Today, we're going to continue with our baking lessons (have fun, Lowki...haha). This time, let's tackle cakes, and the science of making them properly. Yes, it's science...measuring accurately, combining properly...bet you never thought that those boring lectures you suffered through in high school would come in handy at home, eh?
Cake batters are precise combinations of ingredients; in fact, a scratch cake recipe can be more accurately called a scientific formula. The ingredients are combined in a specific way to form the structure of the cake. Scratch cake formulas include shortened cakes (including pound cake), foam cakes, and a one-bowl method, which uses either solid shortening or oil. Cakes made with mixes can be just as good as scratch cakes, especially if ingredients like finely chopped chocolate or sour cream are added to the mix (if you choose to add something with a liquid content, be sure to adjust your baking time to allow the added moisture to cook out).
Some cake recipes call for cake or pastry flour (a good example would be Swan's Down flour). This is a flour that is grown especially to have a low protein content. Remember, that low-protein equals low gluten content equals more tenderness. If you can't find cake flour, or want to bake a cake but don't have any on hand, you can substitute 3/4 cup plus 2 Tbsp. of regular all-purpose flour and 2 Tbsp. of cornstarch. Sift this mixture together, then measure your homemade pastry flour cup by cup.
Preparing your pan is crucial, too. You can grease the pan with solid shortening or UNSALTED butter (if you use salted butter or margarine to grease a pan, the cake will stick, guaranteed) and dust with flour, or you can make your own pan coating mix by beating together 1 cup solid shortening such as Crisco (not butter flavored, NOT butter or margarine) with 1/2 cup flour. Store this in the fridge and use it to grease your pans. I've recently become enamored of the nonstick sprays that contain flour, such as Baker's Joy; they work really well, and it makes it so easy!!
Now on to the types of cakes. Typically they fall into the aforementioned catagories...shortened, foam, and one-bowl. Each presents a unique way to make a cake, and each are equally yummy.
These cakes are based on a combination of fat and sugar, combined by creaming. The sugar crystals create tiny holes in the shortening, which will be filled by carbon dioxide and steam when the cake is baked. This is called aerating the fat. Flour and eggs provide structure with proteins and starches, which coagulate in heat, setting the structure in tiny bubbles around the CO2 and steam. This is the basic method for making traditional shortened cakes:
Cream together the butter or other fat and sugar.
Add eggs and liquid flavorings; beat well.
Sift flour with leavening ingredients, salt, and dry flavorings.
Alternately add the flour and liquid to the fat/sugar/egg mixture, making sure the ingredients are combined before adding the next ingredient. The dry ingredients are usually divided into fourths; the liquid into thirds. So if a cake calls for 2 cups of flour and 1 cup of liquid, you would add 1/4 cup of flour, then beat the mixture so the flour disappears. Then add 1/3 cup of liquid, and beat the mixture until the liquid disappears. Continue in this matter, making sure you begin and end with dry ingredients.
These cakes are based on a foam made from beaten eggs, egg whites, or whipping cream. Foam cakes include angel food cakes, chiffon cakes, and sponge cakes.
Angel Food Cakes
These cakes are made from egg whites, sugar, flour, cream of tartar, salt, and flavorings. Cream of tartar makes the mixture more acidic, forming a favorable environment for protein bonds. Sugar adds flavor and tenderness, and helps form and stabilize the protein bonds. This is important: the bowl and all utensils which come in contact with egg whites must be totally clean and free of grease. Fat will destroy the foam by interfering with the protein bonds of the egg white.
Have the whites at room temperature for the best volume; the protein bonds will be more relaxed and the foam higher. Start beating egg whites slowly, then gradually increase the speed of the mixer as you add sugar. Flour and flavoring ingredients are added by gently folding into the egg white foam. Using a spatula or wide spoon, cut down the side of the bowl, then scoop along the bottom of the bowl, gently turning the mixture, until the dry ingredients are incorporated. This is a delicate process, but take your time and you can do it!
Angel Food cakes must be baked as soon as the batter is finished. The pans are not greased, so the delicate structure can grab onto the pan sides as the steam forms and the air bubbles increase. Some recipes tell you to cool the cake upside down. This stretches the protein bonds as they cool so the cake doesn't collapse. Don't worry - the cake won't fall out of the pan as it cools.
Chiffon cakes are angel food cakes with egg yolks and vegetable oil (not butter or margarine) added. They still depend on an egg white foam, but the fat makes a more tender cake that stays moist longer. It is very important to make sure that the egg white foam is beaten until very, very stiff. The foam provides most of the structure for the cake.
Sponge cakes are made of whole eggs, and use no other leavening ingredient. Egg yolks are beaten with sugar to incorporate air into the batter, then the whites are beaten with more sugar for stability, structure, air, and volume. The two mixtures are folded together, with flour added for structure.
One Bowl Cakes
It was a big deal in the 1960s when home economists discovered that cakes could be made by simply combining all ingredients in one bowl and beating them together for an extended period of time (4-5 minutes on high speed) to incorporate air, instead of the method of creaming the shortening and alternately adding liquid and dry ingredients. Many cake recipes use this method. There is also the two-stage method of cake making, a variation of the one-bowl cake. The dry ingredients are combined in a mixing bowl, the fat and liquid are added, then eggs are beaten into the batter. This method 'greases' the proteins in the flour in the first step, so it's harder for them to combine with each other, making a very tender cake.
I hope this has provided some insight for you all into just how fascinating cake making really is. It is fun, too...even your kids can get involved, and find the joy in creating something for the whole family. Remember, if you have questions at any time, PLEASE let me know. Sometimes I get a little rushed, and may not always explain things fully.