The Fresh Loaf

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Irregular holes in Sourdough bread - help please :(

bakeyourownAU's picture

Irregular holes in Sourdough bread - help please :(

Hey everyone,

How's it going? I hope all is well.

I've been recently running into an issue regarding oven spring and irregular holes with my sourdough bread.

I usually bake with a cast iron dutch oven and usually get very good oven spring and consistency.

Recently, I've tried to start utilizing my pizza stone to bake multiple loaves at a time.

To first test it, I've been baking some loaves for the last few days, but have been having some severe problems with my bread.  My starter is very active, usually overflows from the container in about 8 hours. The recipe I use is as follows:

800gr of unbleached strong bakers flour

200gr of wholemeal

200gr of rye sourdough starter

20gr of salt

700gr of tepid water


I start off my feeding my starter the night before using a 1:5:5 feeding cycle. So 25gr mature starter, 125gr organic rye flour and 125gr water. I also start my autolyse the night before by mixing my flours and water and letting it sit for about 10 hours. In the morning, I test it by pulling a window (window pane) and it passes everytime. 


In the morning, I mixed in my starter and salt at the same time to the dough and bulk ferment for 5 hours, at the moment my kitchen is about 21 degrees celcius. Within the first two hours of bulk fermentation, i stretch and fold 4 times. 

After stretching and folding, I shape my loaves into boules and place them into the bannetons, and proove them for about 3-3.5 hours at room temp. In the last 40 mins of the proving, I place them in the freezer as this makes scoring much easier. 

In the last hour of proving, I switch my oven on to its max (250 degrees C) and place my pizza stone in it with a cake pan that has lava stones in it underneath the pizza stone on the oven base.  I then score my loaf and put it straight on the pizza stone and put in about 500ml of water on the lava stones and immediately close the door. I bake the loaf in this way for 20-25 mins, then open the oven door to dry out the oven and take the lava stones out. I then bring my oven down to about 220 degrees c and bake my loaves for another 10-15 mins. 


Here are the pictures of my loaves (I'm not sure why the first loaf is coming up upside down as I've tried uploading the picture 3 times) :

Anon2's picture
Anon2 (not verified)

Surrounded by a tight crumb points to under fermented. You need to increase the bulk ferment time. 

I think the very long autolyse can make the dough feel ready when it's not. For an 80% bread flour dough 30-60 minutes is ample. It's done to allow the flour to absorb the water before the salt goes in. The aim of the game is not a windowpane. We look for that in the final dough. 

How mature is your starter when used? If your kitchen is 21°C in the day time then I assume it's colder at night. With your starter build being 1:5:5 plus it's not so warm it might mean your starter isn't being used at the optimum time.

So it's either your starter and/or it simply needs a longer bulk ferment. Perhaps you can find a way of fermenting at warmer temperatures. Failing that then for longer. 

bakeyourownAU's picture

Hey Abe,

Thank you very much for your reply. A wealth of knowledge here. I truly appreciate it. 

I'll try the shorter autolyse. The starter is used about 8-10 hours after its feed. So I'd usually feed it at about 8pm the night before, and then use it at around 6-7am the next morning.  

Would you recommend utilising the oven by putting a small glass of boiling water in there? Seems like I may need to revert back to that. 

The oven being used is an electric convection oven.  

Would you also think the pizza stone is too thin and cant retain enough heat?


idaveindy's picture

(edit: apparently doubled with Abe.)

Welcome to TFL !

1. what kind of oven? gas? electric? convection(fan) ?  

If it's gas, go back to the D.O., or use an inverted pot on the stone, and forget the steam pan. Steaming a gas home oven and trying to  bake a _bare_ loaf with gas just does not work.

2. Where are the heating elements if electric (fan or no fan) ? Top? Bottom? Hidden bottom? Back wall ?

3. Never put the steam pan directly on the bottom surface of the oven. it robs too much heat if it's a gas oven or is using a "hidden" bottom element.  It needs to go on a rack, below or above the rack upon which the stone rests.

4. 500 ml of water is too much. Even worse if it was not boiling, as it would rob heat from the oven. 250 ml of _boiling_ water would be better.  

The crust in the first photo hints at too much steam.

5. 100 degree C steam is cooler than the 250 C oven. So much "cool" steam, from 500 ml water,  is  rising up and _cooling_ your stone. You can see this in the pale bottom crust. It's paler than the top crust.

6. At first glance, your crumb looks under fermented, but it is also clearly under-baked on the inside, due to the "cool" oven. 

Gonna go out on a limb here: it's possible that the dough itself was not actually under-fermented, but only _looks_ that way because the loaf is under-baked.  (Your answer to the next question will help resolve this possibility.)

7. Did this same formula, ingredients, procedures and timings (levain build, autolyse, ferment, proof) result well with the dutch oven?

added: I concur with Abe about excessive autolyse, unless it was done in refrigerator. 

Good luck, and bon appétit !

bakeyourownAU's picture

Hey Idaveindy,

Thanks for your reply and sharing your knowledge.

In terms of your questions:

1. The oven is an electric convection oven with heating elements on both top, bottom and the back of the oven where the fan is present. The back element though doesnt work when you have the top and bottom elements on. I dont also have the function of turning off the fan.

2. In terms of the steaming pan, I've tried using a baking tray right on the bottom of the stone, but I think it may have been either too many rocks/steam, or the baking ban was just too big blocking off the heat from underneath. I'll try use a small cake loaf pan with the rocks in them below the stone now. 

3. I'll try adjust the steam to 250ml and let you know of the results

4. The same formula has worked in the dutch oven, but with the only different being shorter autolyse, and also proofing being done in the oven with either the oven light turned on (If I can get it turned on, sometimes randomly turns on and off :)) or with a small milk pitcher full of boiling water. Below is my loaf in the dutch oven (last picture), with a 30 min autolyse and bulk fermented in the oven with the boiling water. Also, I added some more pictures with a second loaf from the problematic batch. In this one, the its the exact same formula above, but instead of steaming, I put a glass bowl over the loaf, seems like I got great oven spring. 


Loaf done with a 30 min autolyse, bulk fermented and proofed in the oven with some boiling water in a pitcher, and baked in a dutch oven. Bulk fermentation time is about 4-4.5 hours with 3-3.5 hours of proofing time. 

idaveindy's picture

Yeah,  bare loaves in a convection oven are problematic.  Because of the air currents, the crust gets done before the inside.  So you need the D.O. or the inverted bowl if you use the fan.

If you can use the bottom element only, and no fan, then a bare loaf, steaming from a pan, is possible.


bakeyourownAU's picture

I think I can use the bottom element only, but would the oven reach up to its target temp? I also dont have any issues with my normal yeasted loaves though. Only with the sourdough ones. Also, would you say the pizza stone may be too thin compared to a normal baking stone which is why enough heat isnt present?

idaveindy's picture

> I think I can use the bottom element only, but would the oven reach up to its target temp?

Yes, it should. You could also try this: use both top and bottom during pre-heat, and switch to bottom only for the bake.

However, bottom only  heat with the fan on is still going to dry/bake the crust too soon.  If you can never turn the fan off, either the inverted bowl or the DO will be necessary. 

>I also dont have any issues with my normal yeasted loaves though. Only with the sourdough ones.

I think sourdough behaves differently in the oven versus yeasted. also pan loaves versus free form. But my responses here are based on the photos and your descriptions.

>Also, would you say the pizza stone may be too thin compared to a normal baking stone which is why enough heat isnt present? 

Maybe. But the excess water and steam right under the stone is the main culprit. Steam is H2O, while air is O2 and N2.  add up the atomic weights. Steam H2O is lighter and rises, so you have cold(er) 100 C steam cooling off the 250 C stone.

Excess steam is a real thing, it really cools down an oven. Typical newbie problem here on TFL. Not pre-boiling the water is also a typical mistake, as getting the water up to temp, from 21 to 100 C/liquid also robs heat.  Going from 100/liquid to 100/steam robs enough heat. having first to go from 21/liquid to 100/liquid robs even more.

Then the 100 degree steam continues to rise in temp ("super-heat") as the previously 250 degree stone and air come down further in temp giving up thermal energy.

You can tell that a combination of convection air currents and cooled off stone are in effect by the paler lower crust.

Fixing the excess steam problem is cheaper than buying a new stone.

 But, you're the boss of your kitchen, and experimenting is fun.  So tinker as much as you are inclined. "More than one way to skin a cat."



bakeyourownAU's picture

Hey Idaveindy and TFL,

Upon my initial fail, I didnt some experimentation today and baked up three loaves. 

The formula used is for all three loaves is:

300gr of Rye Starter

1200gr of Strong unbleached white flour

300gr of wholemeal flour

1200 gr of water

30gr of salt


The following are my temperatures for ingredients:

Initial EDT: 30 degrees C

Pre ferment (fed at 1:1:1): 18.9 degrees C

Flour: 18.3 degrees C

Room: 17.8 degrees C

Water: 45 degrees C


I first did an autolyse my mixing the flours, water and starter for 30 mins. I was normally aiming for about 70-75% hydration but did a miscalculation at that moment which resulted in an 80% hydration. After the autolyse, I mixed the salt without adding any more water and did its first folds. Every 30 mins for a total of 2 hours, I did 4 turns in total, and bulk fermented for 3.5 hours. The dough went approximately 1.5 times its size and was quite 'billowy' and gassy by the end of it with fermentation bubbles coming about.  After bulk fermentation was complete, I did a bench rest for 20 mins, and then shaped the doughs and placed them into their bannetons and proved them for approximately 2.5 hours with the oven preheating with the stone in it and a tray on the bottom rack. After proving, I put loaves 2 and 3 into the freezer for 30-40 mins to firm up to make scoring easier.  

Loaf 1 was put in the electric convection oven with no lid or covering, straight on the stone, and 250ml of water put into the bottom tray to make steam. The lowered steam didnt really have any effect, and regardless of the steam, the loaf still got an early crust. 

The second loaf was pulled straight out of the freezer, scored and onto the pizza stone with a glass bowl on it. It had much better oven spring than the first one and a great crust. I believe it could have had much better oven spring, but was constraint to the curves of the bowl. If a dutch oven was used, it would have been even bigger.

The third loaf was a batard, and wanted to grow. But because it was constrained by the side of the glass bowl, it was not able to rise as it wanted. I think it would have been a huge loaf it it was put into a dutch oven. The top sides of the loaf were touching the curved sides of the bottom of the bowl (that was inverted on top of the loaf).  

Muddy Gardener's picture
Muddy Gardener

Thanks for posting the pictures of how your loaves differed depending on different baking treatments.   Fascinating!