All About Flour

Wheat flour is the backbone of the baked goods we love.

Brown Rice Flour Blend

Photo by Buckwheat Queen

The Two Types of Wheat
There are two types of wheat: hard and soft. The key difference between them is protein content. Hard wheat is higher in protein than soft wheat–and it is the protein that contains the gluten that allows breads and other baked goods to rise.

Where wheat is grown can determine protein content: Northwestern U.S. and western Canada produce hard wheat that’s very high in protein, while the southern U.S. states grow a softer wheat with less protein.

All-Purpose Flour
All-purpose flour includes a happy balance of hard and soft flours. And as the name suggests, it is a type of flour that lets you make a wide variety of baked goods–cookies, cakes, muffins, quick breads, biscuits, and pie crusts–without having to stock up on multiple types of flour.

One cup of AP flour = 4.5 oz (128 g)

Apple Strudel Muffins

Photo by Shalaine_1

Bread Flour
But with flour, one size doesn’t always fit all. One type of flour is best for baking bread, another type for pastries. Bread, for example, benefits from a high-protein flour.

When combined with water and developed by mixing and kneading, the gluten becomes elastic and stretches around gas bubbles produced by the yeast. When gas bubbles expand in the oven, the gluten goes along for the ride. The result is a nice fat loaf of bread.

Interestingly, of all the grains, wheat is the only one that packs gluten-producing proteins. To rise properly, breads made with other grains (like rye, corn, or oats) must be fortified with wheat flour or gluten.

Note: As a home baker, you can ignore language on bread flour labels saying “first clear flour,” “patent flour,” and “high gluten flour.” You’ll be fine with the blend of bread flour in any national brand.

One cup of bread flour = 4.8 oz (136 g)

Jo's Rosemary Bread

Photo by AbbyGirl

Pastry Flour
Pastry flour is a medium-protein flour that produces tender pie crusts. If you use a flour with too much protein, your pastry can become tough; too little, and the pastry can be brittle and hard to work with. Medium is just right.

In a pinch, you can make your own version of pastry flour by combining one part cornstarch to two parts all-purpose flour.

One cup of pastry flour = 4.25 oz (120 g)

Beer Batter for Fish

Photo by KGora

Cake Flour
Cake flour is a lower-protein flour that’s also bleached with chlorine, which alters the structure of the starches and fats and makes the flour slightly acidic. Unfortunately, substituting all-purpose flour in recipes that have been specifically formulated for cake flour will not produce happy results. Always sift cake flour before using it in a recipe.

One cup of cake flour = 3.9 oz (111 g)

Heavenly White Cake

Photo by cupcakesandc

Whole Wheat Flour
Whole wheat flour contains all of the nutrients found in the wheat kernel and results in dense, hearty baked goods. If 100% whole wheat bread tastes a little bit too healthy for you, try a ratio of half whole wheat, half bread flour.

Note: You might need to adjust your liquids to hydrate the flour fully (use more water if you’re adding whole wheat flour to a recipe, less if you’re substituting bread flour for whole wheat).

One cup of whole wheat flour = 4.25 oz (120 g)

Henry and Maudie's Oatmeal Cookies

Photo by B Spradley

Self-Rising Flour
Self-rising flour is used for quick breads, biscuits, muffins, and pancakes. It already contains baking powder, so don’t need to add any leavening agents.

To make your own self-rising flour, add 1½ tsp baking powder per cup of flour (or 5-7 g of baking powder per 100 g of flour).

Mayonnaise Biscuits

Photo by BEAN42069

Bread Machine Flour
Special bread machine flours are generally just high-protein flours, although some brands might contain dough conditioners like malted barley flour (diastatic malt powder), ascorbic acid, or lecithin.

Cracked Wheat Bread II

Photo by pomplemousse

Bleaching and Bromating  

Freshly ground wheat might smell great, but it doesn’t make an optimum loaf: as flour ages, it creates stronger gluten, resulting in a more elastic dough and a lighter loaf. Aging also changes the color of flour from pale yellow to white. Millers have sped up this aging process with chlorine and ascorbic acid (vitamin C) , which also helps the flour look whiter.

More About Wheat
The wheat berry is made up of bran, germ, and endosperm:

  • The bran is the hard outer shell that covers the wheat berry. An excellent source of fiber, the bran also contains most of the minerals. Because the bran has sharp edges, which interfere with gluten development, it is removed during milling–and then often added back in later.
  • The germ is the part of the grain that would become the plant. Wheat germ is very high in protein and B vitamins. It is removed in the milling process because its high fat content causes the flour to become rancid more quickly. Wheat germ should be stored in the refrigerator.
  • The endosperm is the food that the seed would consume on its way to becoming a plant. The flour that we use for baking, unless it is whole wheat, has had the germ and the bran removed. The remaining endosperm is composed mostly of starch and protein.

Protein Contents of Wheat Flours
U.S. and Canada

  • All-purpose flour (nationwide) 11-12%
  • All-purpose flour (Southern U.S.) 7.5-9.5%
  • Bread flour 12-13%
  • Whole wheat flour 11-15%
  • Pastry flour 8-9%
  • Cake flour 7-8%
  • Vital wheat gluten 70-85%

European Flours

  • Italian soft wheat, Type 0 or 00 11-12%
  • French Type 55 (blend of hard and soft wheat) 9-10%
  • English plain flour 7-10%

About Vital Wheat Gluten
If you don’t have the storage space or don’t bake often enough to buy several different types of flour, you can buy a small bag of gluten flour.

  • By adding about a tablespoon of gluten for every cup of flour in your recipe, you can make your all-purpose flour have the protein level and strength of bread flour (follow package instructions).
  • It’s expensive, but a little goes a long way. Gluten is available at health food stores and some supermarkets; brands to look for are Bob’s Red Mill, Arrowhead Mills, and Hodgson Mill.

More Types of Flour
Allergies to gluten have become more commonly diagnosed; they’re more often found in people of northern European and Scandinavian heritage. People with Celiac disease have trouble digesting the proteins found primarily in wheat flour but also in rye, oats, and barley.

Editor’s Note:
The natural oils in flours, especially whole grain flours, can spoil and turn rancid. Flour should be stored in the refrigerator or freezer if you bake infrequently. It should smell and taste “wheaty,” not musty or stale.