Baking Journal
How to Wake Up a Refrigerated Sourdough Starter
A step-by-step plan for reviving a refrigerated sourdough starter, including feeding ratios and signs of readiness.
A starter kept in the refrigerator is usually slower than one fed regularly at room temperature. Give it time to warm up and build activity before you rely on it to raise bread. The exact number of feedings depends on how long it has been chilled and how vigorous it was before storage.
Start one or two days before baking
Take the jar from the refrigerator and inspect it. A layer of grayish liquid can form on an unfed starter; it is often called hooch. If there is no unusual growth or foul odor, stir it in or pour it off according to your preference, then proceed with a measured feeding. If you see fuzzy mold or pink or orange discoloration, discard the starter rather than trying to revive it.
For a typical equal-parts-by-weight feeding, keep 50 grams of starter and mix in 50 grams each of water and flour. Use a clean container with room for expansion. Scrape down the sides, cover loosely, and mark the starting level with a rubber band. A scale makes the ratio repeatable; volume measures of flour and water are not equal by weight.
Watch for activity before feeding again
Leave the starter at a comfortable room temperature and look for bubbles and expansion. A refrigerated starter may take longer to respond than a room-temperature one. When it has risen and shows bubbles, feed it again. King Arthur Baking’s guidance for a sluggish starter is to retain a measured amount, feed with flour and water, and repeat once it becomes active.
If you plan to bake soon, a useful routine is to feed the starter the evening before, then feed again the next day. Time the final feeding so the starter is near its peak when you mix the dough. In a warm kitchen it may peak faster; in a cool room, it can take longer. Use the starter’s height and bubble pattern as your main guide.
How to tell it is ready to use
- It has risen substantially after feeding, often to about double its original volume.
- There are bubbles throughout, not only on the top.
- The top is domed or just beginning to flatten as it reaches its peak.
- The aroma is pleasantly tangy and yeasty, without mold or a rotten smell.
King Arthur Baking notes that a healthy starter often doubles within roughly six to eight hours after feeding, but that timing varies with kitchen temperature, flour, and starter condition. Do not treat the clock as a guarantee. If it barely rises, feed it again and wait until it can expand predictably.
If it stays sluggish
Keep feeding at room temperature and give it more time between feedings so it can consume the food. Use a straight-sided jar and a rubber-band marker to see whether it is rising. A cool kitchen can slow fermentation; place the jar in a comfortably warm spot, away from direct heat. If you are unsure whether it is active enough for a full sourdough loaf, try a recipe that includes a small amount of commercial yeast as extra lift while the culture recovers.
Plan the amount you need
Check the recipe before building the starter so you do not use all of it. Measure the amount needed for the dough, then keep some back to feed and maintain. If the recipe needs more starter than you have, build up the quantity over multiple feedings rather than taking an unripe starter straight from the refrigerator.
For a first bake after refreshing, choose a recipe you know and record the feeding time, room temperature, and peak. Our bulk fermentation guide can help you judge the dough after mixing. Browse all our Bread articles for more sourdough and loaf techniques.