Scaling cake recipes. Any magic?

[MarkIsCooking]

I'm appealing to the amazing wealth of baking knowledge here. I have several recipe for 9" 3 layer cakes. I want to be able to convert these recipes to 6", 12" and 1/2 sheet pan versions.

Words of wisdom? Tips? Resources?

Please help!!!!

[tino27]

Not to go all junior-high math or anything, but wouldn't a comparison of volumes of the different pans be a good starting off point to determining how much less or more batter you would need?

Volume (cylinder) = Pi x radius x radius x height

Volume (rectangle) = length x width x height

(Pi is assumed to be 3.14159, radius is diameter / 2)

Volume (6" pan, 2" height) = Pi x 3" x 3" x 2" = 18Pi = 56.5" cubed

Volume (9" pan, 2" height) = Pi x 4.5" x 4.5" x 2" = 40.5Pi = 127.2" cubed

Volume (12" pan, 2" height) = Pi x 6" x 6" x 2" = 72Pi = 226.2" cubed

Volume (1/2 sheet, 1" height) = 12" x 20" x 1" = 240" cubed

So to go from a 9" to a 1/2 sheet, you would need to double the amount of batter. To go from a 9" to a 6", you would need to use a little less than half the amount of batter.

Would it be as simple as this?

[Sugarella]

....Would it be as simple as this?

←

No.... you'd need to adjust some of the leavening and/or other ingredients in the recipe to get it to turn out like the original, and even then it won't always be right.

I never could make heads or tails of the formulas because the rules change based on ingredients, or can vary when using different brands of ingredients. I always found it easier to just make a second smaller cake with the leftover batter than trying to scale up or down the recipe, especially when dealing with any alkaline ingredients.

Sorry I know that's not the answer you're looking for.

[chefpeon]

As a pro, I have to scale cake recipes up and down all the time.

I'm nowhere near the math and science Tino offered up!

It doesn't have to be that complicated though.

I've also found that it really isn't necessary to adjust leavenings as Sugarella suggested.

I mix anywhere from 20 qt to 60 qt bowls of batter and I have to get several sized cakes

out of each batch. I can't be adding the leavenings separately to each cake....that would

take me forever. The suggestion of leavening adjustment comes from Rose Levy Beranbaum,

and honestly I can't see her reasoning behind this. I've successfully scaled cakes up and

down proportionately for 18 years with no leavening adjustment, and everything has been

just peachy.

My "professional" time-saving non scientific method of scaling is uber-simple.

Let's say you have a recipe, as you say, for a 9 inch 3 layer cake, and you just have a KitchenAid mixer. I'm assuming you're a home baker. Let me know if I'm wrong. I think you can successfully double it and it would still fit inside a 5 qt KA bowl. If you tripled it, maybe not. It depends on the size of your mixer and how much batter the recipe is allowing for each layer.

So, if it were me, and I wanted to make a 12 inch cake, I'd double the recipe proportionately,

and fill each 12 inch pan just a little over halfway. Chances are you won't get three separate layers out of this and you'll have to mix up another batch. Any leftover batter gets made into cupcakes.

By proportionate doubling I mean this:

Original recipe:

2 cups flour

Doubled recipe:

4 cups flour

Can't get much easier than that. Works too.

[dougal]

Any suggestions about how baking time (or temperature) might vary with different sized tins?

Or is it near enough the same with the same batter depth, whatever the tin size?

Edited August 20, 2008 by dougal (log)

[jumanggy]

With respect to cakes without chemical leavening, it is really simple.

For example, with the honey castella I just made, the recipe was for a 9x13" cake. I didn't have that pan, so I used an 8" pan instead. Assuming I was going for a cake of the same height:

factor = (3.14)(4)²/(9)(13) = 0.42

With all the measurements in metric, it's easy to multiply them all by 0.42. With respect to the eggs:

7 whole eggs, 3 egg yolks = 7 egg whites, 10 egg yolks

x 0.42 = 2.94 egg whites, 4.2 egg yolks = 3 whole eggs, 1 egg yolk

Not a drop of the batter was wasted, no overflow either. Regarding the the baking time, it's a little more complicated, but if you have a feel for how a cake behaves while it's baking, you can watch it every 5 minutes after you *think* it should be done and write the figure down for future reference.

The original 9x13 cake bakes for 1 hour, the 8" round cake at the same height baked for 35 minutes. I'm sure the factor is very different for different kinds of cake. Thinking about it, a cake of the same height but different width and length should bake at the same time because the heat of the oven penetrates the surface equally at all points, but I dunno why it didn't work that way for my cake.

If a cake has chemical leavening, it confuses things a little bit but I'd suggest checking out other cakes of the same (new) size with similar methods and trying out the prescribed leavening amount there. I scaled down a carrot cake that called for an 8" round pan, 4" height to a 6" round pan, 2.5" height, but didn't scale the baking powder and baking soda by the same factor as the rest of the ingredients (1/5 teaspoon soda and 1/3 teaspoon powder? uhhh... no). I just threw in a scant half-teaspoon of each. The cake managed to reach 2" of the 2.5" (I don't know if the original cake would have reached 4" anyway), but I was very happy with the result.

Er, good luck!

[Tri2Cook]

I'm not a pro but I'm going to have to go with Annie on this one. I never adjust the leavening for the pan. I tried the RLB formulas and was happy with the results... but I've been just as happy without doing it. For a one-off cake it may be worth playing with but for baking lots of cakes on a regular basis it's just one more thing to do that doesn't seem (to me) to make enough difference to be worth it. There probably is a sound reason for doing it but the difference is for people well above what I do to recognize because I just don't see the difference in the end product. I mix my batter and put it in the pans I need it in regardless of size, I don't adjust the temp, I do adjust the time. Keeps it nice and simple which is good for me because cakes are not my favorite thing to do. I only do them because people want them.

[onehsancare]

I would generally call myself a faithful disciple of RLB, but I note that Annie and Sugarella's system essentially debunks the "need to adjust leavening" theory.

I double recipes, fill the pans I want appropriately, and make cupcakes or smaller cakes out of the rest of the batter.

[Pam R]

Just wanted to join the chorus - I never adjust the leavening when I do larger batches (2X batch gets 2X leavening).

But baking time, yes, I adjust that. Having said that, I don't think I've ever baked something for the exact time called for in a recipe. My 350 oven isn't the recipe writer's 350 oven. So if you're baking in a smaller pan, start checking it earlier.

[chefpeon]

Yes, baking time and (sometimes temp) are different if you are baking a smaller or larger cake than the recipe is written for.

Obviously smaller cakes and especially cupcakes take much less time. Larger cakes take much more time. If you have a recipe that's written for a 9 inch cake and you've scaled it up to make something like a half sheet, then it will bake longer, but you also want to turn the oven down a bit for really large cakes, like half sheets, quarter sheets, 12 inch rounds on up. If the oven temp for a 9 inch cake states for you to bake it at 375, go for 350 for the larger cakes; otherwise the outer edges of the larger cakes will dry out too much before the center is baked. Too high an oven temp can also lead to too much doming in larger cakes.

[pastrygirl]

It shouldn't be too hard to find a list of what volume the most commonly used pans hold, I think the Cake Bible has one somewhere in back, or the Food Lovers Companion. This would be in cups instead of the cubic inches that Tino calculated, but it would be helpful in deciding which pans will equal which other pans.

Or a quick google: http://www.joyofbaking.com/PanSizes.html

[sugarseattle]

i agree on the whole "no need to adjust the leavening". if you are scaling the recipe by weight, there is very little margin for error. however, i try to adjust in stages until i feel comfy with the results...for example do 2x first, then 4x, then do a big jump like 16x.

probably the whole "need to adjust the leavening" comes from eggs, which can vary a lot in weight egg to egg. if you're scaling them, it's much more accurate and you don't need to adjust when multiplying up or down.

[Lisa Shock]

I don't adjust the leavening either.

However, I make certain to use recipes that are written by weight, not by volume, since the errors made by 'measuring' by volume can be magnified when making a large cake. I won't repeat theKitchen Scale Manifesto, I'm just mentioning my agreement with it.

[gfron1]

I am a professional (I'm just not sure in what yet), and I'll disagree in my certain context. I'll also not offer any fancy formulas because I have more disasters than successes! That is why, my friends, you are highly unlikely to see me make a cake and post it in these forums

At altitude, it seems that scaling leavening is important. Now, I'm not talking about the altitude leavening adjustment that we know has to be done (as much as 50% less - thank you pastrygirl for the tip), but when I do varying sized pans as suggested in this example, if I use the same batch of batter, each cake will have a different outcome. Think of it (and this is a terrible analogy) as a battery of cannons - each cannon of a different size. The short, stout cannon shoots a heck of a cannonball, but it doesn't go very far. The tall, thin cannon shoots a smaller ball, but a very long distance. So...if you're still with me on this analogy, if I put the same exact batter in a 9" pan and an 11" pan, and fill them to the same level, inevitably my 9" pan will do fine, and my 11" pan will rise and crash.

Okay, like I said, its not a perfect analogy (maybe volcano spouts would be a better one - this has to do with constriction and pressure I think), but I wanted to give the physicists something to work with

[lilthorner]

I make a cake from the cake bible quite often. the sour cream butter cake.. the only time I make it the same amount as in the book is if I need a dozen cupcakes.. I double it for 2 9 inchers, triple it and I have 4x it for my kitchenaid 5q mixer.. I have 3x and 4x written in the book next to the original, and I have it written that 4.5x fits in a 12x18. I never adjust the leavening in the recipe, it calls for soda and powder.. I read the formula before but unfortunately it was right when I needed to be baking LOL so I scrapped that math and just doubled..

[chefpeon]

gfron, I think you're right.....when you're at altitude, the air pressure is so much less that differences in leavening vs. size of the cake probably DO make all the difference. I can totally see what you're talking about, and that's a good thing to keep in mind for people who ARE at altitude!

We who are at sea level have enough air pressure that differences in leavening vs. size of cake makes no discernible difference. I'm glad you brought up the altitude issue, because certainly, not all of us live at sea level!!!!