Why do Cakes Collapse??

Well a cake is two things; its has an infrastructure of starch (from flour) reinforced with egg proteins, and filled with fats and sugars and the most important; air.

The simple answer as to why cakes collapse is the network of proteins and starches are not strong enough to hold the expansion of air.

This could be because of your recipe; too much sugar and fat to egg and flour, or it could be your aeration method; if your creaming the sugar and butter, they will pick up a significant amount of air, as will the eggs (if beaten or whipped), as will the mixing method, so a chemical leavening (such as baking powder) may not be neccassary, or may not need much, perhaps you're adding to much.

Or maybe your cooking temperature is too low; too much air is generated by the leavening before the starches gelate and the proteins combine (therefore forming its structure) and it can't hold it- therefore the cake swells but does not trap the air.
A good cooking temperature is between 175-190 deg C, it may be worth getting an oven thermometer, just to make sure your oven isn't lying to you.

Something else less obvious to think about is perhaps your cake tin is reducing the internal temperature of the cake: Shiny metals WILL reduce the temperature of the cake (signficantly) as the radiant heat from the oven is reflected. A cake cooked in a glass or dark tin will cook 20% faster than one in a shiny tin.
So if your tin is shiny you will need to increase the baking temp.

One last thing; allow a small resting period before you remove from your cake tin- as the proteins and starches are still very unstable when hot.

Sorry to not give you a clear answer; but as you said there are many reasons why your cake could be collapsing.

Chef Lawrence is essentially correct, if your recipe uses little flour then there is nothing else in there that will support your network of air bubbles. Some cake recipes, like souffles are simply destined to collapse eventually.

Another reason is the size of the cake tin. If you happen not to have the right size, it might be too narrow and make the cake too heavy, or too wide and the structure is not able to span a wide enough space (think of a large dome in architecture).
Many people think the size of the pan is just indicative, but actually it's very important.
Another possibility is counter-intuitive. Apparently too much leavening (baking powder, baking soda) can make the cake collapse because it is too high a dome and the structure of that cake can't sustain it.
Finally, if your almond cake ALWAYS collapses, maybe it;s not a great recipe. Many people publish recipes and make mistakes in copying down quantities, or there are typos, or sometimes they just don;t measure but then put in approximations of their eyeball measures.
It seems to me that adding almond paste would necessarily make for a very heavy batter, very hard to keep aloft!

Very interesting point. I never knew that, thanks for sharing it.

I once gave a recipe for a cake to a guy here (where recipes are always approximate and nobody ever explains anything) and he laughed at the precision with which i described every step. In particular he thought i was exaggerating when i gave the precise cake pan sizes. I said look, it;s important, it won;t come out in a different sized pan.

A couple of weeks later i talked to him and he said "ah, your recipe wasn't very good, it didn;t come out". I asked about the various points of the method, the creaming, the measurements, the folding,. etc. Then i said, hey, did you use the right sized pan?
He said, oh, no, i didn;t have that size.
I nearly screamed - I TOLD you it was important, and you didn;t even bother to point out that you didn;t use the right size? Of course it came out dry and flat, the pan was too large!

I wanted to add a bit re chemical leaveners...
As mentioned, because your recipe is using only a small amount of flour, as well as almond paste and eggs, then I'm assuming the eggs are giving the majority of the volume and stability (the paste is probably weighing the batter down a bit). There are different types of chemical leaveners, and each effect cakes in very different ways. To make it concise:

Baking Soda
-Single acting (does not require heat to start working)
i. Because it is single acting, it starts to react immediately. Thus, if you don't put your batter into the oven right away, all the gas (C02) created by the Baking Soda will escape
Baking Powder
-Avail Single or Double Acting (ie, reacts immediately, or requires both moisture and heat to fully react)
Baking Ammonia
-reacts very quickly, creating lightness, however, gasses may escape quickly if not baked immediately.

The reason why an excess of leaveners will collapse a cake, is because the gluten strands (Gluten = protein from flour that creats strands that gelatinize and become part of the product's structure) can only stretch so far and if you have too great a reaction at too short of a time, the strands will break and the cake will "collapse".

Now, as far as the eggs go, because of the protein content of the eggs, the emulsifying properties of the yolk, and the volumizing properties of the whites, if they are whipped/beaten and then folded into your batter, they are creating the structure for your cake (since there isnt much flour). If you think your cakes are collapsing because the eggs aren't stable enough, and if you are using egg whites, I would suggest adding a small amount of acid (cream of tartar, lemon juice,vinegar, etc) as that will help help stabilize and maintain the volume in the whites until they are baked/coagulated.

Another thing you could try is to decrease your butter just a tad bit. Although the fat helps with the overall mouthfeel and texture of the cake, it also shortens the gluten strands from your flour, and even though they are supported by the egg yolk, it could be that there is just too much fat for them to stabilize and 'set'.

'neway, I hope you're able to solve your collapsing problem, and if you do figure out what the cause is, please tell us ^^ Also, I hope everyones explanations will shed some light on the science behind baking...before I knew about coagulation/geltinization, and the roles of fats, eggs, leaveners, flours, etc in baking, I had no clue as to why things were happening! ^.^ hope you figure it out!

-moet

oh hey! have you tried doing your own AP mix and using 50/50 or even 60/40 (bread/cake) to increase the protein content? Or maybe even subbing pastry flour instead of cake flour?

It's always nice to have the recipe before diagnosing baking problems; and nice to have a complete description of the problems as well. In this post, despite generations of ancestors wishing you to remain cae canny, you may just have given enough information.

Your cake doesn't just collapse, it over-rises, then collapses, then sinks. The problem is not so much the collapse in the middle, but the early luft and final sink-hole. Your cake has very little structure, because it uses very little flour. So, the way to control the rise and fall of dessert is in the mixing, baking and cooling stages. (What else is there?)

Okay, you've figured out that you're not supposed to overbeat after adding the flour. Well, don't overmix before either. You're creating air bubbles, and when the cake bakes, the air in the bubbles heats up, causing the bubbles to swell. When the cake cools down, the air shrinks; but there's not enough structure in the cake to support the swelling -- so it, as you say, collapses.


Don't use too hot a oven. Lower your temperature and bake longer -- you may even want to use a "bain-marie," as though baking a cheesecake. It will be similarly helpful to prevent the cake from cooling too fast. In fact, think of your cake as being like a sort of flan or custard rather than an actual cake -- just like a cheesecake. Which means:

• Don't overbeat during any part of the process.
• Use a moderate oven (about 300 or maybe even a little less).
• Use a bain-marie.
• Finally, allow the cake to cool in the oven -- first with the oven off and the door slightly open, then with the door open and the rack slid partly out (vestibule cooling) -- before putting it on a rack.

Hope this helps,
BDL

PS. Let us know what you try and how it works out.

Does it mention a mixing speed(eg. mixer on high or by hand)? If the intention is for high speed and that is not mentioned in the recipe, that could be causing the collapse. Force, from mixer speed, can aid in gluten production, if I recall correctly.

I'm sorry BDL i know you're a very experienced chef, and your insights are extremely enlightning but I must disagree with what you said here... A cake is not a cheesecake, a cheesecake is in fact a dense custard, the slower the proteins in the eggs combine, the more delicate the texture. If you bake a cake (with leavening) with the same method, heat will react with the leavening (most efficiently at 60degC) but the eggs will not begin to coagulate until 78-80degC and the starches will not Gelate until around 100deg.
What that means is the lower the temp, the more air is produced will a lack of structure to hold it.

Keep your heat high I say.

I have a recipe for cheesecake, that requires no eggs, therefore it cannot be a custard.

Quite right, however if it is a baked cheesecake using eggs to set; its a custard.

I should of been more specific with my finite statements.

well the idea of a cheesecake to lose the air (we don't want to stir too much because we don't want to integrate too much air into the mix) as this will cause rising and collapsing the idea of cakes is to trap the air. Its two opposites. So unless you want a very dense airless cake (which you may do) its important you do everything you can to suuport the structure of the cake to trap the air.

You're right that the proteins of the flour are not giving the cake its structure, but there are two structural qualities to flour; proteins and starches, in cakes we want to encourage the starches but discourage the proteins. The starches gelate at around 100degC, which means they swell with water and bind to amylose proteins in the eggs, the fats, sugars and air. The trick is to get it to the temp as quick as possible without burning the outside of the cake.

I would reccommend a series of experiments to work out exactly what the problem is; get an oven thermometer to make sure you know the exact temp and bake between 175-190deg C (depending on how shiney your cake tin is). Cool slowly (i would remove from the oven but not from the tin for 20-30 minutes) and then rack it.

If your cake is collapsing then your recipe is based off a different set of ingredients (perhaps flour) and you may need to add a little more flour for stucture. (I would add flour before adding extra eggs. As the gelated starch is more important here.)

And see how it goes: all I can say is don't be afraid to break the mould of your recipe, and experiment a little; but try and be precise with your measurements so you can reproduce them in the future. Good luck!