Home BlogFermentation Science Sourdough Starter Mold: Common Sourdough Starter Problems and How to Fix Them

Sourdough Starter Mold: Common Sourdough Starter Problems and How to Fix Them

by Kaitlynn Fenley
a mason jat half full with sourdough starter.

Learn how to fix common sourdough starter problems like sourdough starter mold, weird smells, strange colors and lack of bubbles.

What Microbes are in Sourdough Starters?

Many types of microbial fermentation happen simultaneously in healthy starters. It is a mixed type of fermentation because starters consist of a rich, wild, mixed culture of yeast and bacteria.

When you culture a sourdough starter, wild yeasts metabolize wheat sugars and carbohydrates into alcohol. At the same time, bacteria consume the sugars, alcohol, and starches in the starter to produce acids.

The bacteria can metabolize carbohydrates from the flour into acids. They can also convert the yeast-produced alcohol into acetaldehyde and acetic acid. The rise and bubbles come from the wild yeast, and the rich sour flavor comes from the bacteria.

How to Make a Sourdough Starter

It’s simple to make a sourdough starter at home; you only need flour and water!

I prefer to feed my sourdough starter sprouted rye flour, but organic bread flour works well too.

Getting a sourdough starter established is even easier if you can begin with a starter from someone else. I am selling my sprouted rye sourdough starter, Reuben, here.

Preventing Sourdough Starter Mold

It’s easy to keep your sourdough starter from molding. Just follow these three rules:

  1. Discard and feed your starter fresh flour and water every 24 hours. Do not skip any feedings. If you need to skip a feeding, put your starter in the fridge.
  2. Feed your starter in a clean jar. Move your starter to a fresh, appropriately sized, clean jar every other day.
  3. Use the right flour to water ratio. For bread flour starters use 1:1, for most whole wheat and rye flours use 1:2.

Sourdough Starter Mold

The best way to keep your sourdough starter from molding is to feed it often enough. You must discard sourdough starters and feed them fresh water and flour every 24 hours minimum.

It’s always a good idea to move your starter to a fresh, appropriately sized, clean jar at least every third day. I move my starter to a clean jar daily.

Usually, mold destroys any ferment. However, sourdough starters are the most forgiving of any fermented food. White mold or fungus can grow as a pellicle on the surface of your starter for three main reasons.

First, mold can grow when you do not discard and feed your starter often enough. Second, you may encounter mold problems if you don’t switch to a clean jar often enough. Third, if there is a lot of air space in the jar, the top of the starter can dry out and cause a pellicle to grow.

If you experience what looks like mold on your starter, just carefully remove the pellicle and all the fungal growth you can. There should be a bit of unscathed sourdough starter underneath.

Then, using a clean utensil, grab a small amount of untainted starter that was not near the mold and add it to a new jar. Then discard and feed as usual.

If there is black, blue, or green growth that is fuzzy, you should throw it away and start over. Next time, make sure you feed your starter within 24 hours. If you cannot feed your starter within 24 hours, place it in the fridge for hibernation.

What if My Sourdough Starter Smells Like Alcohol?

Are you asking yourself “why does my sourdough starter smell so bad?” The answer depends on the type of smell.

Don’t freak out if you smell strange smells like alcohol or acetone. These sourdough starter smells are quite normal and interesting!

This smell means that the bacteria in your starter need more oxygen to finish converting yeast-produced alcohol into acetic acid. If there isn’t enough oxygen, the bacteria get stuck in the middle of the conversion process, with a build of acetaldehyde (which smells like nail polish).

Once you expose them to more oxygen by stirring, discarding, and feeding, they can finish converting acetaldehyde into acetic acid.

It’s simply the smell of bacteria converting alcohol to acids for flavor! You can also put your starter near a fan, maybe a houseplant, or an open window on a cool day for more air circulation.

What Should a Sourdough Starter Smell Like?

A healthy sourdough starter should smell sour like vinegar and yeasty like beer. The smell should be pleasant but brightly sour.

Any off or repulsive smells are usually because of poor feeding practices, or from feeding with poor quality flour. Make sure you are using high-quality organic flour to feed your sourdough starter.

My Sourdough Starter has Liquid on Top

If you see liquid on the top of your sourdough starter, do not be alarmed. This is normal and no big deal.

If you find a liquid layer on the top, it could be alcohol produced by yeast, or it could mean your starter is simply too watery.

This is a common problem when using white flour, like bread flour or all-purpose to grow and feed a starter. When using rye or whole wheat flour more water is absorbed when compared to using bread flour or all-purpose.

The germ and bran that are present in whole wheat flour can absorb more liquid; white flours lack the germ and bran and only contain the endosperm which does not absorb as much water.

If your starter has watery separation, pour the liquid off, discard 3/4 of the starter, then feed it with equal parts water and flour. It’s best to discard and feed your starter with a 1:1:1 starter-to-flour-to-water ratio.

Try using thicker flour like whole wheat or rye.

an above shot of a sourdough starter in a mason jar

Pink Discoloration and Sourdough Starter Mold

If you are not using rye flour, and you notice a more prominent pink discoloration in your starter or on the surface of your starter, you need to throw it out and start over.

The discoloration is most likely from Serratia marcescens, an undesirable bacteria often found in pipes and tap water. Sometimes pink color can be from mold.

If you use 100% rye flour to feed your starter, sometimes your starter can take on a soft reddish tone.

Purple Discolored liquid

Purple-hued liquid on the sourdough starter is called “Hooch,” which is alcohol. It accumulates on the surface of your starter when you do not feed it enough.

Hooch is most commonly clear, beige, brown, purple, gray, and black. The color depends on the flour and the unique microbes present.

Hooch is just the alcohol given off as wild yeasts ferment wheat. Don’t worry if you have a discolored liquid layer in your starter jar.

It is not a sign that your starter is dying. However, it does indicate that your starter is hungry and needs to be fed. Just pour off all the liquid, discard 3/4 of the starter, then feed.

Refrigerating and Reviving Your Sourdough Starter

If you’ve used some of your sourdough starter to bake, and you do not plan on using your starter again anytime soon, you can hibernate it. 

  1. In a clean jar add:
    • 50 grams starter mixture ( 4 Tablespoons )
    • 75 grams of flour (if using whole wheat or rye, use less flour here)
    • 75 milliliters filtered water
  2. Stir until evenly combined, and scrape down the sides of the jar.
  3. Let it sit at room temp until bubbly, then close with a solid lid and place in your refrigerator. 
  4. Feed starter every 2 weeks. (note that starters can be neglected in the fridge and still be revived. It’s okay if you leave it longer than two weeks without feeding.)
  5. Reviving sourdough starter from fridge: move to room temperature and continue to discard and feed every 24 hours.

Why is My Sourdough Starter Not Bubbling?

Of all the sourdough starter problems, this is the most common. You may be wondering if your sourdough starter is dead simply because it is not bubbling.

If you feel like your sourdough starter is not bubbly and rising enough, here’s what you can do:


Starters can be quite soft and wet. If you are at work all day or sleeping, you may miss it expand and rise. This is normal since it is so hydrated.

If you want your starter to “hold” the rise a little longer, make the starter thicker by using a bit more flour and less water. CLICK HERE for our sourdough starter recipe.

REMEMBER: The amount of flour and water you feed your starter can vary a bit. The thing to remember is that different flours absorb different amounts of water. For rye and whole wheat starters, you need about a 1:2 ratio of flour to water for feedings (so that would be 50 grams flour 100 grams water). For white bread flour and all-purpose flour, you need a 1:1 ratio of flour to water (so 50 grams flour 50 grams water) for feedings. If you notice early watery separation, just add an extra spoonful of flour.

Try more complex flours

Try feeding your starter a mix of heirloom flours from somewhere like Lindley Mills. I like a mix of rye, spelt, and buckwheat when I feel like my starter needs a boost.

You can also try feeding your starter sprouted flours, like sprouted Enkinhorn, sprouted spelt, or sprouted rye. These types of flours absorb more water, so will give you a thicker starter that can hold a rise longer.

Add in some fermented vegetable brine

Wild Sourdough yeasts benefit from the presence of bacteria and vice versa. So adding a little bit of sauerkraut brine in at the beginning just speeds up the formation of this awesome microbial relationship.

I use fermented vegetable brine to make starters all the time. My starter, Reuben, was originally started with fermented vegetable brine that is now 2.5 years old. I find the flavor to be more developed and rich with my brine starters, and I prefer it. My loaves come out beautiful, too.

How Long do Sourdough Starters Take to Rise?

I feel like timelapse videos of starters rising have confused people on sourdough starter timelines. Your starter will not rise on your watch, it really depends on feed frequency and temperature.

After feeding, a sourdough starter can take anywhere from 5-24 hours to bubble up and rise. Be patient with it; you may need to wait for the bubbly rise, or it might happen while you’re sleeping.

lso, your sourdough starter may not look like the pictures here, if it’s bubbling and has expanded, you can use it to bake.

Most of the wild yeasts in sourdough starters originate from the flour used to make the starter. Those yeasts originated in the soil in which the wheat was grown. Therefore, You’ll get the most species-rich starter by using a mix of organic flours plus a little wild fermented sauerkraut brine.

Did I Kill My Sourdough Starter?

It’s quite hard to kill a sourdough starter. Even the most neglected starters can often be brought back to optimal activity. I think it’s important that we go over a few things that have no effect on your starter and definitely will not kill it:

  1. Metal spoons: This is a ridiculous claim. While you shouldn’t store it in a metal container for long periods of time, you can totally stir it with a metal spoon. Stirring with a metal utensil does not change anything about your starter.
  2. Inaccurate flour measurements when feeding: The amount of flour and water you feed your starter can vary a bit. The thing to remember is that different flours absorb different amounts of water. For rye and whole wheat starters, you need about a 1:2 ratio of flour to water for feedings (so that would be 50 grams flour 100 grams water). For white bread flour and all-purpose flour, you need about a 1:1 ratio of flour to water (so 50 grams flour 50 grams water) for feedings.
  3. Refrigeration: Yes, you can store your starter in the fridge. As long as you still discard and feed every 1-2 weeks, it’ll be easy to start back up. This is a great way to reduce discard and flour consumption if you’re taking a break from baking. Honestly, I’ve neglected a starter in the fridge without feeding for 2 months, and it still came back to life with the first feeding.

Generally, sourdough starters will only die from severe neglect. Keep it between 70-80 degrees, keep it out of direct sunlight, discard and feed every 24 hours, take care of any issues that arise in a timely manner and you won’t kill it.

Reviving Dehydrated Sourdough Starter

Still can’t get your starter to cooperate? I suggest buying some dehydrated starter from a quality baker and starting with that. Check Etsy for dehydrated sourdough starter options.

Sourdough recipes to try with your starter

More Sourdough Recipes

author avatar
Kaitlynn Fenley Author, Educator, Food Microbiologist
Kaitlynn is a food microbiologist and fermentation expert teaching people how to ferment foods and drinks at home.

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Leave a Comment


Marianne June 23, 2020 - 11:55 pm

I used some of my active SD starter this morning to make a bread dough, and I fed it (after removing what was needed) with 1 cup water and 1 cup flour (didn’t weigh it). Realizing it might overflow container, I removed some of it to a second container. Nothing is happening after 8 hours in either container. Did I over feed it, since I had fed it yesterday too, for my bread today.

Kaitlynn Fenley June 24, 2020 - 3:59 pm

That’s a lot of flour and water. So, it’s likely that it just needs some time for the yeast to multiply and establish. Once they populate the mixture a little more you should see bubbles. If you want the starter to visibly rise, decrease the water amount next time for a thicker starter.

Den December 21, 2020 - 12:07 am

Hi! I have a question! One day my starter raised beautifully but when I came back at the end of the day to feed it, it had developed a thick skin and some gray hair/fur covering over the surface. I’ve already tossed it in the fear of mold. But do you maybe have any idea of what could have caused it? I’m using organic whole wheat flour and the starter was about a week old. I have some photos if it helps… It was just doing so well, I’m shocked mold grew!

Kaitlynn Fenley December 21, 2020 - 8:49 am

Hi! You should read the section in this blog post under the heading “mold”.

Michelle M February 21, 2021 - 8:29 pm

Thanks for the article. Easy trouble shooting from such clear instructions.
I am adding 1 cup each of flour and water to my new) starter each day. It was very thick so I added a 1/8th of a cup extra water each day. It now has a watery layer on top. I see in the trouble shoot above that I should drain this liquid off with 3/4 of the starter and resume with less water.
My question is, can I use the liquid mixture that I drain off for bread making? It seems wasteful to tip it off and discard.
I have been using home ground wheat. I am not sure which type of wheat.
Thank you

Kaitlynn Fenley February 22, 2021 - 12:29 pm

I wouldn’t suggest using the liquid layer on top for anything. It likely does not taste very good. It may have an alcohol/astringent flavor.

Gail March 13, 2022 - 1:43 am

I accidentally added a half a teaspoon of Himalayan salt to my starter I was mixing a recipe put the salt in the wrong bowl. Very upset now, is it dead? Do I start over 🙁

Kaitlynn Fenley March 13, 2022 - 7:26 am

It’s not dead! you can fix it!. Feed your starter with excess water: I’d feed it 50 grams of bread flour and 100 grams of water in a large jar. You’ll notice the water will separate to the top after 24 hours. Pour that off, then feed like normal. It’ll be fine.

Tiana December 31, 2020 - 12:31 am

Hi! Thanks for this post. So I’m on day 11 of my sour dough starter. It’s not doubling in size! I think because I’m in Canada it’s too cold? I tried everything to help fix it. I’m using filtered water, 1:1 ratio, a homemade proofing basket,…Today I tried all rye flour (previously used whole wheat bread flour) but after 5 hours it’s still not rising at all. Not sure what to do now and I just want to cry and give up 🙁

Kaitlynn Fenley December 31, 2020 - 7:54 am

What sourdough starter recipe did you use?
Starters can take much longer than 5 hours to bubble up after feeding. When it’s cold here, I have to feed my starter and wait 12 to 24 hours for it to bubble up before using it in bread recipes. Since I feed my starter every single morning, it’s always bubbly and ready for use in bread recipes the next morning.

Don’t give up!

friendlyread1 January 18, 2021 - 9:13 am

The starter recipe I have tells me to feed my starter with flour, milk, and a couple of pinches of sugar each time I use it. My starter is sweet now. Is there any way to fix it? Is there something I can feed the yeast with without using sugar? Thank you!

Kaitlynn Fenley January 18, 2021 - 9:46 am

oh… interesting. I would never feed a sourdough starter milk or sugar. You can create and feed a sourdough starter with just flour and water.

Teri Lyons August 9, 2021 - 10:55 pm

My sourdough starter doubles in size when I feed it and has lots of bubbles but it does not float. It’s a little colder here in winter (Australia Brisbane) would this affect the floating ?

Kaitlynn Fenley August 11, 2021 - 2:52 pm

The temperature should not influence if it floats or not. What kind of flour are you using, and how hydrated is your starter? If your starter is very dense, it will rise and bubble, but not float. You can still use it to bake if there’s visible rise and activity.

AlwaysLearning December 23, 2021 - 3:13 pm

That is the recipe for Amish Friendship bread, @FRIENDLYREAD1. As Kaitlyn says, sourdough starter is made with just flour and water.

Max Smith January 20, 2021 - 8:32 am

My (1st) starter is the product of yeast water that took 13 days to bubble, but then smelled of alcohol, as it should. After using it to make 100% saturation starter, I have created gum. Virtually insoluble gum. Do I start over?

Kaitlynn Fenley January 20, 2021 - 8:53 am

I don’t know what recipe, flour, or feeding methods you used to create your starter/”gum”, which makes troubleshooting difficult. so I’m going to say start over. Also, it shouldn’t smell like alcohol, it should smell pleasantly sour.

Jacob January 24, 2021 - 9:09 am

My starter looks like glue and smells like vinegar, can I bake with it? I use 50/50 flour to water ratio, started with wholewheat flour then fed with unbleached white flour. At first it smelled sweet and boozy, then it turned acetic as the weather got colder. It bubbles on the top but doesn’t have a sticky bubbly appearance like in the pictures, it doesn’t rise but is fermenting I think (produces a lot of gas). Should I start feeding it with wholemeal flour?

Kaitlynn Fenley January 24, 2021 - 9:39 am

Sourdough starters should smell kind of like acetic acid (vinegar). That’s where the “sour” in sourdough comes from. I explain the microbial process of converting alcohol into acetic acid in this blog post, under the heading “acetone or nail polish smell”.

In the pictures here I do not use a 1:1 hydration. So, of course, yours looks different. I explain why your starter looks different under the heading “My Sourdough Starter isn’t Rising!”

If it’s bubbling and smells pleasantly sour, I think you can use it to bake!
Let me know if you have any more questions.

Kristin J March 10, 2021 - 3:59 pm


My starter has been in my fridge, untouched, for 7 months. I know, i know.

I took it out today and fed it. It my surprise, it’s bubbly, but has only risen about a half an inch. Should i continue to discard and feed to get it back to normal?

Kaitlynn Fenley March 12, 2021 - 2:26 pm

Yes! starters are really forgiving like that. I’d say discard and feed every day for a week, and then it should be back and ready for baking.

David January 1, 2022 - 11:50 pm

I had a starter hang out ignored in the back of the fridge for 3 years (no kidding) and went to ressurect it this week. I poured off the hooch, and fed it twice a day 50g starter to 100g flour and H2O and kept it in a warm place. For a few days it didn’t do anything at all but it’s now come back strong, esp after I started mixing in 30% whole wheat flour with the white.

There’s no sign of mold or other weirdness, so I’m hoping it’s good to go. Amazing what those yeasts can put up with and survive!

Kaitlynn Fenley January 2, 2022 - 8:26 am

That’s wonderful! so glad it bounced back!

When people worry if their starters stored in the fridge for a while are dead… I think about how researchers cultured 5,000 year old starter from egyptian pottery found at an acheological dig site, and brought it back to life, then baked bread with it. They can survive quite a lot lol

Ryiaala March 18, 2021 - 4:39 pm

I was feeding my starter a mix of 1/4 organic rye and 3/4 organic AP flour and it was fabulous. Then I switched to 1/2 organic whole wheat and 1/2 AP and literally nothing happened. I fed it twice with this mix and still nothing. I switched back to my original mix and the starter is doing great. Do you think the problem would be “dead” wheat flour? What could cause this? Thank you!

Kaitlynn Fenley March 22, 2021 - 10:39 am

Interesting! I’d have to test the brand of whole wheat flour to know for sure what is going on. The microorganisms may just take longer to metabolize the whole wheat flour. Sometimes when you switch to a more dense flour, like whole wheat, it can take 24 hours or so for your starter to show activity.

Laura Llano Moraga March 23, 2021 - 4:09 am

My sourdough gets like a layer of light purple dough.. I don’t know if I should start over or take out the purple dought from top and feed it again. I already did it once and the purple came back. I used buckwheat flour and water.

Kaitlynn Fenley March 23, 2021 - 10:10 am

It’s probably because you used buckwheat flour. This type of flour can sometimes cause purple-ish hues. Try using a fresh, clean jar and a different type of flour.

lindsey haas March 25, 2021 - 11:02 am

Wondering if you had any thoughts on this situation. I gave my sister-in-law some of my sourdough starter and she said it went bad really fast and it didn’t bubble. I keep mine in the fridge and feed it once a week. And this time it had a lot of hooch like three times as much as normal. I’ve had this sourdough starter for over a year. Do you know why it would be doing this?

Kaitlynn Fenley March 27, 2021 - 12:48 pm

I’d love to help, but I’d have to know more specifics on what she means by “it went bad” to help any further with that.

As for yours, sourdough starter microbial communities can change over time especially at cold temperatures. I’d suggest feeding it every day at room temperature for a week, then you can resume the fridge storage/feeds. This helps balance out the ratio of yeast to bacteria in the starter, which should fix your hooch problem.

James April 2, 2021 - 8:40 am

Do you know about brown rice sourdough starter? Mine has turned a bit reddish. It doesn’t smell bad. Not sure if I should throw it out and start over.

Kaitlynn Fenley April 2, 2021 - 10:26 am

It’s hard to tell you since I cannot see it or smell it. If it’s a dull very light reddish color, it’s probably just from the color of the brown rice changing through fermentation. If it seems more like a bright red or pink, it could be from a contaminant like Serratia.

Make another brown rice starter in a separate, very clean, sterilized jar. Use boiled water that has cooled, and see if the same color develops. If it does, that’s just the natural color. If it doesn’t, then it turned reddish from cross-contamination bacteria.

Ross May 6, 2021 - 7:43 pm

Hi Kaitlynn,
My rye sourdough starter (made from equal weights of flour and water) looks good and very active after 4 or 5 days of feeding. When I take off the top of the jar it initially has a not unpleasant fruity aroma, however when I break the surface and mix it up it produces a putrid, metallic smell that is not at all pleasant and smells definitely wrong! I have had the same result with my last few batches of starter and as far as I can work out I’m doing everything right. The only thing I can think of is that I’m not controlling the temperature properly by not keeping it at a constant warm around 25C (77F)?
Have you got any ideas why my starter is smelling like this? Many thanks, Ross D

Kaitlynn Fenley May 8, 2021 - 7:16 am

What kind of top are you using on the jar? and what recipe are you using? I do not suggest equal weights flour and water. We have a recipe for rye starter I suggest following.

Amanda June 28, 2021 - 11:07 pm

Thanks for this article, I’m just trying to figure out what went wrong so it doesn’t happen again. I’m guessing just that my jar or spoon wasn’t clean enough? I made my starter 7-8 months ago, I’ve had times of being really consistent with it and times of not so much. But it’s been warmer in the house now and it seemed like it was deflating sooner, so I feed it sometimes in the morning along with the night feeding, this morning I did not feed it and tonight (~24 since last feeding) and it had a slight fuzz over the surface same color to maybe a slight gray color. had a slight nail polish remover smell but not more than when it’s been a little hungry before. I followed the instructions under the “mold” section. I just trying to figure out the best way for it to not happen again! It has been dry on the top lately when I feed it but otherwise has been working wonderfully for me, even just this morning it looked like it was double-triple it’s size. (Whole red wheat flour, 100%hydration, measuring by grams)
Oh I don’t know if this would have anything to do but I had it a bit closer to my kombucha and had started 3 gallons vs one as of last week. That’s the only other thing that has changed.

Kaitlynn Fenley July 2, 2021 - 12:23 pm

Hey there,

It shouldn’t have anything to do with the kombucha. What kind of lid are you using? The nail polish smell is an indication that it is not getting enough oxygen.

If your starter is more on the dry side, a dry crust with a pellicle can form on the surface. To me, it sounds like that’s what you are describing.

Amanda July 2, 2021 - 1:46 pm

I keep it in a wide mouth mason jar with a coffee filter and just the ring holding it in place, gnats are pretty bd in our house right now so I’d be afraid to use a cheese cloth, would you recommend a fabric cover of some kind or something else to cover it?

Kaitlynn Fenley July 5, 2021 - 11:22 am

A coffee filter should work fine, but I’ve never used one as a cover. I personally like to use old t-shirt pieces as covers.

Danielle July 2, 2021 - 11:51 am

Hi! So I have a recipe for a basic buckwheat sourdough bread from a health food book I’ve made and enjoyed a couple times. This time I let it sit for 24 hours instead of twelve and the sour smell changed to more of a garbage smell…I didn’t notice discoloration and it rose more than usual. Do you think it is safe? I’m baking it now 😅

Kaitlynn Fenley July 2, 2021 - 12:20 pm

Hi there! Buckwheat flour does not ferment the same as wheat flour. I cannot tell you if a recipe that I have not seen, that was written by someone else, is safe or not. A “garbage” smell sounds quite unappetizing, so eat at your own risk.

Linda July 4, 2021 - 1:49 pm

I dried my sour dough starter. What is the best way to bring it back?

Kaitlynn Fenley July 5, 2021 - 11:24 am

Just add the dried starter to some fresh water and flour and feed every 24 hours as normal. You can use our sourdough starter recipe for feeding instructions.

Madeleine November 11, 2021 - 11:50 am

Hi! I was given some sourdough starter from a friend and it has some ooey, clear mucus like bits floating in the starter. Is this normal? I’ve never seen it before. It’s wheat flour based, was kept in the fridge with cheesecloth over top. The bits remind me of scoby. I’ve just fed it for the first time today and hope it will rise.

Kaitlynn Fenley November 16, 2021 - 2:09 pm

I think someone else commented here about something similar. It’s possible that this is normal since sourdough starters do have the same types of acetic acid bacteria that build kombucha scobys… however, I’ve never seen it happen before. I’d say just keep discarding and feeding and see what happens.

Leslie October 26, 2022 - 3:53 pm

Thanks Kaitlynn! Very helpful post. I’m trying to make a spelt flour sourdough starter (can’t digest wheat or rye) and have had several flops in which it would develop fast on day 2 and then nothing further (kept trying for about a week of daily feeds before starting over). This time I’ve used a half tsp of organic honey with each feed (read elsewhere the sugar can help it develop) and it does seem to bubble up, but only within a small, 1 inch top layer; the 3-4 inches of starter underneath has zero bubbles in it. Same thing every day. Of course i stir it thoroughly and make sure there is no solid deposit of overly thick matter at the bottom. Do you have an idea how to get it to “start” throughout? This 1 inch bubbly layer on top is not enough to bake a loaf of bread

Kaitlynn Fenley October 27, 2022 - 9:31 am

You can try our gluten free sourdough starter here: How to Make a Gluten-Free Sourdough Starter From Scratch

Dana July 11, 2021 - 3:41 pm

I was given a starter more than 15yrs ago and I was beginning to think I was somewhat proficient, as my loaves were tender/tasty. The starter suddenly got weird, with recent loaves looking beautiful when I take them out of the oven, but there’s a giant pocket under the top crust; then it collapses into adding a dense rubbery loaf. I started a clean jar with a 1/2C w/w Lindsey mill bread flour and a 1/3C spring water. When I added a tablespoon of my starter, I could hardly stir it, as I now had a rubbery mass. I’m ready to start anew, but perplexed about how this happened after so many years of success. (I have some original starter in the freezer. Dare I use it?) Thx!

Kaitlynn Fenley July 16, 2021 - 7:03 am

This sounds like an issue with the water ratio in the bread recipe and an issue shaping the loaf, not an issue with the starter. Are you stretching and folding the dough enough while it rises? and doing a pre-shape plus a final shaping?

Have you worked with quality bread flour before? It has a much higher gluten content.

Dorothy Owen August 9, 2021 - 11:29 am

Hi, my starter always forms like an actual scoby on top. If I dont feed it for a week, it gets about half inch thick. It is a neutral color and not dark or smelly. I usually throw it away, but was wondering if my sourdough is a hybrid of kombucha and sourdough, like a new species. I’ve been using the same starter for 7 years. It makes fine sourdough bread. Is this common? Thanks

Kaitlynn Fenley August 11, 2021 - 2:50 pm

Wow! That sounds very interesting! I’ve never seen this before, but it is very possible.

Sourdough is a mix of wild yeast, acetic acid-producing bacteria, and lactic acid bacteria. In Kombucha, acetic acid-producing bacteria (AAB) are the main type of bacteria in SCOBYs. AAB are the microorganisms in the SCOBY community that produce cellulose to build the SCOBY structure.

If your starter has a high population of AAB, that would explain the SCOBY-like structure forming. I’m unsure if it is common, but I’m not surprised that it happened.

Catherine September 9, 2021 - 9:13 pm

Hi! I found this post looking for some troubleshooting for my starter. I’ve had mine for years, make bread all the time. But one day forgot to put it in the fridge and left it in the kitchen counter for three days. When I opened it noticed the parmesan smell and also noticed that the surface of it looked oddly velvety (as opposed to shiny that I always see). Discarded almost all, grabbed new container and reanimated with several feeds every 12 hours. Now is strong and healthy BUT still has the weird velvety surface. I’m afraid some bacteria got in it or something? Do you have any idea of what could it be?

Kaitlynn Fenley September 10, 2021 - 7:58 am

Sounds like a bloom of yeasts on the surface! This happens to mine sometimes too. The cheesy smell indicates it may be a yeast, like Geotrichum candidum, which forms velvety growth and is used to ripen certain types of soft cheeses. If you want it to go away, you can try increasing the hydration of your starter just a bit.

Catherine September 14, 2021 - 9:34 pm

I will! Thank you for taking the time to respond!!! Much appreciated.
I assume is just fine cause it springs strongly but I will try what you recommend.

Catherine September 9, 2021 - 9:14 pm

Forgot to say…thank you in advance!!! 😌

John Kennedy September 28, 2021 - 9:19 am

Thank you for all your help. I stumbled on your web page when trying to find a cure for my starter. and you saved me. My bread now has spring and that great sourdough flavor.

Kaitlynn Fenley September 30, 2021 - 9:31 am

oh wonderful!! I’m so happy that I could help save your starter!

Carol September 28, 2021 - 11:08 am

My sourdough is probably not fed as often as it should be but I always feed a day before baking. My question is why does my dough not rise? Is it because the starter is not good?

Kaitlynn Fenley September 30, 2021 - 9:33 am

Does your starter rise when you feed it? Does it bubble up before you use it in the bread recipe? Dough not rising could be due to a multitude of factors. Are you using one of our bread recipes?

Katherine England October 29, 2021 - 7:06 pm

I have a great starter but neglected it for about 6 weeks. I worry that it turned pink but don’t remember. It smelled awful when I started to revive it. I have feed it every couple of days for about 2 weeks. it looks great and bubbly but still smells weird and strong. Not like it used to. Have I killed it or has bacteria destroyed my lovely starter?

Kaitlynn Fenley November 1, 2021 - 11:25 am

Did you neglect it at room temperature or in the fridge? If you don’t have a problem with packaged yeast, you can add a teaspoon of packaged yeast to your starter to rebalance the yeast to bacteria ratio. Then keep on discarding and feeding daily like normal.

Mily November 28, 2021 - 10:00 am

I have a starter from fridge took out fed it in the morning I wanted to knead it didn’t rise

Kaitlynn Fenley November 28, 2021 - 11:51 am

It can take a while to bring a starter back to life after storing it in the fridge. Keep feeding and discarding every 24 hours and see what happens.

Marian Booth Green December 26, 2021 - 10:00 am

I am trying my second go-round making sourdough bread. I’m using bread flour. The starter is bubbly, but after I create my leaven, the next morning, there’s lots of moisture in the plastic wrap and the surface of the leaven is dry with no bubbles. What do I need to change?

Kaitlynn Fenley December 27, 2021 - 2:25 pm

how are you making the leaven? are you weighing the flour and water to measure? When using bread flour, you should use about equal parts (measuring in mass) flour and water.

Waltraud January 14, 2022 - 1:51 pm

I started a new batch of teff gf sourdough starter over the holidays and I noticed about a week ago that I have a purplish hue on top where the starter is exposed to air. The purple color is slowly expanding to discolor more of the starter. Is it going bad or just oxidation of the teff?
When I started it, I used a purple cabbage leaf and apple peel to get it going. I removed the cabbage and apple peel after 48 hrs and continued to feed every day for 10 days. Then I started refrigerating it and fed it every other day. Today marks 4 days of the starter in the fridge without feeding (the first time it’s been 4 days since the last feeding). The starter smells good but I am concerned about the color change. There is no liquid (hooch) buildup on top. Thank you for your insights in advance!

Kaitlynn Fenley January 17, 2022 - 10:15 am

If you used a purple cabbage leaf… then that’s probably why it’s purple. I’ve never worked with teff, but it also has a natural reddish purple hue.

Jerry Uhte February 1, 2022 - 2:18 pm

Hello, i like your info and replys to people with starter problems , i am a beginner too and would like to make rye bread from sourdough ! I liked a video from a German lady so i am doing what was recommenced .
Last Friday a started with 50gr. of Rye Flour +50 gr of water (tapwater boiled 5 mins) and cooled to 90 degs.
Next day i added 50gr. of Flour and 50 gr. of water ,mixed and sat in a warm place ! The next day i added 100grs. of flour and 100grs. of water ,mixed well and some time later noticed it rising almost double , thought i was going to put in a larger jar ! but it settled down . It never recovered again even after i fed the mixture (3) times at intervals of 12 hours ! I do see tiny bubbles and it has a nice smell but i thought it would start again to rise after each feeding . then in 6or 7 days have a starter for bread making ! Sorry for the long question , Any suggestions , Jerry Uhte Thank You !

Sorry for the long question , any suggestions ? Thank You, Jerry Uhte

Kaitlynn Fenley February 3, 2022 - 6:07 am

If you are using rye flour it might not have enough water. When I use rye flour, it’s a sprouted flour and it requires more water than a 1:1 ratio. I use 1:2 (flour to water) for my rye starter. Also, it sounds like you are not discarding… After the first feeding you need to discard before you feed it. For my rye starter I take 50 grams of the established starter, put it in a fresh jar and add 50 grams of flour and 100 grams water.

You also might be missing the rise? are you sure its not just rising and falling back down while you are not looking at it?

Kelsey February 18, 2022 - 5:29 am

Hi, there! Thank you for your info it’s very helpful I have a question about mold. Im a beginner and I’ve been doing my starter for a few weeks, I’m using spelt flour. I used a jar that was too big so the sides have developed a crust on them and they have black spots. The starter seems fine but I’m worried that the black spots are mold. It doesn’t seem fuzzy really so I’m not sure. Should I throw it all away and start over or just move my starter to a clean jar?

Kaitlynn Fenley February 23, 2022 - 8:07 am

If you have some fresh starter in the bottom of the jar, you can just carefully spoon a bit out and feed it in a clean jar.

Marg June 13, 2022 - 10:37 pm

Thanks for all your wonderful information! Are you familiar with Dr Stephen R Gundry’s “Plant Paradox” eating plan? It eliminates many grains that are problematic. Almond, Coconut, Sorghum, Cassava, & other flours are compliant. Have you tried sourdough with these flours?

Kaitlynn Fenley June 14, 2022 - 1:29 pm

hi there! I’ve heard of it, but I do not think fermented wheat is bad. Long, naturally fermented wheat is not a problematic grain. I have a recipe for gluten free sourdough starter linked above if you’re interested.

Priscilla June 14, 2022 - 9:49 am

Hello. I am just beginning a sourdough starter. I have tried twice with 50 g water and bread flour but each morning it had slight pink/purple spots just after the first day. I’m not sure what I am doing wrong. I used Bob’s Red Mill bread flour and bottled water the first time and filtered tap water the second time. Both times I had it in a plastic food storage container with a plastic lid. I am trying again with a mason jar and cloth cover. Do you think I need to feed it again after 12 hours?

Kaitlynn Fenley June 14, 2022 - 1:33 pm

It sounds like you were using a solid plastic lid… that and the plastic container were most likely the cause of your problems. Sourdough starters require oxygen, and should always be kept in a glass jar with a cloth covering. I bet you will have better results after switching. You only need to discard and feed the starter once every 24 hours.

Kari Bryant July 10, 2022 - 9:48 am

Hello, o have used the same starter for over 2 years, and today when I went to feed it, there is definitely mold on the side of the jar. There isn’t any in the starter itself, but I’m not sure what to do in this instance. Do I need to throw the whole thing out? I poured the starter out using the opposite side from the mold so it didn’t come into contact with it, into a new jar, but I’m a little afraid of the mold lol. Is it still ok to use?

Kaitlynn Fenley July 11, 2022 - 10:09 am

sounds like you did fine fixing it! It should still be okay to use as long as it was not black or colorful mold. I suggest putting your starter into a clean jar every other day.

Mick August 9, 2022 - 1:13 pm

Hello! Thank you for all the great information. I found your article because my starter (all purpose 1:1, smells like alcohol, and cover with paper towel and rubber band) had a dried out top that had bubbles, about a centimeter, but the mixture on the bottom was liquid and lighter in color with no bubbles. There wasn’t any discolored streaks or fuzz but the top was like one shade darker. Is this oxidation? Or the beginning of mold?
Thank you for your help!

Kaitlynn Fenley August 9, 2022 - 1:39 pm

Yes the top can dry out after 24 hours of no feeding. Sounds like you just need to remove the dry top, discard and feed it. Most starters are ready to use, 4-6 hours after feeding. When you leave it 24 hours, it can rise, fall then dry out on the top.

Kristi Robinson February 5, 2023 - 2:51 pm

Hi! I have begun a starter with organic all purpose flour, but I would MUCH rather use a sprouted rye like you mentioned. Do I need to start over, or can I just begin feeding with the sprouted rye: H2O, 2:1 mixture that you recommended?

Kaitlynn Fenley February 6, 2023 - 8:24 am

you can just switch your starter over to rye flour, no need to start over.

Dorota February 12, 2023 - 6:49 am

Hi! I was wondering what causes the red hue in the starter when using a 100% rye flour?

Kaitlynn Fenley February 12, 2023 - 6:54 am

Hello! Rye flour is usually light brown to very dark brown. Red is one of the primary colors that make brown. So pigments in the rye flour can make it take on a light reddish tinge when it ferments.

Bekah May 25, 2023 - 9:31 am

Yesterday I noticed white fuzz near top of sourdough starter jar. Also, looked like some green on side of jar where some starter had stuck. There was nothing on starter itself. I took small bit of starter and put into a new clean jar. So far not seeing any mold. Is this okay or do I need to start over? If it has mold will it quickly show up again?

April July 10, 2023 - 10:36 am

Great tips. Still need your expertise, I have a starter that has a hard crust on the top. Underneath it looks alive and when I feed it it keeps doing its bubbling thing but what is the hard crust and should I just throw it away ?

Kaitlynn Fenley July 10, 2023 - 10:48 am

That’s normal. No need to throw it. It happens when the top dries out.

Katerina Thomopoulou March 24, 2024 - 7:15 pm

Hi Kaitlyn! I’m on day 12 with my new starter and yesterday i skipped a feeding based on tips i found on tiktok. after about 48hrs since feeding, it had doubled and was already almost all the way back down. However, i noticed it was developing some faint white spots on the surface. not fuzzy, kind of like a thin film. is that mold? i discarded and fed like normal, but worried hahah. If it was mold, and there’s still mold in it, will i know? Will it become visible or affect how it’s rising? Is there a chance it goes undetected?

Kaitlynn Fenley March 25, 2024 - 8:18 am

It probably wasn’t mold! Just keep feeding and discarding like normal and it should be fine.

Lisa June 25, 2024 - 5:03 pm

I accidentally doubled my flour to feed a new starter . What should I do ?

Kaitlynn Fenley June 26, 2024 - 9:40 am

Just roll with it. Add a little water to make it thinner if you cant stir it, and then keep feeding as normal.