugars in the flour that you’ve fed it. If you’ve kept a starter for sometime, you’ll know that it can go through its food source in a matter of hours at room temperature. In the refrigerator, the fermentation process becomes much slower and this food can last a couple of days or even up to a few weeks. This makes the refrigerator a great long term storage method for a mature starter.

Sourdough starter straight from the refrigerator resembles a paste, flat with no bubbles

24 hours after the first feeding, showing signs of fermentation with an even distribution of bubbles throughout
Although they remain active in the refrigerator, lactic acid bacteria don't do as well in the acidic environment encouraged by cold temperatures. While it may seem counterintuitive, highly acidic environments actually discourage lactic acid bacteria from producing byproducts that impart the deep and tangy flavors we love in sourdough, resulting in bread that tastes blander.
If you’re storing your starter in the fridge for long periods, refrigerate it immediately after adding fresh flour. This is when it is least acidic, and will help maintain the depth of flavor of your sourdough starter. (Source: Scientific American)
Why You Shouldn’t Bake Sourdough Bread with Your Starter Straight from the Fridge
The refrigerator essentially puts your sourdough starter in slow motion. This is why it’s not such a great idea to bake bread using a cold sourdough starter.
Using a starter directly from the fridge makes it unpredictable. A mature and active starter usually rises to its peak about 4 to 6 hours after being fed. This correlates closely with the amount of time it takes microbes in your starter to ferment dough. Cold temperatures make yeast too sluggish so it can be difficult to predict how long it will take to make bread rise.
If you’re a beginner it’s especially important to activate your starter first before using it in a recipe. Most sourdough recipes, like my Basic Sourdough Bread Recipe, call for an active sourdough starter and assume that your starter is in a healthy state and is able to make dough rise in about 4 to 6 hours. If your starter is too weak, it will take your dough much longer to rise and you won't be able to follow the time cues given in recipes. This usually results in under-fermented bread that is dense and gummy.

In addition to being more sluggish and weak, a starter stored in the fridge also has the tendency to be more acidic. As a result of your starter not being efficient enough to make bread rise in a reasonable amount of time, the acidity of your starter could cause the gluten in dough to break down. This prevents the formation of gluten bonds that capture carbon dioxide that’s produced by yeast during fermentation. As gluten breaks down the surface of the dough tears as it ferments, preventing it from rising. When this happens the dough will have less oven spring and the resulting bread with be flat and gummy, most bakers call loaves like this a "flying saucer."
How to Prepare Your Starter for Baking Bread to Get the Best Results
For the best results, it’s a good idea to activate your starter first before using it in a recipe!
What You Need
Spatula: I love spatula from OXO because the long handle allows me stir my starter without getting sticky stuff all over my hands. Plus the small head fits into any container and is great for scraping.
Jar: I've used Mason Jars from Ball and Kerr forever, but I've been really liking Weck jars lately since they have a wide mouth with no grooves where dried up starter can build up.
Kitchen scale: This cheap but mighty scale has been a staple in my kitchen since I started making bread. It's only $10 and has never had any issues, well worth the investment. I've tried lots of more expensive scales and this one continues to out perform and outlast them all.
All-purpose flour: I've fed my starter all-purpose flour from Central Milling for the last 4 years. It's an organic flour sold by a company comprised of passionate bakers who really care about the quality of their product. All-purpose is less expensive than bread flour and whole wheat and provides enough nutrition to your starter. You are going to go through so much flour over the life of your starter, all-purpose is an excellent option that will not break the bank. If you can't find Central Milling, use organic all-purpose from King Arthur Flour, Bob's Red Mill or your local mill.
Water: Always use filtered or spring water for your sourdough starter as tap water in the United States has a lot of chemicals that can adversely affect the microorganisms in your starter culture. We've used this Reverse Osmosis System for years and love it! I
Importance of Weighing your Ingredients
Weighing ingredients is more accurate than using volume measurements (cups and tablespoons), especially when you're measuring out such small quantities. The proportion of water and flour (hydration level) used in a sourdough recipe matters a lot to the overall consistency of your dough and bread, so accuracy is important.

Step-by-step Instructions
Day 1: Pull your sourdough starter out of the refrigerator.
Unfed starter | 28 grams | 2 tablespoons |
All-purpose flour | 28 grams | ¼ cup |
Water | 28 grams | 2 tablespoons |
- Add all of the ingredients in a clean jar and mix everything together until completely combined.
- Cover the jar loosely with a lid and place it in a warm spot for 24 hours. Since the yeast are still sluggish, they will take some time to metabolize the fresh flour.
24 hours after the first feeding your starter should look bubbly, well-risen and have an even distribution of bubbles throughout. If your starter is still flat and lifeless, repeat step 1.
Step 2: Test your starter for readiness.
Once your starter begins to show signs of life. Move on to testing it for readiness.
Sourdough starter | 14 grams | 1 tablespoon |
All-purpose flour | 28 grams | ¼ cup |
Water | 28 grams | 2 tablespoons |
- Add all of the ingredients in your jar and mix everything together until completely combined.
- Cover the jar loosely and place a rubber band on your jar to mark the level where your freshly fed starter started. Set the jar in a warm place.
- After about 4 to 6 hours, check whether your starter has doubled.
- Repeat this process once your starter reaches its peak. If your starter rises dependable, in 4 to 6 hours, then it's ready to use for baking!
Day 3: Prepare your sourdough starter for bread baking!
For the best results, feed your starter every time it reaches its peak the day before you want to use it for baking. This strengthens yeast, making them more active and efficient. It also encourages the production of acids with deeper and sweeter flavors.
If I plan to mix my dough in the morning, then I’ll do this the night before. The high percentage of flour and water will ensure that your starter has enough food as it rises overnight.
Sourdough starter | 7 grams | ½ tablespoon |
All-purpose flour | 56 grams | ½ cup |
Water | 56 grams | ¼ cup |
- Add all of the ingredients in your jar and mix everything together until completely combined.
- Cover the jar loosely and set in a warm place.
- Your starter is ready once it has doubled or tripled and will be ready to use up to 8 hours after being fed.
Signs I look for to know my starter is ready for baking:
- An even distribution of bubbles throughout
- Thick consistency
- Sweet aroma that's not too acidic
- Rises predictably and dependably

Why It’s Best to Wait Until Your Starter Has Doubled Before Using It
The easiest way to guarantee consistently good results is to use your starter once it has at least doubled or tripled. Your starter is at its peak when its at its highest level right before it falls or deflates. This is when there is the highest concentration of yeast and when they are the most active and most efficient at fermenting dough.
When It’s OK to Bake with Your Starter from the Fridge
Just like each starter is truly unique, every baker’s experience with sourdough is different! If you’re an experienced baker and are familiar with working with a cold sourdough starter that has been kept in the refrigerator for a long time and you’ve had success, then it’s totally OK to use your starter straight from the refrigerator.
You can also use your starter directly from the fridge if you’re not using your sourdough starter as a leavener. You can use a cold starter on any sourdough discard recipes. Sourdough Irish Soda Bread, Sourdough Biscuits, Sourdough Discard Flatbread and Sourdough Scones use baking soda and baking powder instead of sourdough starter for leavening and are great options if you want to make bread at the last minute and don’t have time to activate your starter.
Questions?
Rye has a much lower protein level than white flour. A sourdough starter made with rye flour can’t form strong gluten bonds, and isn’t able to capture gas formed during fermentation. So although your starter may be active, it may not double or triple.
It’s extremely difficult to kill your starter. Unless it grows mold, your starter is still alive and well. Yeast and lactic acid bacteria in your sourdough starter prevent the species of bacteria that cause spoilage and mold from growing on your culture. If you see any fuzzy growth or any shades of blue, green, pink, or beige on the surface of your starter, then its best to throw it away and start over. By the time you see any discoloration and growth on your starter, it means that the entire culture is infected, it may be unsafe to simply scrape it away.
The number of times you need to feed your starter really depends on your environment and the individual health of your starter. Continue to refresh your starter until it rises predictably before using it in a recipe.
One reason your starter won’t rise may be because your kitchen or environment is too cold. Fermentation occurs at an optimum temperature of 78 to 80 F. Give your starter a boost by keeping it in a warm spot like your microwave oven or your oven off with the light on. I keep my starter in the Brod and Taylor Proofing Box which keeps it at a constant temperature.
After your first feeding out of the refrigerator, allow your starter to ferment for 24 hours, enough time for your microorganisms to wake up and process their food source before repeating the feeding process. This ensures that you won’t deplete the yeast in your starter by discarding it and feeding it too quickly before they have reproduced.
The hydration level of your starter and the type of flour you feed it could also affect its consistency and how it rises. A starter made with whole wheat flour or rye flour could be active and viable but may not rise as high as one that’s made with white flour. A lower hydration starter could also have a thicker consistency that won’t increase in volume as much.
Did you make this recipe? Do you have questions? Let me know!