Have you ever wondered what the difference between cake flour, bread flour, and pastry flour is? Is it ok to substitute all-purpose flour that call for a specific flour type? These are questions that I get asked often.
Choosing the correct flour is about controlling the amount of gluten in your dough. Gluten is a protein structure that makes dough both firm and elastic. Bread flour comes from “hard” flour, which has a higher protein content (produces more gluten) making it perfect for bread, pizza dough, and any recipe that needs a little more elasticity and cohesion.
Pastry flour is made with “soft” flour, which has a much less protein content and produces less gluten. Dough made with pastry flour is tender, flaky and doesn’t hold together firmly. That’s a good thing because no one wants a rubbery piecrust! Cake flour has even less protein content than pastry flour, but not by much. It has just enough protein to give the cake a little structure, but not enough to make it tough.
All-purpose flour is a blend of “hard” and “soft” flours, which falls in the middle of the gluten spectrum, and works well in most baked goods. Your cakes might not be quite as tender, but in most cases they’ll still come out beautifully. It’s all a matter of degree. Cookies, piecrusts, muffins, quick breads, and scones all do well with all-purpose flour.
Gluten development is also the reason why recipes instruct you not to over mix your dough. Once you add water or any other low-fat liquid to flour, gluten bands start forming and the more you knead or stir the dough, the more these elastic bands start connecting. If you are using all-purpose flour in a cake or piecrust, make sure to stop mixing just when everything comes together.