The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Oven spring: two types in one go?

Yumarama's picture
Yumarama

Oven spring: two types in one go?

Here's a question I'd like to pose to all of you experts:

In the attached pic, you'll see that the two loaves on the left have a - what I'd call - "tight" crust; the slashes didn't open up so much, while the two on the right  have slashes that expanded considerably more, in spite of my small mistake of not making the slashes close together enough. Oven and stones were pre-heated for 40 min.. The two loaves on the right went onto the stones on the bottom rack of the oven first, then the two on the left were at the top.

Two different oven springs, same bake, same dough, same weights...
(Click to see bigger version)

Once all bread was in (and it was a fast-as-could-happen open oven, toss in, close oven, get next loaf) then the steam was added - I already had a pot with about a half inch (1 cup) of boiled water in the bottom but also threw in about a quarter cup of water onto the bottom of the oven for instant steam. The loaves were switched top to bottom at about the 20 minute mark. If there's more detail someone needs about a step to help figure this out, please ask.

What's not visible from the pic: the bottoms of the left loaves are decidedly more cooked, edging on too dark (with a slightly bitter burnt taste) while the right loaves can be seen as a little darker overall but the bottoms weren't overdone at all. Which really baffles me since the non-overdone bottom loaves were right over the oven element while the top loaves were further away, yet charred a bit a but stayed lighter. It's like a contradiction, seemingly illogical.

So the question is: what made the right side loaves on the bottom expand more than the ones on the top? Hotter top? Hotter bottom? More steam at the bottom (near the water pot)? Whatever worked on the bottom, I'd obviously like to try and make it happen to the top loaves as well and if that means switching loaves over a lot earlier, then so be it. But what is it the bottom loaves got that the top ones did not?

(I might have added this question to my other thread but I figured this could be of use to others so I gave it it's own thread.) 

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Paul

Mini Oven's picture
Mini Oven

I misread the first time.  Got my left and rights mixed up.  It happens.... :) (If any of you read my first answer, just forget it.)

The top loaves got steamed first (hot stuff that steam) and being hotter at the top were done first.  (Did you turn the heat down after 20 min?)   I think your upper coils heat longer and hotter than the lower coils.  Try switching the stones before the dough goes in.  Then if the upper stone is hotter, it will be on the bottom.   

Or, (light bulb goes on...!!!!) Maybe your coils got switched around when the oven was made and the upper coil should be on the bottom and the bottom coil on top.  Can you reverse them easy enough?

Mini

Yumarama's picture
Yumarama

I guess different ovens would fire up different ways. In my case though, the upper coil only comes on during the initial heat-up which is basically the first 10 minutes or so of the pre-heat. After that. it's just the bottom coils maintaining the already high temp steady. Since I pre-heat for a good 30-40 minutes (so the stones get hot) that leaves about 20-30 minutes where the bottom stones are exposed to the bottom hot coil long after the top coil has stopped coming on. So I'd assume if either stone were to be "too hot" it would be the bottom ones.

Switching the stones around isn't really feasible as it's not one big stone, it's a bunch of small ones so doing that would mean way too much time with the door open, losing all the heat that's been built up. 

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Paul

MommaT's picture
MommaT

How long did you heat your oven for before putting the loaves in? If it wasn't a long enough time it may be that the bottom stone as appreciably hotter.  This could have created the 'spring' in the loaves that started there and overcooked the ones that ended there.

Just a thought... 

 

MommaT, Novice Baker 

kanin's picture
kanin

I think I understand what's happening with your oven. My oven fires up the same way.

Clearly the bottom stone and ceiling of the oven has more heat. With that in mind...

For the left loaves:
You finished them off in the bottom stone, which is hotter. When they got transferred there, they will lose moisture and caramelize at a quickening rate because they were halfway done at that point. The right loaf bottoms did not burn because they considerably had more moisture during their stay there, which was at the beginning of baking.

For the right loaves:
They had more oven spring because they started in the bottom of the oven where there will be more heat. It's closer to the steam source so that probably contributed as well.

The tops on the right loaves were more browned because you finished them off on top of the oven. It's the same reason why the left loaves had bottoms that were too brown.

 

I hope I'm making sense :)

 

http://www.applepiepatispate.com

KosherBaker's picture
KosherBaker

Hi Paul.

I think you have discovered the reason why bread is always baked in the lower two thirds section of the oven. :) Not on the very bottom though.
As you may know heated air is lighter than ambient air and therefore rises to the top. So both the Air and the Stone on your upper shelf were hotter, much much hotter. In fact they were so hot that they had set the crust on the bread before it had a chance to fully rise. When this happens the bread either develops a crack, or it bows. If you look at all four of your loaves they are all bowed. And since the temperature at the top was so much higher, the bottoms of the top loaves burned since they lost their moisture sooner. In my experience bowing (or bending) of the loaf happens for two reasons. 1. Exposing a loaf to too high a temperature for too long. 2. Not enough steam in the oven for the first 25% of baking time. Or both. :)

If I were to take a guess, and it would be just that a guess. I would say these guys were steam starved. It looks like you have an electric oven which runs much dryer than a gas oven, as gas generates some steam when it burns off. So perhaps a discussion on steaming strategies for electric ovens is in order. :)

Of course if you always bake your bread at 350F, the amount of steam present may not be as big an issue. But once you start getting the temperatures up higher
it becomes more critical.

HTH, Rudy 

Yumarama's picture
Yumarama

Heh... Well, that's a dozen possible reasons, all of which are likely to be right or at least influencial on the issue. Much to ponder...

Thank you everyone!! 

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Paul

Mini Oven's picture
Mini Oven

so try rotating loaves after the first 12 minutes.   See if you can find a flat, narrow pan to park on the bottom of the oven at one end (left or right, this might create some circulating currents of steam in the oven.  Pour boiling water into it before closing the door, if you can, I have a long handled turkish coffee pot that works well to pour hot water.  However my favorite steaming method is to take an iron pan that has been heated on the stove with 1 cup boiling water already in it and shove it onto the oven floor and remove it when I rotate the loaf at 12 minutes.  That and the "Magic bowl." 

How much circulation room is between stones and oven walls?  I thought stones take about an hour to heat up.    I don't use stones because of the long preheat time but you've got more bread to bake than I do.  Is there a handy way you can leave spaces between the stones when they preheat and push them together again before adding loaves?  Or better yet, can you space the stones so there are spaces between the loaves for circulation?  That would be placing the stones for the smallest amount of exposed surface area.  The loaves would look like they are floating in the oven.  Alternate the pattern on the top shelf.  Reduce the heat.

Paul, do you have a fan in your oven?  I know, a hundred questions.... what does your oven manual say about baking bread?   When I use the fan combined with lower heat, my vents close and it turns into a steaming chamber if hot water sits on the bottom, cute huh?  It's an Amana oven. 

Mini O

Yumarama's picture
Yumarama

Woah, OK, let's see...

Mini wrote:
See if you can find a flat, narrow pan to park on the bottom of the oven...

The bottom of the oven is taken up by the electric element, it's exposed and above the floor so there's no real way to put a pan of any sort there except a small pot I can tuck into a bend in the element in the center front. Which is what I've been doing.

Quote:
That and the "Magic bowl."

I assume this is the "cover the bread and let it steam itself" trick? I'll need to hunt up a proper-sized metal cover to do that.

Quote:
How much circulation room is between stones and oven walls?

There's a good 6 or 7 cm of airspace around all sides of the stones.

Quote:
I thought stones take about an hour to heat up.

I dunno... do they? It's not that thick, a hair under 1cm?

Quote:
I don't use stones because of the long preheat time but you've got more bread to bake than I do.

Actually, I don't; I made four loaves last time and the last one was starting to get a bit dry so I'll keep it to 2 from here on unless I'm gonna give it away. This will solve a number of issues like which loaves go above. I was thinking of trying the cold-oven technique with a plain metal tray but then I still don't want to throw too many variables into the mix yet.

Quote:
Is there a handy way you can leave spaces between the stones when they preheat and push them together again before adding loaves? Or better yet, can you space the stones so there are spaces between the loaves for circulation?

Not too feasible. I did accidently make a gap in the stones when I was putting in the first loaf last time and the dough immediately started to "melt" down through the gap. Again, spending time moving the stones around lets a major amount of heat out of the oven.

Quote:
Reduce the heat.

OK, now you're just making fun ( :( sniff). It's not like we even know what the temperarture really is. No, I have not yet found a trustworthy thermometer. Well, none I wouldn't have to order from the US and pay freakish shipping costs. So I keep hunting but it's like they don't exist around here. It's either the cheapy coil ones or... well, there is no "or", it's only cheapy coil ones.

Quote:
Paul, do you have a fan in your oven? what does your oven manual say about baking bread?

Nope. Just a plain ol' cheapie GE. Well, not all that cheap actually, I was rooting through old receipts for our Bosch clothes washer that went on the fritz this weekend and found the bill for the stove, $600 nine years ago. Not high end by any means but not entirely low end either. Still, nothing exciting oven wise.

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Paul

Mini Oven's picture
Mini Oven

for answering my Q's.  If you can see your coils, does that mean you can see your thermostat?  Where is it and how is it held to the wall?  

To comfort you... even if you don't know the temp of the oven, turn it down just a little bit from where is has been set.   I'm not making fun, it is indeed a balancing act to get the right temp.  Rudy has some good points mentioned above.

Try baking on non shiny pans, preferably dark bottom outside underneath,  use the rack and no stones (gosh they are thin, I thought they were close to 2cm thick.)  Preheat (because you have a large oven) for 30 min only and place the baking rack about 2 inches or 5 cm below exact middle of the oven.  Chances are you did all this already and that is why you are using tiles or stones.  If so, then all you need to do is tun the oven down just a wee bit. :)

The steam pan on the bottom next to the coils is not making it, not hot enough.  How about the second rack placed just above the coils and a dark shallow narrow metal pan placed at one side next to the wall right over a coil?  (the loaves above could be shoved a little more away from the pan for although it provides steam it absorbs heat away from the loaves.)

You could heat up this pan on the stove with a cup of boiling water and place into the oven when loading the loaves.  (I don't like getting blasted with steam when water is added to a hot pan in the oven, it steams up my eye glasses and not sure how safe it is, too easy to want to slam the door shut.)  Or you could place in the preheated shallow pan a tin can with a hole near the bottom and as the water runs out, turns to steam as it hits the hot pan.   You just hold a finger over the hole until it is in place.   A little trial and error would help decide the placement and size of the hole and quantity of water.

I'm in the process of darkening my ss magic bowl, it reflects too much.  I smear it with oil and "smoke" it brown as I bake.  Looks really "used" now. 

Mini O