baking time versus number of items in oven
I doubled a recipe for apple cake, and filled two 13x9 pans. Into the 350F wall oven they went. Recipe estimates 50-60 minutes.
60 minutes later, probe comes out pretty damp, and cakes are more than a bit jiggly. Easy enough, bake a little longer.
What's going on here? Do two room temperature cakes depress the initial temperature for a lot longer than one?
p.s. Oven calibration recently checked, so it's not that.
I was baking these cakes one atop the other, with a few inches between, in an electric oven. I did not have convection turned on.
Best Answer
(1) Are you baking them upper/lower or side-by-side?, (2) Is your oven's outside width 24" or 30"?, & (3) Gas or electric?
My guess would be that either you have a 24" oven and you're baking upper/lower or you have a 30" oven and you're baking side-by-side. Either way, I think the ultimate culprit is heat circulation - certainly you wouldn't be having this problem in a convection oven, right?
If you're baking them upper/lower in a small oven, I believe that heat absorption would probably create areas of lower temperature above both pans that wouldn't even out well without convection. If you're baking side-by-side in a larger oven, I believe that the total area of your pans would create a heat block and a temperature differential between the top and bottom of your oven that would not dissipate well without convection. And while I think the circulation problem would be less of a problem with gas, I'm pretty sure it's going to present a problem in either type of oven you use.
Being the owner of a 24" electric oven myself (so the interior of my oven is 18" x 18", not including the ribs that support the racks), I can't even bake two 9" circular cake layers at the same time (either diagonally or upper and lower) without grotesque deformations in the tops of my cakes. And two 9" round pans with a thin layer of cake batter are going to be less of a heat magnet and obstruction than a thick layer of apple cake batter in two 9" x 13" pans.
Ultimately I think the problem is not one of time but of maintaining temperatures above and below your pans - and adding time to the bake won't resolve the problems caused by such a differential. Alas, I believe that your best option is to give each cake its own space and time in the oven. Whether it's a heat conduction issue or a circulation issue or some combination of both, I think the variables involved are WAY too complicated to ever lead to a general baking time extension guideline when doubling-up a recipe.
Bake them separately - and, yes, I realize that's not a very satisfying recommendation.
Pictures about "baking time versus number of items in oven"
Does it take longer to cook multiple things in the oven?
The dishes will typically take 15 percent longer to cook than if only one is cooking, so adjust the time accordingly. To ensure even cooking, make sure the oven is fully preheated before inserting dishes, and rotate the dishes halfway through.Does the amount of food in an oven affect cooking time?
The size and the amount of "work" the oven needs to do is the exact same on each item individually ". It's true that the oven has to deliver the same amount of energy to each item. So in total it has to deliver twice as much. It only has a finite amount of power available and so it takes longer.When you double a recipe what happens to the baking time?
6. Cooking and baking time will be different. When you double a batch of cookies it doesn't take double the time to bake them, it just makes more of them. Doubling a cake will make it take longer to bake, but it won't double the time.Do you increase baking time for two cakes?
Move the cakes twice during cooking so that each cake spends an equal amount of time in each position. TOP = PALE Cakes stacked above each other disrupt heat flow in the oven. SIDE BY SIDE = EVEN Cakes kept side by side bake up evenly.How to BAKE using an Electric Oven.//*Basics*
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Answer 2
Yes, two cakes will take longer than one, but only by a tiny bit. The second cake is an additional heat sink, but it shouldn't be enough that you'd notice it if they're on the same shelf. Did you open the oven to switch the places of the two cakes? If not, you should have, and that would definitely increase the cook time. If the two are on different shelves, one would block some heat from the other.
Answer 3
Do not put one cake on top of other..Always, if you have to put side by side with inches between or one to left and one to right on diffrent racks but never over each other..
Answer 4
You should never cook 2 cakes same oven, same time=problem! Easy fix, cook seperately!
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