Why You Shouldn't Be Substituting Cake Flour In Recipes
At first thought, cake flour may seem like an impractical addition to your pantry and an unnecessary buy meant for only serious cake bakers to use. So, when recipes call for cake flour, it's easier to either skip that recipe completely and opt for a more basic one or rely on the good old cake flour substitution hack — one cup minus two tablespoons of all-purpose flour plus two tablespoons of cornstarch makes up for one cup of cake flour. Seems like a lot of math to do!
Aside from the math that goes into substituting cake flour with all-purpose flour, using cake flour instead of the latter has many advantages. Adding cake flour will make your cakes more tender, fluffier, and basically make you seem like a cake-baking pro. And so, when recipes call for a large amount of cake flour, it's probably for the best to stick with it (via Bon Appétit).
What makes cake flour irreplaceable?
According to Bon Appétit, cake flour is milled from soft wheat, which is low in protein. This means cake flour has a much lower protein content at 5% to 8% as compared to all-purpose flour which has between 10% to 13% protein. Cake flour's comparatively low protein content means that it does not produce as much gluten as all-purpose flour does. Epicurious explains that since cake flour produces less gluten, using it will make your cakes lighter, softer, more tender, and make them rise higher while still giving them just enough structure.
Using cake flour has another perk. Since it is a finely ground flour and has a larger surface area, cake flour can absorb a larger amount of liquid. This, Bon Appétit says, makes it possible for you to add more sugar to your cake without compromising its structure (since adding more sugar requires you to add more liquid as well). And adding more sugar means that your cake will turn out to be moister, have a finer crumb, and will last longer.
According to Kitchn, cake flour works especially well when baking chiffon or an angel food cake. If you decide that it's time to finally add cake flour to your pantry, try your hand at this angel food cake recipe which will make your cake flour shine.