Reducing Oven Spring / Underproofed?
Hello!
I've recently switched to a commercial ABS deck oven w/ steam injection, and have been experiencing an unexpected result in the sourdough bread I've been baking. The breads seem to be expanding too tall in the center along the score. I generally bake 900g batards with a single slash. I never had this issue using a standard combo cooker/dutch oven process. I'm wondering if the consistent heat from the commercial oven is actually less forgiving then my dutch oven trials, and the breads are actually under proofed (too much available yeast upon baking). Has anyone else ever experienced this? For more context:
Settings:
Top Heat: 480f
Bottom Heat: 460f
Steam: 6 seconds
15 minutes steam - 20 minutes without steam
I am looking for a more consistent shape. I'm wondering if there are also some shaping / stiching woes at play here as well. I often stitch up my breads in the bannetons before overnight cold proofing. Wonder if I'm wrapping them too tightly. I generally mix at 80% hydration, with 3 S&F.
Thanks!
Pictures would help.
Maybe check these previous threads on deck ovens with top heat, one might match up with your situation.
http://www.thefreshloaf.com/node/64854/deck-oven-problems-steam
http://www.thefreshloaf.com/node/63133/need-some-doctoring-please
This was after the initial 10-15 minutes during steam. You can see how the center is expanding quite high (well beyond the ear). This is undesired.
A0F0B711-D186-45BD-ADDF-57D722149996.jpeg
I'm still not fully understanding your situation because I don't know what your loaves previously looked like, nor why expansion "above" the ear is bad.
I will share some concepts about the challenges of baking bread with "top heat".
those are explored in the two threads (posts and comments) linked above, and here
http://www.thefreshloaf.com/node/65316/new-oven-build-preliminary-results
Generally, with bread, you want top heat _off_ so that the top crust doesn't set too soon, and so that the upper inside doesn't cook before the lower inside. Then towards the end of the bake, some people turn on the top heat for 1 to 2 minutes to brown the crust.
In kendalm's thread on his "new oven build" thread, he put in a raised floor to keep the bottom of bread from burning.
If you use the top heat to pre-heat, be sure to turn it off with time to cool down so its residual heat in the elements doesn't re-radiate downward on the bread. For instance, if it takes 20 minutes to pre-heat, turn off the top heating element 5 minutes after starting pre-heat.
Net: It's the top heating element (with 900 degree "radiant" heat) that is causing your new situation, and you need to figure out how to use it, or NOT use it, to get your desired result.
An important concept to understand for ovens with top heating elements is: _radiant_ heat (direct "shining" like the sun) versus "convection" or "air temp."
You air temp may be 450 - 500 F, but the radiant/shine heat of a heating element is 900 F and more, if it is directly exposed to the bread. This is like how the temperature you feel on your skin is higher in direct sunlight than in shade, or how a car gets hotter in sunlight than in shade.
I think these ideas are best illustrated here:
http://www.thefreshloaf.com/node/64854/deck-oven-problems-steam
and here: http://www.thefreshloaf.com/node/65316/new-oven-build-preliminary-results
as kendalm wrote "top heat kills bread."
Good luck, amigo. And bon appétit.
interesting note from DanTheBaker who uses a polin. I believe he preheats at 600f and dials down to 520 after loading. I’ve had a lot of good results from turning off my top heat prior to loading. So this surprises me!
Maybe try scoring deeper and more to the ends too? That will allow the loaf to open up and spread out more. The loaf in the photo looks like the score is short. but for sure top heat will restrict expansion.
in this case, i'm thinking _more_ top heat, which would ultimately lock the oven spring in place and restrict expansion like you've mentioned. is that right?
You do want your dough to expand, otherwise the crumb would be tight. top heat would restrict expansion not just vertically. you might even get a blow out to the side.
i would suggest one or more of these to try:
- score deeper and more to the edge
- increase hydration
- reduce or eliminate top heat
thank you!
Update:
After taking everyone's suggestions in, I ran a test of turning off the top heat for the first 15 minutes of the bake. It made a huge difference. For one, the bottoms of the loaves were no longer curling up. And two, the belly of the bread opened up more consistently during the first half of the bake (with steam)
See below for an a/b of the following:
Top heat: 480
Bottom heat: 465
85% hydration country sourdough
(A) was baked while keeping top heat on the entire time
(B) was baked with top heat OFF for the first 15 minutes (w/ steam), and then turning it back on for the second half of the bake.