A Culinary Guide to Flour Types: Difference Between Unbleached and Bleached Flour, and How to Use Wheat, Oat, Bran, Pastry, and All-Purpose Flour

Flour is the powdery result of grinding wheat, corn, rice, or seeds (or dried roots like cassava). It’s used in many different culinary applications, from baked goods like breads, cakes, and pie crusts to roux for sauces and airy batters. Most conventional flours are made from wheat kernels (or wheat berries), which consist of an endosperm, a germ, and a bran.

Bleached flour is flour that has been treated with a whitening agent like benzoyl peroxide. Some flours are also treated with a maturing agent, which can either dampen or enhance the gluten development by manipulating the starch content of the flour itself, usually by oxidizing it, which allows flour to absorb more liquid and thus transform into a thicker dough.

Unbleached flour is any flour that has not undergone this bleaching process and does not contain any trace preservative chemicals as a result. (And “white flours” don’t always mean bleached: the term refers to refined flour that does not include the bran or germ from the wheat kernel.)

Protein content in flour is informed both by the type of wheat grain that is used, and whether or not the flour has been enriched. The amount of protein determines how much gluten can develop in the flour when kneaded and baked. Hard wheat, for example, has a protein content range of 10 to 13 percent and produces bagels and chewy breads with crackling crusts; softer strains of wheat flours, somewhere around 6 to 7 percent are best for things like cakes and cookies, where stretchiness is less a priority. Additives like ascorbic acid or potassium bromate are sometimes added to flours to enhance gluten development.

Flour is best stored in an airtight glass or plastic container, kept out of direct sunlight in a cool, dry place. If you get freshly milled flour from a CSA or local mill, use it quickly while it's fresh. Even shelf-stable, treated flours can and will go rancid eventually—so don't go keeping the same bag for years on end.

• ALL-PURPOSE: As the reigning, most-popular flour, AP flour is a white flour containing only the endosperm of the original wheat head. While it’ll last longer than other whole-grain flours, it doesn’t clock in much nutritional value as a result. That being said, it has a solidly mild flavor and works well in just about everything you can think of. Try making this easy homemade bread recipe with all-purpose flour.
• WHOLE WHEAT: As a direct contrast to all-purpose, whole-wheat flour is flour that includes the wheat germ, bran, and endosperm, making for a dense, flavor-packed flour that results in heavy-hitter, high-moisture loaves. It has a shorter shelf life than all-purpose flour. White whole wheat flour is made in the same way but from a winter white variety of wheat.
• RYE: A close relative of wheat, rye flour is a dark grain that imparts a deep nutty flavor. Rye breads like German pumpernickel or Danish rugbrød are good examples of the form. Because it doesn’t produce much gluten on its own, it’s occasionally combined with higher protein flours for a boost, which is why you'll sometimes find sourdough ryes.
• OAT: Oat flour is the result of grinding whole grain rolled oats down to a fine texture. As a gluten-free flour, it doesn’t have a particularly high protein content, making it a great choice for things that don’t require much of a rise, like quick breads and cookies.
• BREAD: Bread flour is flour with a particularly high protein content, up to about 14 percent. While yeast ferments during the early stages of baking bread, carbon dioxide gets trapped by the protein-bonded flour, resulting in stretchy dough with air pockets in the crumb.
• CAKE: For spongy, light-as-air cakes, the world gives you cake flour. Made from a soft wheat and ground incredibly fine, it has a low protein content (and thus, less gluten) compared with all-purpose, which will result in a lighter, loosely structured crumb. To mimic the effects of cake flour with all-purpose, remove 2 tablespoons of flour and replace it with 2 tablespoons of cornstarch, which will prevent the formation the gluten to a similar effect.
• PASTRY: Delicate pastries call for a delicate flour. Pastry flour, with its low protein-high gluten formula combined with a superfine consistency, is a great match for flaky viennoiserie like croissants.
• 00: 00 flour is a fine flour graded on an Italian milling system, intended for pizza and pasta making. While the soft texture is an immediate benefit, it’s the 12.5 percent protein level and corresponding gluten content that experts agree gives perfect pizza dough and silky noodles that just-right amount of stretch and snap.
  
• SELF-RISING FLOUR: Flour with leavening agents add airiness through small gas bubbles released in the dough. Self-rising flours are typically used for baked goods like scones, biscuits, or muffins, where an even, consistent puff is the goal.
• SPELT: Also known as dinkel or hulled wheat, spelt is an ancient grain that’s been around since 5,000 BCE. Nuttier and more complex in flavor than a standard whole-wheat flour, spelt is a great addition to all-purpose flour in everything from pancakes to quick breads.
• BUCKWHEAT: Earthy, savory buckwheat flour gives depth to crepes and blini, and it’s often used as a gluten-free alternative to other flours.
  
• RICE: Rice flour is ground white or brown rice kernels. It’s gluten free, and often used in blends or treatments like tempura to add a crisp, light texture. Edible rice paper is often made from brown rice flour.
• BARLEY: Subtly sweet barley flour is high in fiber and ranks lower than most other grains on the Glycemic Index.
• AMARANTH: Ground amaranth grain was a staple in pre-Columbian Mesoamerican cuisine. Flavor-wise, its nuttiness is similar to brown rice or whole wheat.
• ALMOND: Almond flour is also known as almond meal, finely ground almonds can be used as a substitute for many baked goods, especially in French patisserie. Though high in protein and fats, it is gluten free.
• CORN: Corn flour (rather than cornmeal, which has a coarser grind) is a versatile flour made from the bran, germ, and endosperm of maize. It makes for a deeply rich and buttery flavor in corn bread, and when treated with alkaline, it’s known as masa harina and can be used to make tortillas and tamales.

Ready to start baking? Learn the fundamentals of French pastry with Chef Dominique Ansel here.