The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Explosions in sourdough loaf

LawrenceL's picture

Explosions in sourdough loaf

Hi there

I've been making sourdough since last February, getting gradually more consistent, but lately suffering from these explosions in the bread. The only thing I've changed is putting some quarry tiles in the oven- could it be they are producing TOO MUCH heat? I thought the idea was to get as high a temperature as possible? I'm using a conventional fan assisted oven and putting it up to it's maximum 250 centrigrade (though my oven thermometer at the front never reads above around 230. I've read a number of posts about this problem and there seem to be so many variables I don't know where to start. Any ideas? Thanks in advance. Lawrence

LindyD's picture

That's happened to me when I've underproofed my SD boules.   I find it tough to judge proofing when using a brotform or baneton because of the shape of the form and the variations in temperature between top and bottom, especially if the dough has been retarded overnight.  

With a batard, it's easier for me to feel the dough since I can get my hands under and around it.  Still haven't quite figured how to do that out with boules in brotforms. 

Wandering Bread's picture
Wandering Bread

Yep, that looks underproofed. I don't know what climate you're in but I've noticed lately that with the cooler temperature outside, my room temp is also a bit lower. A few degrees can make a huge difference with proofing times. You're probably just another hour or two away from a perfect oven spring. Good luck with the next one! -Ryan

LawrenceL's picture

Thanks- I'm in East London and yes, it does seem to be happening more since we've moved into winter. I've been experimenting with leaving the starter out between refreshments as it seemed it was having to work too hard (though this is another issue). Would you suggest a bit longer out before retarding then (it's going into the fridge overnight). Can you explain why you get explosions with under-prooved bread?

Janetcook's picture

In cooler weather I hold back longer before putting my doughs into the refrigerator to ferment overnight.  This boils down to about a 25-30% expansion in the dough.  This way I know the yeast are awake and doing their thing :-)

Different doughs vary so you have to watch the dough and not the clock to judge when to put it into the chiller.

If I have jumped the gun I know it in the morning by how the dough feels.  Easy to fix- just more time at room temp. prior to shaping and proofing.  I try not to go in the other direction - Not as easy to 'fix' an over fermented dough.... :-( 

Good Luck :-)


Mini Oven's picture
Mini Oven

by baking too early,  there is too much trapped steam and uncooked dough and not enough room under the crust for the baking dough to stay under control.   The small set crust will burst.  The energy finds the weakest crust spot and then "explodes" into it, or out beyond the crust.  By letting the dough proof longer and rise more there is more surface area and more control over the expansion.  

I like to rest my hand on the dough and feel the gas under the surface pushing against the skin of the loaf.  If resistance is high,  and skin feels very tight and too solid, it needs more proofing.  If there is light resistance, I bake it.  No resistance is on "the edge" of being over-proofed.  

LawrenceL's picture

Thanks all for your helpful and thorough replies...

So, I tried leaving the formed loaves overnight in bannetons (about 6.5 hours) in the fairly cold kitchen (prob around 10 degrees c, rather than straight into the fridge to retard. Thought I'd take the risk and find out what over-prooved might look like.

I tried the finger test in the morning and it left a small indentation that didn't come all the way back again. As a relative newcomer, I couldn't pick up on your more subtle methods, Mini oven!

They did feel a lot better than previous times - less solid and more airy feeling. However, I noticed they lost some of their shape on turning out and some spread and lost their height. AND I still got explosions- slightly less than before but still much more than earlier in the season.

Is this spreading a sign of overprooving? Could the explosions be a result of something else? Or do I need to prove longer before shaping- from start to finish was about 5-6 hours with 3 kneads and 2 folds?

Any further thoughts?


Mini Oven's picture
Mini Oven

a crumb examination should tell you.  

Large bubbles?  When you look at the dough between the bubbles, how dense is it?

Cold weather and sourdough means longer proofing times.  Much longer than 6 hrs.

Spread out might mean you need to do more folding of the dough.  In your temps, I wouldn't even do a first fold until I see a little rise in the dough.  That might take 3 to 6 hrs or more.

Wait... "start to finish was about 5-6 hrs with 3 kneads and 2 folds..."    Can you explain more?    What are "3 kneads?"      

LawrenceL's picture

Hi again

Here's my schedule:

I mix starter with warm water and then add my flour.Leave for 20 mins. Add salt. Leave 15 mins. K1. Leave 15 mins. K2. Leave 15 mins. K3. Leave 40 mins. Fold 1. Leave 40 mins. Fold 2. Leave 30 mins. Shape and put into bannetons. Retard overnight. 1 hour at room temperature before baking.

As I say this has been working well over the year since February but perhaps, as you say, with drops in temperature this is too short now.

By knead I mean a roughly 20 second period of lifting and stretching each 'corner' of the dough and rotating the bowl each time. I'm working with about 8 loaves at a time now so it's a pretty big load of dough.

Sorry if I'm not using correct technicalities!

Trouble is I'm doing all this in the eves and baking before work so unless I want to stay up till 2am, I'm not sure I can increase my prooving time. BUT I did leave them at a fairly low room temperature all of last night and yet they still seem, you indicate, under-prooved (yes the crumb was quite dense, as you can see here:

Perhaps next step is longer prooving (I'm trying some warmer places) before shaping and a bit more stretches in the folding process.

thanks again for thoughts.