Sourdough Starter Instructions


Before You Begin

  • Your sourdough starter has been shipped in a dehydrated state. The starter is shelf-stable and can be used any time in the next few months. Store the starter in a cool dry place.

  • Whenever possible, use filtered non-chlorinated water when feeding your sourdough starter.

  • Use the same kind of flour as the starter was grown in (white, whole wheat, rye, etc.) to activate this starter. Once your starter has been fully activated, you can feed the starter and bake with a different variety of flour if desired.

  • If you are culturing multiple products (e.g., different varieties of yogurt, buttermilk, kefir, sourdough, kombucha, etc.) or baking with commercial yeast, be sure to keep a distance of at least several feet between cultures so they don’t cross-contaminate each other. Over time, cross-contamination can weaken the cultures.


Activating the Sourdough Starter

  • Place the contents of the package into a clean quart (or larger) wide-mouth canning jar or similar container.

  • Add 1/4 cup tepid (room temperature) water and mix well. Add 1/4 cup flour and stir vigorously.  Be sure to incorporate a significant amount of air into the mixture.

  • Cover loosely. (A towel secured with a rubber band, or a plastic lid just set on top but not secured, will work well.) Place in a warm area (70° to 85°F) for approximately 12 to 18 hours. The warmer the spot, the more quickly the starter will activate. An oven with just the pilot light or oven light turned on can work well as will a high shelf or a food dehydrator with a low temperature setting. Be sure to verify that the spot where your sourdough culture is sitting is within the 70° to 85°F temperature range. Temperatures outside that range can be problematic for activating the culture and can even damage or kill the culture.

  • Mix in 1/2 cup water and scant 1/2 cup flour. Be sure to incorporate a significant amount of air into the mixture. Cover and return to the warm spot for 12 hours. Be sure to use a sufficiently sized container and place a cloth or paper towel under the container as active sourdough starter may bubble over.

  • Discard all but 1/2 cup of the flour and water mixture. (See our sourdough pancake recipe for a way to use extra discarded sourdough starter). Mix in 1/2 cup water and a little less than one cup flour. Repeat this process every 12 hours until the mixture becomes light and bubbly. If the mixture is kept quite warm, this process may be concluded within the first several days. For cooler spots, it may take several more days to complete the process. It is common for sourdough starter to take 3 to 7 days to activate.

  • Once the starter is bubbling reliably within several hours of being fed, feed the starter for two more cycles then cover loosely with a lid and place it in the refrigerator until you are ready to bake with it. The lid may be tightened once the mixture becomes dormant and minimal carbon dioxide is being produced.

Making Fresh Starter

  • "Fresh sourdough starter" is a term often used in recipes to refer to recently fed, active sourdough starter.

  • Refrigeration places the sourdough starter in a state of hibernation which allows a starter to go at least a week without being fed, but also renders the yeast temporarily ineffective as a leavening agent. To bring the starter out of cold-induced hibernation, the sourdough starter should be fed at least three times to fully activate the yeast prior to using the starter for a baking project.  

  • Start the fresh starter process by removing 1/4 cup of sourdough starter from the refrigerator. (If a liquid layer has developed on top of your starter, pour off the liquid layer first.)  

  • If using a kitchen scale: Add flour and water in amounts equal (by weight) to the amount of starter. For example, for 50 grams of sourdough starter, mix in 50 grams of flour and 50 grams of water. The scale method is preferred due to significant differences in flour density.

  • If using measuring cups: Use 1 part sourdough starter to 1 part water to a little less than 2 parts flour. For example, if you are starting with 1/4 cup of starter from the refrigerator, mix in 1/4 cup water and a scant 1/2 cup flour.  

  • Cover and allow the mixture to sit for 4 to 12 hours until it has “proofed” (become active). The amount of time will depend primarily on the nature of the specific sourdough starter and room temperature. Sourdough that has proofed becomes light and bubbly. The gas created often causes the sourdough starter to expand in size so be sure to use a sufficiently sized jar and set the jar on a paper towel to protect the surrounding surfaces in case the starter bubbles over. If the sourdough does not become bubbly within 12 hours, proceed with the next feeding.

  • Repeat this process at least two more times. For each feeding use equal amounts of starter, flour, and water by weight, or use the measuring cup ratios above. If you make too much sourdough starter during this process, prior to the next feeding some starter can be discarded or set aside to make sourdough pancakes.

  • If at any point during this process a liquid layer develops on the sourdough starter, pour off the liquid layer prior to the next feeding. The liquid layer is generally a sign the starter needs to be fed more often so feedings should be moved closer together (i.e., feed the starter every 8 hours instead of 12 hours, etc.).

  • Once the starter has been fed for at least three cycles and is bubbling reliably within several hours of being fed, measure out the portion needed for the recipe.  

  • Be sure to add some of the extra fresh starter back to your master sourdough starter in the refrigerator. This process feeds the sourdough starter for the week (see below).

Feeding the Sourdough Starter

For best results, feed the refrigerated sourdough starter weekly. The above process for making fresh starter will feed your master starter for the week. If you do not make fresh starter during a given week, use the following process to feed your master starter.

  • Remove the starter from the refrigerator. If a layer of liquid has developed on top of the starter culture, simply pour it off.

  • Discard all but about 1/4 cup of starter. Add equal amounts (by weight) of flour and water. (If using measuring cups, use 1/4 cup water and a scant 1/2 cup flour.) Mix vigorously to incorporate air.

  • Cover loosely and allow the starter to proof at room temperature for several hours. Return the starter to the refrigerator at the conclusion of the proofing process.


Click here for extensive troubleshooting information.

  • There are generally three factors that contribute to sourdough rising well and resulting in light fluffy bread:

    • Be sure your yeast is fully active before baking. If your sourdough starter has been stored in the fridge, it has been living in a dormant state. Plan to feed the culture at least three times, 8 to 12 hours apart, prior to baking. 

    • Knead your dough well to activate the gluten. It is very important to allow the gluten to fully develop so thoroughly kneading the dough is a critical step. If you are kneading by hand, plan for a minimum of 20 minutes. (You can take breaks, such as kneading for 5 to 10 minutes at a time.) If you are using a mixer to knead, check the dough often to ensure it's not overheating (which can damage the yeast) and stop the process once the gluten is well developed. While there isn't any danger of over-kneading when kneading by hand, mixers can abuse the dough if not watched. To determine whether the gluten is adequately developed, perform the "window pane test": take a piece of dough and stretch it between your fingers. If the gluten is sufficiently developed, the dough should stretch thin — so you can see light through it — without the dough breaking. If it breaks before it can be stretched thin, keep kneading.

    • Plan for a long proofing (rise) period. As a natural yeast, sourdough tends to take significantly longer to rise than bread made with commercial yeast. Timing is dependent on the specific starter and conditions in your home so until you have determined the best rise period for your particular starter, plan for a 3- to 12-hour rise period. (If you desire more sour bread, plan for 12 to 24 hours).

Basic Sourdough Bread

Related Articles & Recipes:


Related Products:

Sourdough Starters

Free eBook Library Access & Weekly Newsletter

Sign up today for free access to our entire library of easy to follow eBooks on creating cultured foods at home, including Lacto-Fermentation, Kombucha, Kefir, Yogurt, Sourdough, and Cheesemaking.
  • Library of eBooks for making your own cultured foods
  • Weekly newsletter filled with tips & tricks
  • Expert advice articles, recipes, and how-to videos
  • Join 180,000+ other health-conscious readers
  • We never share your information!
first name last name email address