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Author Topic: why do cakes rise in the middle?  (Read 7968 times)

paul.fr

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why do cakes rise in the middle?
« on: 08/06/2007 10:38:11 »
when baking cakes i notice that they all rise in the middle. why is this, why not rise at the sides or in equal measures?


 

Offline Ashtari

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why do cakes rise in the middle?
« Reply #1 on: 08/06/2007 14:23:46 »
Could it be that the oven is more hot in the centre where the cakeusually is???   [:o)]
 

Offline kdlynn

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why do cakes rise in the middle?
« Reply #2 on: 08/06/2007 16:01:22 »
i don't think so. things usually burn around the edges first, not the middle... i mean... not that i've burnt anything... or anything
 

Offline daveshorts

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why do cakes rise in the middle?
« Reply #3 on: 08/06/2007 19:54:55 »
Could it be because it cooks from the outside in, so the outside cooks and goes hard before it has time to rise all the way, but the centre has more time to rise so it produces more CO2 and therefore rises higher.
 

Offline Soul Surfer

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why do cakes rise in the middle?
« Reply #4 on: 09/06/2007 10:45:29 »
Yorkshire puddings in large trays tend to rise at the sides and fruit cakes can sink in the middle if you get them wrong 

It is an interesting problem and is a function of the temeperature and viscosity of the cake mixture and the rate of cooking.

It takes an expert chef with good knowledge of the equipment they are using to get it exactly the way they want it.
 

Offline eric l

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why do cakes rise in the middle?
« Reply #5 on: 10/06/2007 18:40:20 »
My first thought was that it must be due to the mold.  Before the cake goes in the oven, fermentation has started and carbondioxide is formed.  As the cake goes in the oven, temperature rises and the gasses inside the dough expand.  But the mold with its solid walls prevents the gasses from expanding that way, and forces them towards the middle (and upwards, too, but there you have the formation of the crust to limit the expansion).  Anyway, because the gases can not expand sideways, they are pushed towards the middle, where you end up having more gas, so more rising.
On the other hand, if you take a traditional loaf of bread that is baked without a mold, it will come out higher in the middle, too.  But that could be because you start with more dough in the middle as you put the loaf in the oven.  Turkish breads are pretty flat as they go in the oven, and they come out pretty flat too.
 

Offline rosy

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why do cakes rise in the middle?
« Reply #6 on: 10/06/2007 19:17:29 »
At the point at which rising occurs, the cake batter is quite sticky and is probably inclined to adhere to the sides of the tin, so more force is needed to push upwards? The peeling-away-from-the-sides characteristic of a nicely cooked cake is (I think) something that happens later in the cooking process.
 

Offline Karen W.

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why do cakes rise in the middle?
« Reply #7 on: 10/06/2007 19:33:06 »
Interesting question and answers too!
 

Offline elegantlywasted

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why do cakes rise in the middle?
« Reply #8 on: 11/06/2007 05:01:08 »
I think rosy is the closest. The leavening agent used in the recipe causes the cake to expand. Because the cake is in a baking tin, and its a cake, there isn't enough force from the expanding cake to move outwards (edges of the pan) or downwards. Therefore the cake can only expand inwards and upwards, hence the rising in the middle :)
 

Offline rosalind dna

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why do cakes rise in the middle?
« Reply #9 on: 20/12/2007 12:25:07 »
I think that the cake rises in the middle when you bake it, is because you have
beaten it well and the air helps it to rise faster as the air bubbles go to
the centre of the cake.

It works for most cakes. Although if does depend on the type of cake that you are making, sponges will rise faster as the mixture is lighter in my experience than fruit cakes.




 

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why do cakes rise in the middle?
« Reply #9 on: 20/12/2007 12:25:07 »

 

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