Sourdough starter troubleshooting, part 2: Can this starter be saved?

In our first sourdough starter troubleshooting post we tackled sourdough starter viability, and what will and won’t cause your starter’s demise. We also found out what a spoiled starter looks like, and how to know when it’s time to throw it out and start over.

Today we’ll take on the thorny question of whether it’s worthwhile to try to revive an old but struggling starter — or if it’s best to start over.

Sourdough starter: a miracle in the making

Creating your own starter from scratch is exciting and even a little magical; for details, see our step-by-step guide to creating a sourdough starter.

Simply mixing flour and water allows friendly bacteria and wild yeast to join forces and establish a balanced ecosystem that is able to impart great flavor and rise to your sourdough baking.

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

During the 6 to 10 days that it takes to get your starter up and running, it’s a little more vulnerable to bacterial intruders and mold because it hasn’t yet developed the defenses of a mature starter. But once fully developed, a well-maintained starter will readily fend off unwanted invaders and is very unlikely to spoil.

Reviving a neglected starter vs starting a new one

What if you inherited an old starter from your grandma and it’s looking a little like it might be at death’s door?

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Sourdough authorities argue that there’s nothing sacred about an old starter; a freshly developed “mature” starter will impart just as much flavor and rise to your bread.

Starting over with a new starter will get you back to baking great sourdough bread in a little over a week. So why take on the unpredictable task of trying to resurrect a sickly starter?

Common sourdough wisdom says that it will take just as long to revive a severely neglected starter as it will to create a new one. But is this always true? Click To Tweet

And is it even possible to thoroughly revive a starter that’s sorely neglected?

Let’s find out.

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Starter showing any mold (or exhibiting an orange or pink streak) should be thrown away. But dark-colored “hooch” (the liquid sitting atop a neglected starter) isn’t a sign of danger.

I start with two very neglected starters. Both starters (one all-purpose, one whole wheat) had been well-maintained until they were left at room temperature for a full month without being fed.

Why test both a white and a whole wheat starter? Starters can be maintained with all different types of flour, so I wanted to see if a whole wheat starter responded in the same way as a starter fed with all-purpose flour.

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Starter made with all-purpose flour

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Starter made with whole wheat flour

I pour the dark hooch off the neglected starters, and feed them following the feeding schedule called for in our sourdough starter recipe.

The revived starters smell a little “off” at first, but not awful; think vinegary sour, with a slightly unpleasant edge. Within four days they’re rising well and have a nice, mildly tangy aroma. My theory is that both the acidity and the maturity of the neglected starters helps them fight off unwanted bacteria at the beginning of the process, which might allow for a faster return to a healthy and balanced starter.

Sourdough Starter Troubleshooting, part 2 via @kingarthurflour

Newly created starter

By way of comparison, I also begin a starter from scratch. My brand-new starter is able to keep up in terms of rise. However, after four days it still smells a little funky and doesn’t seem quite ready for baking bread.

Putting the starters to the test: Test bake #1

On Day 4 (after only four feedings) I bake Naturally Leavened Sourdough Bread using my revived starters (which I mix together for the test), and my regularly well-maintained starters.

Sourdough Starter Troubleshooting, part 2 via @kingarthurflourSourdough Starter Troubleshooting, part 2 via @kingarthurflourThe results are a little shocking: two beautiful and delicious loaves. Both loaves taste mildly sour, although taste testers agree that the revived-starter loaf is slightly tangier.

Test bake #2

On Day 5, after a total of six feedings, I try another test bake—this time including the brand-new starter; the revived starters, and my well-maintained regular starter.Sourdough Starter Troubleshooting, part 2 via @kingarthurflourAgain, the results are surprising: three nice loaves, each with a similar rise and crumb structure. The only real difference is in the flavor of the breads. Each has mildly sour flavor, but the brand-new starter yields a slightly blander loaf.

Sourdough starter troubleshooting: the takeaway

It’s definitely worth trying to revive a neglected starter (so long as it shows no signs of contamination). Pour off any discolored hooch, and start feeding it twice a day at room temperature. If it rises well and has a good aroma after three to four days, you’re back in business!

We’d love to hear your own sourdough starter stories and questions below. Did you revive your starter from the brink of death? How long did it take? Is it thriving now?

Barbara Alpern

Long time professional artisan bread baker, caramel maker and member of our Baker Specialist team, Barb grew up in Ann Arbor, Michigan and has four grown sons. She has baked in Michigan, Maine, Vermont, and Texas (if you count baking cookies for her son's wedding!).


  1. Tracy

    Hi! I’m brand new to bread baking. My good friend came over this past weekend to teach me out to make sourdough and gave me a spoonful of her starter she got from a KAF class four years ago. We mixed it in a jar with equal parts flour and water, and put in fridge. A couple days later and no bubbles or growth in size. Did I do something wrong?

    1. The Baker's Hotline

      Hi Tracy, you’ll want to keep the starter at room temperature after you feed it, especially if you’re starting with a small quantity of starter like 1 tablespoon. You can try taking it out of the fridge, dividing it in half and adding fresh water and flour. Let it rest at room temperature for 24 hours and then repeat. Keep feeding it, leaving it at room temperature between feedings, until you see bubbles and visible expansion. Once it has established a regular pattern of growth, you can put it in the fridge between feedings for up to about one week at a time. Good luck and happy baking! Kye@KAF

  2. Alex

    Dear All,

    I have baked sourdough bread in multiple countries and have grown starters for years, but I am faced with a question that I am struggling to solve.

    I keep getting a thin skin that wrinkles when you spoon it on top of my starters. I have three different ones: Pineapple, Passionfruit and Plain.

    They all bubble, smell healthy, no discolored streaks in them that confirms that they are off.

    The containers and equipment are clean, I use filtered water or fresh juice. Even newly established starters develop that and what is also unique is that the hooch doesn’t form.

    I currently living in the Caribbean. But find this new development weird.

    Would post pictures, but don’t know how.
    Thank you in advance!


    1. Barbara Alpern, post author

      Hi Alex, most often when a starter develops a skin or crust on top, this is a sign that it needs to be covered more carefully. When we recommend covering a starter “loosely,” this is not because the starter requires oxygen in order to ferment, but because fermentation gases can build up in a closed container and pop the lid off. It’s fine to cover the container securely with plastic wrap (which will stretch rather than pop off) to protect your starter from drying out. A towel or cheesecloth allows too much air flow, and can contribute to the surface of the starter drying out. If you don’t think dryness is the problem, I’m wondering if the juices you use may be contributing to the developing film? I’ve only ever used juice in a starter during the first few days of the creation phase, so I’m not sure how the added sugar that juice provides will affect the biochemistry of the starter over time, or if this could cause a film to form. If you’d like to attach a photo you can email us at customercare[at]kingarthurflour[dot]com.

  3. Erik Geele

    I’ve just begun baking bread with a wild sourdough starter and my loaves are going slack. I like the texture of the bread and the mild sour taste but my loaves are noticeably spread out and the bottoms acquire no color. My starter had an alcohol smell so I began feeding more often. Still same results.

    1. Barbara Alpern, post author

      Hi Erik, the first step in achieving sourdough bread that rises well is to be sure that your starter is very healthy and active. Try feeding your starter twice daily at room temperature for a day or two before you plan to bake in order to insure that your starter is performing well. Time your baking so that you add your starter to the recipe when it’s at its highest point of rising after having been fed at room temperature. Once you’ve mixed your dough it’s important that the dough is given adequate time to ferment, but over-fermentation can lead to a slacker dough and less coloring during baking. It may be helpful to try baking your bread a little earlier and see if this improves the rise and loaf color. Other possible factors that could be contributing to the results you describe are an excessively wet dough, inadequate dough development, loose shaping, or baking on a stone that hasn’t been fully preheated. As in all things baking, there are multiple factors that contribute to either good or bad results, so it’s sometimes hard to pinpoint one thing that should be changed in order to resolve an issue. For beginning and advanced sourdough bakers alike, I recommend finding a good recipe and following it as closely as you can. Our Naturally Leavened Sourdough Bread recipe is a great place to start.

  4. Lou Ann

    I’ve been making sourdough since January with a started I made at that time. It’s been going well except for this last batch. The dough seemed higher in hydration and although it had a good rise, it didn’t have a good oven rise and there were huge holes in the crumb. I’m thinking there wasn’t enough flour or a problem with the rise to hold the structure. Any recommendations so this doesn’t happen again? Great taste just no pretty to look at.
    Lou Ann

    1. The Baker's Hotline

      The best thing you can do to ensure fantastic loaves of sourdough bread is to feed your starter regularly at room temperature about two times a day for two or three days before baking. This consistent feeding process can often help reset your starter and also make it more active. As a result, loaves of bread made using the starter tend to have a better structure, rise, and flavor. Another approach that may help is using bread flour to make your final dough. (Feed your starter with all-purpose flour for regular upkeep and maintenance.) Bread flour has a slightly higher protein level, which will give your dough more support and oven spring, and it’s also a bit more absorbent, which will help you achieve the right dough consistency in the humid summer months. We hope this helps, and happy baking! Kye@KAF

  5. Maureen

    I am a rank beginner and I didn’t realize I had to revive my solidified starter that I was given. I used it straight from the fridge…adding it to the flour and water to make the sponge.. nothing is happening to my 4 quarts of flour/water mixture with the old starter after 24 hours. . Do I throw it out or can I add some yeast and flour and bake it?

    I have a about 1/2 cup of the old starter still in the fridge so I will add I/2 cup water and 1/2 cup flour and keep it at room temperature and feed it every day! Is that how to proceed for my next trial?

    1. Barbara Alpern, post author

      Hi Maureen, I’m guessing the sponge will require some added yeast, flour and salt to be useable, although make sure the mixture still smells good and isn’t showing any signs of mold or bacterial growth before adding ingredients. Feeding the starter you have remaining in the refrigerator sounds like the best idea. Try feeding the 1/2 cup (4 ounces) of starter with 1/2 cup (4 ounces) of water and 1 scant cup (4 ounces) flour at room temperature twice daily (about 12 hours apart). Be sure to discard all but 1/2 cup starter each time you feed it. Within a few days I expect your starter will have a nice, mildly tangy aroma and will be doubling in size after 6-8 hours. Once your starter is showing this kind of predictable behavior, then you can start baking!

  6. Adam

    With my sourdough starter, in the beginning for my first feeding I did not change over from whole wheat flour to unbleached as I didn’t realize. The second feeding I switched over to unbleached flour and follow the instructions. Now entering day five I realized I’m using King Arthur unbleached bread flour. The smell isn’t great, what should I do? I fed with one cup Pillsberry unbleached and a half a coup of water. Please HELP!

    1. Barbara Alpern, post author

      Hi Adam, none of the flours you’ve used will cause damage to your starter, so rest assured you’re still on the right track. Day 4-6 can often result in a slump period, where the starter is creating bubbles, but doesn’t rise much. This can cause some bakers to despair and throw in the towel, when a little more patience and persistence would pay off. I would recommend giving your starter another whole wheat feeding next time it’s due to be fed, and then switch over to our unbleached all-purpose flour for your remaining feedings. Keep feeding through day 10 and I expect you’ll see your starter begin to rise and fall more predictably, and develop a slightly tangy aroma. Once you observe this kind of behavior–you’re ready to start baking!

  7. Ellen

    I hadn’t fed my sourdough for over a year — and it was an old pioneer sourdough that I had gotten from my father. So I asked him for some more starter. We both forgot and I went home without it.

    About a week later, my father called to tell me that my stepmother had (by mistake) put all the starter into the latest batch of bread and had baked it. He was wondering if I could give him some starter! I told him that I only had the sad starter that had been neglected for over a year. I didn’t think it would revive, but decided to give it a try (I’m a microbiologist and am used to treating microbes gently).

    At first I only took a couple of spoonfuls of the starter and placed it in a bowl in the oven with the light on. After two days, nothing had happened. Then I decided to go ahead and go for it — All or nothing!! Well, it rose and it has been acting better than ever. What is funny is that after all that work, my father was able to get some starter from a friend of his to whom he gave the starter a few years earlier.

    By the way, I know about what those experts say about strains of sourdough not being unique, but as a microbial ecologist, I would say that there is only one scientific study out there that actually tests that hypothesis (a scientific guess). The authors (italian) did conclude that local flour provided most of the microbes in the sourdough, but most isn’t all and potentially some of the strains of yeast and bacteria (yes, there are bacteria in sourdough) may be “core” microorganisms that have replicated and held on in those older sourdough strains. And possibly they do contribute to the taste of the finished product. While I would love to see more work done on this subject, I suspect the funding isn’t behind it. However, until more studies are done, the “experts”, not being microbial ecologists, are probably just guessing and their guesses aren’t any better than those that you or I would make.

    1. Ellen

      I stated that the strains weren’t unique, but actually meant not retaining the unique strains of the microbes that had originally been in the sourdough. And I meant that I think that while all the starters do change with environmental changes, that despite this, some of the original types (species and strains) of microbes do hang in there, contributing to taste.

    2. Barbara Alpern, post author

      Thanks, again, Ellen! We hope you’ll continue to join our sourdough conversations and offer your expertise.

    3. Barbara Alpern, post author

      Ellen, thanks so much for contributing your scientific knowledge and sourdough experience to this post! I know many sourdough bakers who wish they had your background in microbiology to help guide them in their sourdough adventures! We greatly appreciate your willingness to share your observations with all of us.

  8. Vicki Vaughn

    Help! My sourdough seems to have lost its tangy flavor. I keep it in the fridge, and feed it every 7 to 10 days. Sometimes longer if I am out of town, or busy and forget. I mix the hooch back into the starter. What can I do? Should I start over with a fresh batch?

    1. Barbara Alpern, post author

      Hi Vicki, there’s no need to start over, but it does sound like your starter would benefit from a few days of twice a day feedings at room temperature. I would recommend feeding it this way until you notice that you’re starter is doubling in size after 6-8 hours and has a mildly tangy aroma. Once you’re starter is very active and healthy, you can concentrate on flavor development during the dough phase. Try substituting a small portion of rye flour or whole wheat flour for some of the white flour in your sourdough recipe. Whole grain flours, particularly whole rye flour, can contribute to developing more sour flavor in your bread. Another method for enhancing the tanginess of your sourdough bread is to refrigerate the dough during part of the fermentation process. Some of our sourdough bread recipes that utilize one or both of these techniques are our Extra Tangy Sourdough, Artisan Sourdough Bread, Pain au Levain, and our Naturally Leavened Sourdough Bread.

  9. Sheri Sidwell

    Hi Barb!

    I must tell you, last week you saved two grateful starters’ lives (and me from a minor heart attack). Let me explain — two weeks ago, the husband and I were going out of town for several days, maybe a week, so good starter mom that I am, I fetched the kids out of the fridge for an early weekly feeding, made up some crackers for the drive, put a pizza dough in the freezer, set my replenished jars on top the fridge to oomph up a bit, went back to packing, . . . and LEFT. Yep. Really didn’t give it a thought until I was back home eight days later, unpacking the cooler, and then (I’m told) let go a string of expletives that had the husband running into the house, thinking we’d been robbed. I had actually been thinking, “Well, as soon as I get all this put away, I’ll feed my starters. . .where ARE my starters??” and for the tiniest second I could just see those horrid sourdough thieves. That is, until I looked up. I almost cried, they looked so bad. I got them down for inspection and there was a good half or three-quarter inch of darkish fluid on top of them both, with the whole wheat the worst. Little AP looked purty bad, too, but she didn’t smell nearly as strong as WW. And nary a tiny bubble between the two. I really did have the jars in my hands, ready to dump, when it occurred to me that I’d scanned this blog a while back, and before I did anything drastic, best to take a breath and fire up the laptop. I’m so glad I did. For whatever reason, I was thinking of refrigerated starters being forgotten and then revived — not just plain forgotten (and forgotten again, in broad DAYLIGHT, no less, and at much warmer than room temperature. Remember, I’d been baking that day). Thank you so much, Barb. I knew I’d seen those pics of the starters with the black fluid; I just had to find you again. My husband actually heard my sigh of relief; he stuck his head in the door and asked, “Yay or Nay?” When I said yay, the man just smiled and asked me for carrot cake. I threw a pen at his head. Happy ending. It took a few (4) days, and more than a little flour, but the two- year-olds are thriving again. Today was feeding day, so I made Clay’s Multigrain with the WW, and it turned out great. Tomorrow, with the AP, I’m baking a carrot cake to take to Mom’s for Easter (don’t tell the hubs; he thinks it’s all for him since, of course, I made him wait almost a week).

    Again, Thank You So Much,
    And Happy Easter!

    Sheri Sidwell

    P.S. (and no matter what he says I did NOT say the *F* word five times. Once, maybe).

    1. Barbara Alpern, post author

      Hi Sheri, what a great story! You had us all laughing and cheering here at King Arthur Flour. We’re so glad that this post came at just the right time to throw a helpful lifeline to your two-year-olds. It made our day to hear that we were able to provide support and encouragement for your sourdough adventures (and misadventures)! Congratulations on reviving your starters and capturing the highs and lows of sourdough baking in such a wonderful way! And I hope your husband appreciates the sourdough carrot cake, and the effort it took to create it! Happy Easter to you and yours!

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