The Science of Cake Bakery . . .

(A Simple Butter Cake)

From time to time readers ask me why their cake sank in

the middle when baking. They always say something along the lines of: "I

followed the recipe perfectly, but it still sank. What did I do?!"

While it's impossible for me to know exactly what happened in any

specific occasion without my actually being there, and I can't pretend to be an expert baker myself, these are the top 5 things you should look out for which may help to

keep your cake from sinking the next time you bake:

1. Old Baking Powder:

Baking powder may only account for a tiny percentage of your entire cake

ingredients, but it can ruin the whole thing if you're not careful!

Remember that baking powder only stays fresh for about 6 months to a

year, so date them when you buy them, and toss and replace any

containers that have been hanging around too long.

Not sure if yours is still good? Take 5 seconds to test it before you

start baking by placing a teaspoon of baking powder in about a 1/2 cup

of hot water. If still good, it should start to bubble rapidly. If

nothing (or barely nothing) happens, it's time to head to the store.

2. Too Much Leavening: As counter-intuitive as it might sound, adding too much

baking powder, baking soda, or yeast to a cake will cause it to sink as

the amount of air that is created within the cake will be more than the

structure can support and the whole thing will come crashing down.

Never add additional baking powder or other leaveners to self-raising

flour or cake mixes (they already have it mixed in), and always be sure

to read a recipe clearly and measure carefully.

When in doubt, remember that the average ratio for baking powder to

flour is 1 to 1.5 teaspoons per cup of AP flour; so if you read a recipe

that calls for something way above that, it's probably an error.

3. Overbeating: this is probably one of the most common reasons why cakes sink. I'm

not sure what it is, but we all seem to have a natural tendency towards

overbeating cake batter until it is smooth and creamy. This is even

easier to do when we rely on the trusty old Kitchen Aid or food

processor to do our mixing for us. But beating in too much air into the

batter once the dry and wet ingredients are combined will only cause the

batter sink.

Go ahead and work the air in when creaming the butter, sugar, and eggs,

but as soon as you add the flour mixture, remember that it's ALL about

the light hand. Fold the dry ingredients through the wet only until they

are just combined, then delicately divide and pour into your cake pans.

If adding anything at the end (food coloring, chocolate chips, nuts,

etc.), continue to work the addition through the batter as gently as

possible in a flowing folding motion.



4. Oven Temperature:

an oven that isn't properly calibrated and runs either too hot or too

cold, could easily make for a falling cake. If possible, spring for an

external oven thermometer (you can find them in the $15-$30 range at

stores like Bed, Bath, and Beyond) to make sure that when it says 350 on

the dial, it's really 350 inside the oven.

Also, don't be tempted to peek inside that oven for at least the first

80% of the suggested baking time. Remember that each time you open the

oven door, the temperature inside can drop as many as 10 degrees. These

tiny fluctuations in temperature can affect the even rising of the

cake.

5. Timing: Unless a

recipe specifically calls for it, don't let a finished batter sit for

very long before baking. 20-25 minutes while the first batch bakes is

fine; a few hours while you run out to pick up the kids and finish some

errands is not. I always strive to have my cakes in the oven as soon as I have finished mixing them, unless of course I have been otherwise instructed in a recipe.

Remember that the minute the wet and dry ingredients meet, a chemical

reaction starts to take place (like those baking soda volcanoes we all

made in 7th grade science class). To get a light, fluffy, and

beautifully raised cake, you want that chemical reaction to take place

inside the oven as the cake bakes so that the air that is created gets

sealed into the baking cake. If your batter is sitting on the counter or

on the fridge, the air created inside will just escape into the room,

and come time for baking, there will be less to lift the cake up.

(Irish Apple Cake)

And... a few bonus tips!

Preheating IS important. Depending on your oven, it can take as

long as 30 minutes for it to reach the optimal baking temperature.

Always be sure to do that first before getting on with your recipe or

you'll end up with an uneven, lumpy cake.

Baking Powder and Baking Soda are NOT interchangeable. Though

baking powder contains baking soda, it also has other components that

act as a catalyst for all that good air-creating cake-rising action, and

is used in recipes that don't have acidic elements. Baking soda usually

works along with an acid (lemon juice, buttermilk, yogurt, chocolate,

etc.). Some recipes call for both, but that doesn't mean that you can

skip one or the other; if it calls for both, be sure to use both.

(A Lemon and Pistachio Cake)

Center your oven rack. Unless otherwise told, position your oven

rack in the center and place the cake pans right in the middle of the

rack. If baking two cake layers at once, place them on the same rack

side-by-side; don't put one on top of the other; they won't bake evenly

that way.

As much as possible have all your ingredients at room temperature. I know it is very tempting to want to be in a rush and to think that it can't possibly hurt if all of your ingredients are at different temps. When it comes to the science of baking however, this variance in temperature between ingredients can make a really big difference when it comes to the end result.

Bake a cake with frigid butter and eggs and you may end up with something

resembling a pancake. That’s why some recipes call for “room

temperature” ingredients, a frustratingly general concept, especially

from a scientific point of view. Baking with room temperature butter helps to create "fluffiness." Too warm or too cold butter can result in either too few air bubbles, or air bubbles with don't hold their shape and flatten quickly.

Eggs are also crucial in giving loft to baked goods. The white of the

egg is 90 percent water and 10 percent protein; when you beat an egg,

it’s the protein that traps the air bubbles, and when incorporated into

baked goods, these bubbles expand in the heat of the oven. Egg whites

can be whipped up to eight times their volume, but this maximum

air-trapping happens only when the eggs are warm; in warm eggs, the

whites and yolks are looser, so it’s easier to incorporate air into them

(which is the whole point).

Warmer eggs are also better when

you’re mixing batter for cakes and cookies, because if you introduce

cold eggs to a warmer butter-sugar mixture, the fat in the butter could

harden. That would impede integration of the butter and eggs, which is

why you’re creaming them to begin with.

But you do want your eggs

to be cold if you need to separate the whites and yolks. Cold eggs are

easier to separate, so if your recipe calls for the yolks and whites to

be separated, do it before warming the eggs.

So now that I have told you all that I can about the science of baking and shared all of my wisdom in great cake bakery, I think it's only fair that I share my absolute favourite cake recipe with you.

It's a deliciously buttery sponge, filled with fresh raspberries and baked

into two moist layers. Sandwiched together with a lovely vanilla butter

cream icing and some seedless raspberry jam, and then drizzled with

more sweetness. This is one very moreishly scrummy cake.

*Raspberry Celebration Cake*

Cuts into 12 scrummy slices

This

is the cake I always bake for summer birthdays. A light moist sponge,

filled with lovely raspberries, butter cream icing and seedless

raspberry preserves. Top with a sweet glaze and serve with more

raspberries.

For the Cake:

• 175g of caster sugar (3/4 plus 1/8 cup)
• 175g of butter, softened (13 TBS)
• 4 large free range eggs, separated
• 100g self raising flour (a scant 3/4 cup)
• 1 tsp baking powder
• 100g ground almonds (1 scan't cup)
• a few drops of almond extract
• 125g of fresh raspberries (a heaped cup)
• For the buttercream:
• 75g of butter, softened (1/4 cup approx.)
• 125g icing sugar, sifted (about 3/4 cup)
• few drops vanilla
• For the glaze:
• 100ml icing sugar sifted (1/3 cup approx.)
• water to thin
• Also about 4 heaped dessertspoons of seedless raspberry jam
• Preheat
• the oven to 180*C/350*F/Gas mark 4. Butter two 8 inch sandwich cake
• tins. Line the bottoms with parchment paper. Set aside.
• Cream
• together the butter and sugar until pale and fluffy. Beat in the egg
• yolks. Sift the flour and baking powder over the creamed mixture and
• then fold in using a metal spoon. Fold in the ground almonds and

exract. Fold only until all traces of the flour have disappeared.

Beat

the egg whites until they just hold their shape. Fold them in gently,

by thirds, being careful not to overmix and lose the lightness of the

whites. Lightly fold in the berries. Divide between the two prepared

cake tins and level off carefully.

Bake in the heated oven for 30

to 35 minutes, just until they test done. A toothpick inserted in the

centre should come out clean and they should spring back when lightly

touched on top.

Remove from the oven. Let cool in the tins for

five minutes, then tip out onto wire racks, peel off the baking paper

and allow to cool completely.

Make the buttercream by beating together all the ingredients until smooth and creamy.

Place

one cake, bottom side up on a cake plate. Spread completely with all

the buttercream. Spread the raspberry jam over top of the buttercream

and then top with the other cake layer, placing it right side up. Whisk

together the icing sugar for the glaze and enough water to make a

smooth drizzable mixture. Drizzle decoratively over the top of the

cake. Allow to set, then dust with more icing sugar if desired.

Have a great weekend!