Those of us who like to bake – that was not always the case for me – have at least at sometime in the past, been confused about “gluten” and “protein” levels in different flours. What’s the difference between Bread flour and Pastry flour, for instance.

First, lets start with “gluten”. “High protein flours are generally recommended for yeasted products…” that require a lot of structural development in order to keep their shape and strength: The development of gluten. (2004, Baking Illustrated. Page 1) It is the gluten produced by the protein in the flour that produces elastic sheets in the dough that expand with the gas produced from the yeast. Flours are categorized by their protein levels.

That said, let’s look at the protein levels, or the ability of a flour made into a dough, to produce high glutens. The two are related.

Bread Flour – Protein content about 14 grams per cup. (There are 27 grams to the ounce) This is the flour of choice for yeast doughs. A slightly higher proportion of protein is available to professional bakers, such as your local pizza maker. In most cases, if a recipe calls for a high gluten flour, bread flour will work just fine.

All-Purpose Flour – Protein content 10 – 12 grams per cup. This staple flour is usually a blend of high gluten hard wheat and low gluten soft wheat flours. All-Purpose flour from the supermarkets, Pillsbury and Gold Medal – flours milled in the northern United States – have the 10-12 grams per cup. However, there are variations of All-Purpose flours between brands. For instance, King Arthur All-Purpose flour and Hecker’s have protein levels as high as 12 – 13 grams per cup. Almost as high as Bread flour. Southern brand flours, such as White Lily are low in protein, about 9 grams per cup. When a recipe calls for All-Purpose flour, you can use either bleached (chemically induced whiteness) or un-bleached (no chemical additives).

Cake and Pastry Flour – The lowest of the protein levels at about 8 grams per cup. These flours are used when a tender crumb is desired. Cake flour is chlorinated to make it whiter, Pastry flour is not. Cake flour can be found in most grocery stores, Pastry flour is not always available. If you cannot find Pastry flour, combine 3 parts of All-Purpose flour with 1 part of Cake flour.

So there you have a short discussion on the different types of flour and why some are better suited for breads and the like and others are better suited for piecrusts and cakes.

1996 Baking With Julia, William Morrow and Company, New York

2004 Baking Illustrated, Editors of Cook’s Illustrated, America’s Test Kitchen,
Brookline, MA

2006 Bob’s Red Mill Baking Book, John Ettinger, Running Press, Philadelphia, PA