The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Loaf cracks on the bottom during oven spring

sasomao's picture

Loaf cracks on the bottom during oven spring

Hi all,

So, I'm beginning to bake with natural levain and I've the problem given in the subject (which I never had with dried yeast).

I'm following the receipe given in Hamelman for the Vermount Sourdough, using the levain with 125% of hydratation.
What I do, is that I make the final mix at ~7PM, I fold twice, and give the final shape at ~10PM (oval loaves). The temperature during the process is 22-23 C.

I let the loaves raise ~1hr at 22C seams up, and then put them in the fridge at 11PM (temp 10C) seams up. They are lean on baking paper and covered with plastic film.

At 8.30AM the next morning I remove them from the fridge, let them "warm" at room temperature for 30-45min, I turn them in such a way that what was the bottom becomes the top (that is, they are baked with seams down), score them and bake (250C, steam).

What happens it that the loaf is not fully developed at the top, but it craks on the bottom instead, during the oven spring. I can attach picture, if you want (and if I discovered how to do that!).

When that happened the first time, I though it might be due to a gradient of preassure (sorry, I'm a physicist :-) ) in the loaf, with the part that stayed on the bottom for the whole night more dense (and/or humid) than the top. So today I made again two loafs, but this time I left one of the two with the seams down while I turned the other. The outcome is that both of them cracked on the bottom :-)
I don't think the problem are the seams not well sealed, as the cracks do not happen in correspondence to the seams lines. 

Hence, it seems I've no idea of why this is happening, and suggestions are welcome!!




amolitor's picture

Generally if the loaf blows out at the bottom you're underproofed. After final shaping, you need to let the yeast and dough get to the right place, otherwise the yeast will get a little too crazy in the oven and blow the bottom of the loaf out. Do you poke-test? You should poke the dough with a finger, making a hole perhaps 1cm deep. This hole should fill back in very slowly, so that after 30 seconds or so there's just a dimple. If it doesn't fill in, you've gone too far! Bake it very hot to try to save it. If it fills in faster and more thoroughly, it's not ready to go in.

I poke the dough pretty often as it proof (so, after you pull it from the fridge) so I can "follow along" with the progress.

What shape are these loaves? 30-45 minutes feels a little short for warm-up time, but obviously that depends on the shape. A huge boule will warm up much more slowly than a baguette!

The other possibility is that you're slashing poorly, maybe. It might not be letting off enough of the pressure at the top of the loaf. I'd make sure I was adequately proofed first, though.


sasomao's picture


thanks for the answer. 

I try to poke them, but that is a tecnique I've just learnt, and I guess I need to calibrate and understand what is the right reaction from the dough. (btw, do you know of videos that show what the good response of the dough should be?)

So if they need more proofing, it means that I've to begin earlier the day before, or put them in the oven later, which I'd avoid because I've to go to work.
I already give them ~ 4.5hrs at 22C and 8hrs at 10C !

The loaves are ~1lb each, not that big, oval shape. (I'm attaching links to the top and bottom of the loaves).






amolitor's picture

Could you get them out of the fridge earlier in the morning? This gives them less time being retarded, but more time proofing at room temp.

You could also, I think, reduce the oven temperature a bit. I think 250C is about 482F, which is hotter than what *I* use, but cooler than a commercial bread baking oven (I think). I am pretty sure that a hotter oven will give a more vigorous kick of yeast activity, though.

If I were you I'd try getting the out of the fridge an hour earlier, first, and if that wasn't enough, I'd try that and then reducing my oven to 230C, and then.. well, hopefully that would have worked! That's just my idea for what might help, though, not a guaranteed solution of anything.

jcking's picture

Naturally fermented dough doesn't need to be shaped as tightly as those with commercial yeast. Wild yeast dough favors gentler handling.


ehanner's picture

I'd agree with the other comments but just add this. It doesn't look like you are actually proofing much after shaping. Depending on your starter and how active it is, the fermenting might not be proceeding as much as needed. I'd say look at your dough in bulk ferment first. If you see bubbles near the end of the ferment period on the side of a clear fermenting bucket or the dough looks like a sponge if you cut it open, then it should be about double in volume. Then when you shape and proof, watch for the volume increasing about 50% before you refrigerate. If you do that, you can bake right out of the fridge with little warming time. The time needed to heat the oven and stone is more than enough. I think what is happening is the top is setting first and the bottom sides don't dry off until later. This would be especially true of the inside sides between the loaves when baking two loaves at the same time. Hope this helps.


sasomao's picture

Hi all,

I'm digging up this thread (last few months I haven't had the chance to make bread as often as I would have liked, even though I kept alive my sourdough, which is now 9 months old :-) ) because I'm still having this problem of the cracks on the bottom.

 The difference is that today and yesterday I got the problem even without overnight proofing. I'm still following Hamelman recipe for the Vermont Sourdough. I had a 3 hrs raising + 2.25hr final proof. Here in Amsterdam it was quite hot, with temperature around 27-30C for the whole time (this is why I reduced the final proof time by a tiny amount wrt the receip).

The final result was again two oval loaves (one yesterday and one today) with cracks beneath.

I wanted to ask you to the gurus of the forum it they think the reason can also be one of the two below:

1) Scores on the loaves not deep enough (I use a scalpel, held vertically wrt the surface of the loaf, two strait cuts along the loaf axes, with an angle of ~30 degs). They are ~0.5 cm deep.

2) My oven is too small to accommodate a baking stone, thus I put the bread directly on the baking thin, which is left in during the pre-heating. Can it be that, being metallic, it becomes too hot, and when I put the loaf inside the oven, the sudden change of temperature in the bottom makes it too expand too quickly there and crack?

I don't think that underproofing can have been a reason today, with more than 2hrs of final proof and room temperature above 26C.

What do people think?