4 Key reasons why your sourdough bread is flat (2024)

“Everyone has what it takes
to make great sourdough.”

Making your own sourdough bread is a great privilege. I find it’s cathartic and artistic; a mystery and a science. It can also be a great disappointment. Your much-anticipated loaf can look incredible going into the oven, but when you pull it out, eager to cut it open, you discover that your precious sourdough bread is flat. Sometimes you know something has gone wrong well before the oven too. Not only is your loaf flat, but it can make you feel flat too.

I know. I’ve been there.

Can I let you in on something? Behind every perfect Instagram loaf and Facebook-famous sourdough post are 5, 15, even 50 sourdough bread fails before it. Yes. It was 18 months of flat bread for me, and the rare but occasional one since. I have been baking and hacking sourdough bread for more than a decade and a half now.

Sourdough bread is a natural, yet reasonably predictable, process. Relying on wild yeast to rise to each loaf, you just need to understand how this living, breathing, fermenting wonder works. That’s why you’re here.

Sourdough takes longer than yeasted bread and can have a few tender pitfalls. But when you know how to navigate them, making sourdough bread is much tastier, better for you and can be much more flexible than making yeasted bread. Sourdough loaves even look better. But that’s my biased obsession!!

While sourdough bread does rise in the oven, by nature, it doesn’t rise as much as bread made with bakers yeast. When your beloved sourdough bread comes out of the oven flat, knowing why can be tricky to work out.

Sometimes it rises a bit, others, it just doesn’t rise at all. A flat and dense loaf of sourdough is not the good kind of flat, not like a floppy tortilla, no…. 🙁

It’s more like a flat brick.

Or sometimes, a half-flat brick.

The top half is semi bread-like but the bottom half… well, it’s like a surfboard.

Something went wrong.

Every issue with flat sourdough bread will fall into one of these four categories:

1. Flour issues
2. Exhausted or weak sourdough starter
3. Under or over-proofed dough
4. Your baking process

Let’s go through them one at a time. It’s important to understand each one because your bread might be flat this time due to just one, or a combination of them. Next time though, your sourdough bread might be flat might be for a completely different reason.

You may like to bookmark this page to refer to as often as you like, as you walk out the magical sourdough journey.

Let’s hope though, there won’t be a ‘next time’. 😉

Flour issues

The Number #1 Reason your sourdough bread might be flat is using the wrong flour.

Bread flour
Bread mix, all-purpose flour, self-raising flour or cake flour can produce undesirable results when making sourdough. They are purposed for cakes, slices, muffins, and other cooking. And when it comes to bread, they are only useful for making yeasted bread. Make sure you use flour from our list of recommended bread flours. You should be able to get some at your local supermarket.

Otherwise, simply choose a flour that has 12.5-13% protein. If it has even just under 1% less than this, you will notice it in your bread. Adding 1 egg in place of an equal portion of the dough’s water measurement can make a massive difference in this case. It also makes the loaf more tender which is a bonus! Weigh the egg, subtract the same weight from the dough measurement. Or, an easy way is to place a bowl on the scales and press tare to bring the scales to zero. Add the egg and then pour in water until the scales match the recipe measurement for water. Voila!

KEY TIP: Protein gives the dough enough strength to rise a loaf of artisan bread without adding yeast. Without enough protein, you may get a bubbly starter but your loaf will be too relaxed and, like a weak muscle, unable to do any heavy lifting.

Bodybuilders rely on protein to build their muscles, so do the gluten bonds in sourdough!!

Bread mixes don’t require as much protein to be inherent within the flour. They’re designed to be used with bakers yeast and the protein content of the flour itself is often around 8%. The protein level written on the box is for the entire bread mix, not just the flour. So, sometimes the box may say 13% protein, but that’s not in the flour on its own, it’s including all the add-ins. Seeds can boost the protein count to 13% but seeds don’t make the dough strong enough to rise your bread. The flour does. So it’s the protein content of the flour that matters.

Flour types
Spelt and rye flours have enough protein in the flour to make great sourdough bread, but they naturally produce less rise. This is not a fault but a characteristic of these two flours. You will still get a semi-open crumb and a very likeable sourdough, but if your heart desires a taller loaf, try using 50% wheat flour with 50% rye flour or 50% spelt flour to give a little ‘boost’ to your sourdough.

Old flour
Sometimes flour is not stored correctly or has passed the use-by date. This affects the nutrient activity of the flour causing your sourdough to struggle because there is not enough ‘fresh food’ for it to activate. Try to eliminate all the other possibilities before you throw your flour out. But I suggest buying some fresh flour and seeing if that solves the issue for you.

Exhausted or weak sourdough starter

If you have used fresh, suitable bread flour and your precious loaf of sourdough bread is still flat and dense, the issue may have been with your sourdough starter.

Sourdough starter needs to be turned into dough the moment it is has doubled. This is when your starter is at its strongest point, and therefore able to rise a good loaf of bread.

This should occur after your most recent feed, assuming that your sourdough starter is healthy and active. If you are storing your starter in the fridge, rather than on your kitchen bench, I recommend a 2-Step feeding process. One to revive your starter as it comes to room temperature and another to bring it to double in volume.

If you are following our Pantry Sourdough Starter process, where you don’t have to care for your sourdough (ever!) unless baking, dough doubling will occur after FEED 3.

My key tip is this:
Whatever your starter looks like when you add it to your bread dough, is what your bread will look like when you bake it.

If your sourdough starter has no rise or structure (is runny) ~ your sourdough bread will also have no rise or structure. No matter how perfectly you bake it,

If your sourdough starter has expanded and is able to hold that structure ~ your sourdough bread will expand and hold that structure too!

It’s as simple as that. Truly.

So long as the proofing processes of your dough goes OK, what you put into your sourdough dough, you will get in your loaf of bread.

Let’s talk through the various issues with sourdough starter.

We’ve covered flour, so let’s cover time and temperature ~ the other two vital ingredients in making sure your sourdough bread isn’t flat.

Exhausted sourdough starter
When the environment in your kitchen is warm, your sourdough starter may double faster than expected. You may not be home to see this happen and/or not paying attention, expecting to leave it for a longer time.

If the sourdough starter is left too long in a doubled state, it will run out of food to grow any more and get hungry. What happens then is the structure begins to collapse, causing the starter to deflate or go back down. You may notice this especially if you gently tap your jar on the kitchen bench.

You can also tell because the mix seems wetter and more sloppy than when you fed it last and instead of being a strong web of puffy air pockets beneath the surface, it is starting to become liquid.

Another sign is that the volume of your sourdough starter is the same as it was when you first mixed it. It was thick then, now it’s runny. This means it did puff up but when too far and has now deflated liked like a leaky balloon.

This is your starter telling you that it’s healthy! However, it’s been working so hard, growing all day in the warm air, it’s now exhausted and has no energy left for bread. Your starter will need feeding and left to double again before it can be used. Use it when its doubled, not before and not after.

If this happens to you and you don’t recognise before making dough, your bread will tell you once it’s baked. The loaf will be tasty but flat. If you think this is what has happened to your starter and you haven’t made bread with it yet, see our rescue for deflated sourdough.

Sometimes, in warm weather, if you aren’t at home or you are busy, you won’t see the starter double and deflate again. It can look like it hasn’t risen and so, even though it’s been left too long, you may instead think to leave it longer. This is a risk in warmer environments. Keep your sourdough somewhere you can see it and see our rescue for deflated sourdough for other helpful hints.

If you think this process might be contributing to your flat sourdough, you can learn more using my Sourdough Journal (on Etsy). Track sourdough starter feeds and discover how long your sourdough takes to double at different temperatures. Filled with advice that works in all seasons plus 15 worksheets to choose from to record and track your own sourdough cycle, and learn how to make your sourdough bread rise in the oven every time. Includes done-for-you baking schedules.

The journal is under our new brand specially for foodies: Enfoodiest

Weak sourdough starter
Sourdough starter that doesn’t rise, is too weak to rise a loaf of bread.

Weak sourdough starter can look just like a deflated and exhausted sourdough starter. It looks like the volume hasn’t changed since you last fed it. The difference is, this one didn’t double and deflate. It just didn’t double at all. You will be able to tell because the surface will be dense with few, if any bubbles.

The reason ~ you’ve perhaps made your sourdough from scratch and it needs more feeds and more time to become active. It may also need some warmer temperatures to help it along.

If this process exceeds 10-14 days without your sourdough starter doubling, it may not ever become viable. Consider buying a sourdough starter that is already active and save yourself the hassle and heartache of baking sourdough bread that comes out flat. I had plenty of heartache in the beginning!

If you bake sourdough once a week (or less regularly) and don’t want to feed a sourdough starter between bakes, try our Pantry Sourdough Starter. It’s 100% authentic sourdough starter that you can store in your pantry without maintaining it to keep it alive. If you want a way to feed your sourdough starter less often, browse low-maintenance sourdough starter.

If you are using our Pantry Sourdough Starter process, and your sourdough starter isn’t growing, it probably needs more warmth. See How to keep sourdough warm even in winter for some simple hacks that will encourage your flakes to grow!

Under or over-proofed dough

You can get the right flour, grow a kickin’ sourdough starter, form a brilliant dough and loose it all in the rising and proofing.

Sourdough bread has two rises. The second shorter than the first.

Under-proofed sourdough loaves
Dough that’s not left long enough for either of the two required rises, will result in sourdough bread that’s flat.

The length of time for the first rise will usually vary from 4-12 hours.

This time range is not a ‘however long it suits you’ suggestion. It’s a ‘however long it suits your dough‘ guide and it depends on whether or not you kneaded your dough and how warm (or cool) your kitchen is at the time.

Not allowing the dough to double during the first rise can be one reason your sourdough bread is flat and dense. Not giving it long enough to ripen during the second rise (proof) is another. In both cases ~ your sourdough bread was not mature enough to bake.

First rise: You can tell when it’s ready because the dough has doubled or is noticeably a lot bigger compared to when you made it. When you shape an immature dough, you will find it’s not all that puffy, may snap or resist when first being shaped.

If you are home during the first rise, you are free to keep an eye on the process, ready to shape your dough once it has doubled. If you are not home or available, you are going to have to know how long it will take to double so that you can make sure you are available when the dough is ready. Your dough won’t work to your time schedule unless you know how to hack time and temperature to make it work for you.

Second rise: It is unlikely your loaf will double, but it will puff a little and slightly bounce back when lightly poked. Fast return on your finger’s indent means it’s not yet ready. If it doesn’t bounce back, the opposite has happened ~ the dough has gone past its peak and is becoming tired. It may bake well but won’t rise in the oven. For more information and rescue for over-proofed sourdough read How to tell when your sourdough is ready to bake – The Poke Test.

When dough is under-proofed, what happened?

You may have impatiently cut the time short or worked with a cool kitchen. In both cases, the dough needed to be left longer OR, the temperature of the room needed to be increased. Don’t do both. Warm temperatures shorten rise times, cooler temperatures lengthen them.

Your dough was simply not ready to be cooked.

My process uses long rises, being a no-knead dough with no experience required process. It’s designed to be easy and has inbuilt recommendations for time-frames at various temperatures. It can be worked easily around working or busy family life. I love sourdough and want you to love it too and avoid the many pitfalls of making it.

Over-proofed dough
To state the obvious, this is the opposite of under-proofing your sourdough.

When sourdough reaches its optimum growth, it needs to be shaped after the first rise and baked after the second rise. When this doesn’t happen, in both instances, your precious sourdough is exhausted from all it’s growing, and like a tired, hungry 2-year-old, it has a meltdown. Literally. The internal structure holding all the air pockets and beautiful would-be crumb, begins to collapse.

What happened?

Your dough was left too long and/or your kitchen environment was warmer than you thought. It grew faster and stronger than you were available to meet its need by moving on to the next step. It ran out of fuel waiting and deflated like a balloon. It can sometimes be as simple as not turning on the oven in time so that its ready when your bread is.

If you are proofing at room temperature, turn your oven on after you shape your dough, not when the dough is ready to bake.

What it looks like:

First rise: When you do move on to the next step, shaping your sourdough loaf, the dough doesn’t hold its shape. It’s slack and wetter than expected. It may even be glossy and wet looking.

If you bake it, your sourdough bread will taste great but the texture will be dense and chewy. Your sourdough bread will be flat. If you think your sourdough dough is exhausted from the first rise, see the ‘dough’ section in our rescue for deflated sourdough for a suggested way of rescuing your efforts.

Second Rise:
It is almost impossible to over-proof your dough when using the Refrigerator Method and that’s why I use it – it makes the sourdough journey so easy. But if you skip the Refrigerator Method and proof at room temperature and your dough goes past maturity without being baked, it will exhaust itself.

It does all its rising on your bench-top and there is no energy left in the loaf to rise inside the oven.

You can tell when your loaf is ready, under or over-proofed by using the Poke Test. If your sourdough is over-proofed, the loaf will not bounce back when gently poked.

Make sure, if you’re not using the Refrigerator Method, that you’re familiar with proofing your sourdough at room temperature and the Poke Test so that you know the precise moment your dough needs to be placed inside that piping hot oven of yours!

If you want to learn more about the affect of time and temperature on proofing and sourdough, I’ve put together the Sourdough Journal for you! You can track sourdough starter feeds to see how long your starter takes to double at different temperatures.

Filled with advice that works in all seasons plus 15 worksheets to choose from you will get to know your own sourdough cycle, and make sourdough bread that rises in the oven every time. Includes done-for-you baking schedules for winter, summer and mid-season. Proof like a Pro!.

Your baking process

Loose shaping
Converse to natural logic, your dough likes to be tightly shaped so it can burst when it’s in the oven. Think of it like a strong, tense leg muscle launching you into the air with a jump vs weak, lazy, floppy muscles. You won’t get the same height. Your sourdough bread is the same. It gets height when it’s tight and strong. When you do your Pull & Stretch it’s like wrapping a present tightly. Lift the edge of the dough towards the ceiling and fold down into the middle. Repeat, overlapping the last fold. Do this 12-14 times or until your dough is tight and it’s difficult to do this anymore. Then do 1-2 more!

Baking method or inexperience
While baking inexperience won’t produce dense, flat sourdough, it can affect how much your loaf rises. Simple hacks like covering your loaf with a large cake tin or adding a tray of boiling water in your oven can improve both the colour and the size of your loaf.

For specific tips, based on your method of baking see:

Baking your sourdough bread using a Dutch oven or casserole dish
Baking your sourdough bread using a pizza stone
Faking it – Baking your sourdough without a dutch oven or pizza stone

If this post helped solved your flat sourdough bread issue, let us know by commenting below! What tip made the difference for you?