Virtually any grain, bean, nut, or starchy food can be ground, and, when it’s fine enough, that product can be called “flour.” But even if the name is appropriate, “flours” vary so much in different ways — flavor, texture, baking properties, color nutrition . . . really, everything — that you must understand the differences if you’re going to cook with anything other than standard all-purpose white flour. Substitutions, even partial substitutions, are only rarely straightforward.
Having said that, this is a joyous and fun world to explore, filled with possibilities. To get you started, here’s a run-down of the most common flours, as well as some specialty flours that are becoming more mainstream; see, too, the chart with some basic guidelines for substituting on page 576.
Wheat — especially hard wheat — contains the most gluten, and is therefore best for bread-baking. Barley, spelt, emmer, faro, and rye also contain gluten, in smaller amounts. (For a fuller discussion of gluten, see “The Magic of Gluten,” page 573.)
The workhorse of flours, made from the endosperm of wheat, usually a combination of hard and soft. It may be enriched with vitamins and nutrients to compensate for those stripped away during the milling process. It contains 8 to 11 percent protein, and is a good choice for cakes, cookies, pastries, noodles, quick breads, and yeast breads. It should be said that for the most part this is a commodity product, varying little in quality (at least in predictable quality) and far from the highest-character flour you can use. But it is all-purpose; almost everyone uses it at some point.
Milled from hard wheat, bread flour has more protein than all-purpose (up to 14 percent), and greater gluten strength (see “The Magic of Gluten,” page 573), which makes it the flour of choice for elastic, easy-to-handle doughs that produce a chewy crumb and sturdy crust. Typically unbleached, bread flour is sometimes conditioned with ascorbic acid, which can make the finished dough taste slightly sour.
Milled from soft wheat, these flours have a low protein content (generally about 9 percent for pastry flour, and slightly less for cake flour). This means doughs and batters don’t develop much elasticity, resulting in a tender, delicate crumb in cakes and flakier pastries. Minimal handling enhances those qualities. (You’ll sometimes see something called self-rising flour, which is soft wheat flour mixed with salt and baking powder; it’s used as a shortcut to make biscuits and quick breads, but you don’t need it.)
Made from red wheat, this is produced by grinding all three components of the wheat kernel — the bran, germ, and endosperm. This means more fiber and nutrients than all-purpose flour (and up to 14 percent protein), as well as way more flavor. Whole wheat flour produces heavier baked goods than white flour — the germ and bran have no gluten, and retard its development — so in most cases it’s best to combine it with white flour in recipes. (Having said that, 100 Percent Whole Wheat Bread, page 602, is a revelation, and white whole wheat flour, below, is more forgiving.) Whole wheat flour can be milled from ultra-fine to coarse; though the most common supermarket types are relatively coarse, finer grinds produce a more even texture and behave more like all-purpose and bread flour.
This is milled from soft wheat, with about 10 percent protein. Like its white flour counterpart, it produces a delicate crumb in cakes and pastries, but with the characteristics of whole wheat, meaning more flavor and more density.
Milled from white wheat instead of red wheat, which gives it a relatively mild flavor; but it’s still whole wheat, so has the nutritional advantages and the baking characteristics of “regular” whole wheat, which means most baked goods relying on it are on the heavy side.
Most barley flour is whole — it contains the germ, endosperm, and bran — and contains gluten, though much less than wheat flour. It has a slightly sweet, nutty flavor (and loads of soluble fiber), and has been relied on in bread baking for centuries. In bread-baking, use it with high gluten flours to make up for its low gluten levels.
This is graded dark, medium, or light, depending on the strain of rye and how much bran and germ have been milled out. The darker the flour, the stronger the flavor and the higher the protein and dietary fiber. Pumpernickel flour (some brands sell it as pumpernickel meal) is coarsely ground rye flour, with much or all of the bran and germ included. Rye has a low gluten strength and a tendency to produce gumminess (it’s tricky); for that reason, it’s usually used in combination with a good gluten-forming flour, like bread flour.
A high-protein flour made from ground spelt, an ancient variety of wheat, with a pleasant nutty flavor and relatively low gluten levels. You can find both white and whole grain spelt flour.