A basic cake recipe has the following ingredients: flour, sugar, butter, eggs, vanilla extract, baking powder, salt and milk. We are all pretty familiar with these items and can follow a cake recipe quite easily. But do you know how each ingredient contributes to your baked cake and why. If you understand how each ingredient plays a role in your cake you can manipulate them to get your desired cake texture, density and taste.
Flour – Flour provides the structure for your cake. When mixed with a liquid and baked the proteins in flour bond together to form the cake. When baking a cake, it’s best to use cake flour. Cake flour has fewer proteins to allow for a fluffier structure.
Sugar – Sugar adds sweetness of course, but it also helps the browning process.
Butter – Butter or other fats, such as oil, create the texture of your cake. The fats coat the proteins in the flour. While butter will give you a richer taste, oils are better at coating the proteins and as such will generate a moisture texture. Butter is best creamed at room temperature. If too cold or too soft your air pockets will not whip up correctly (see baking powder).
Eggs – The whites of the eggs act as a leavener, while the yolk adds richness and moisture. It’s important that your eggs be at room temperature when combining your ingredients, this will allow them to mix correctly with the sugar and butter.
Vanilla Extract – Vanilla adds sweetness and flavor
Baking Powder – Baking powder is a leavener. It releases carbon dioxide to create air bubbles that act to puff up your cake. Creaming butter allows the butter to whip up and create opportunities for air bubbles.
Milk – Milk helps with the moisture of the cake but also contributes to the texture by bonding with the proteins in the flour. You could also use buttermilk. The acidic properties in buttermilk react to the baking powder releasing even more carbon dioxide, contributing to a fluffier cake.
Salt – Salt balances the sweet taste in a cake and helps to enhance the other flavors.