Flour 101: Varieties of White Flours

Every cook and baker has used a form of flour at some time. As a formally trained Pastry Chef, before joining Penn State Extension, I often get asked what the difference is between white flours, and in which recipes a home cook should be using each type of flour.

Starting with the wheat plant, from which most flour is made, the wheat head (seeds) consists of three parts: the germ, the bran, and the endosperm. Making white flour requires the bran and germ to be removed, leaving the pale endosperm. White flours are more shelf-stable than whole-wheat flour and have a milder flavor, though they have reduced nutrients than their whole-wheat counterpart, which includes the bran, germ, and endosperm. Flour primarily comprises carbohydrates and multiple proteins. For the home baker, gluten (gliadins and glutenins) is the critical protein of importance. When a batter or dough is kneaded or mixed, the protein develops into gluten strands and becomes elastic, providing structure to baked goods. The leavening agent (air, steam, yeast, baking powder, and baking soda) provides the push to make your baked goods rise, but it is the flour that holds the shape and prevents it from collapsing. The addition of fats in recipes interacts with gluten, preventing long gluten strands from forming.

Next, let us define the terms “bleached" and “unbleached" and their effect on baked goods. The milling of the endosperm into flour produces a yellowish-colored product that is not visibly appealing. To bleach flour (whiten the color), manufacturers add a maturing agent such as benzoyl peroxide. This process also further refines it, producing a softer texture. Whereas unbleached flour is naturally aged, but only for a short time after being milled, it typically has an off-white color when purchased, though it can whiten while being stored in your home. Since it has not gone through the additional processing step as for bleached flour, it can have a courser grain. What is essential to know for the baker is that most recipes are formulated based on “bleached” flour. If you prefer unbleached flour, your product may be slightly denser or have a courser crumb. To offset this effect, eliminate 1-2 tablespoons per cup of flour in a recipe.

Do not run to the store just yet; there are still varieties of flour to unpack!

The most common and readily available white flours are all-purpose, bread, and cake flour. Other not as common are pastry flour and high-gluten flours. What makes each of these flours different? It all comes down to the protein (gluten) content of each flour. According to Pyler & Gorton (2020), protein content in flour can range from 6% to 18%. The more protein in flour, the stronger the flour, enabling the product to develop the long strands of gluten to capture and hold air pockets (think of Italian bread).

In contrast, lower-protein flours contribute to a soft, delicate texture. Keep in mind that different brands of flour fluctuate in their protein content as well. Below, I have listed the types of flour from the highest to lowest protein content. Cooks can also check out manufacturers' websites, which provide protein amounts for the different types of flour they produce.

High-Gluten Flour

High-gluten flour has the highest percentage of protein of the consumer flours readily available and is mainly used only in yeast products. The development of gluten in high-protein flour produces long gluten strands that enable a dough to stretch without tearing, like when making thin pizza. It also creates terrific crusty bread, the kind the leaves lots of crumbs behind while eating (think of baguettes). If high-gluten flour is not available in your area or storage space is an issue, bread flour is an equal exchange cup for cup.

Bread Flour

Unless you are an avid pizza or crusty bread maker, bread flour is your best choice for yeast dough baking. It, along with its high-gluten complement, has an off-white color. Generally, bread flour has 1-2% less protein than high-gluten flour. It provides an excellent structure to nearly any bread and a nice crust. A variety of yeast dough recipes use bread flour, such as rolls, loaves of bread, English muffins, and so much more.

Here's a baking tip: keep bread flour on hand and use it for dusting countertops when hand kneading and dusting the bowl for resting and rising yeast doughs.

All-Purpose Flour (also known as Occident Flour)

All-purpose flour is the workhorse of every home kitchen. Its mid-range gluten content makes it super versatile, from thickening liquids to making cookies, pies, and pastries, and yet it is strong enough for soft yeast dough (think of yeast recipes with eggs). Overall, this flour will meet most of your cooking and baking needs for the casual baker.

Self-Rising Flour

Self-rising flour is either pastry flour or all-purpose, depending on the brand you buy. It has baking powder and salt added by the manufacturer. Self-rising flour is a convenience, yet it can be problematic. First, there is no sure way of knowing exactly how much salt and baking powder is in the brand you are buying. Second, if you store it in the wrong conditions, the baking powder can lose its potency, causing flat baked goods. My suggestion is to make your own. For every 1 cup of flour, add 1½ teaspoons of baking powder and ¼ teaspoon of salt.  Self-rising flour should only be used in recipes that specifically call for self-rising flour.

Pastry Flour

Pastry flour has a slightly higher protein content than cake flour. To save storage, blend your pastry flour as needed, mixing 50% cake flour and 50% all-purpose flour to replace the pastry flour in the recipe. All-purpose flour can replace pastry flour in nearly any recipe.

Cake Flour

Cake Flour has the lowest gluten content and goes through a unique process compared to other flours, allowing it to hold liquid and sugar. Its soft fine texture makes it essential in recipes that produce a delicate final product—a must for angel food cake, meringue, chiffon cake, and soufflé.

Finally, here are a few important notes. If you are a novice baker, follow recipes as printed for best results. For experienced bakers that want to experiment, have fun!  The same type of flour from a different brand can produce a different baking result. The finished product could seem dryer or denser; the flour may be the reason. If necessary, do not be afraid to adjust to compensate. Store all flour in airtight containers in a cool, dark place, or the freezer for long-term storage. As flour ages, it loses strength, and whole-grain varieties can become rancid.

Armed with the knowledge of the differences between the many varieties of white flour on the market, feel confident in your ability to make the best selection for your next baking project. Good luck and happy baking!

Reference

Pyler, E. J., & Gorton, L. A. (2020). Baking Science and Technology Volume 1 Fundamentals and Ingredients (4th ed., Vol. 1). Sosland Publishing Company.