Types of Flour: A Guide

As a practiced baker, I usually walk down the baking aisle at the supermarket with confidence. I know which flours I need and which brands I prefer. But over the last few months, faced with shelves devoid of my usual go-to flours, like good old all-purpose and bread, I’ve been left wondering what I can bake with the flours that are left, such as whole wheat, self-rising, and instant. I know I’m not the only one.

This moment serves as the perfect opportunity to explore flour in-depth and to demystify the flours you’ll find on supermarket shelves. All wheat flours are not created equal: Each flour has its own distinct qualities, from its protein content and how finely it’s ground to the variety of wheat it’s milled from, all of which affect the way it acts once made into a batter or dough. I’m going to break down the differences and show you, the home baker, which sack of flour to reach for, and when.

What Is Wheat?

Before diving into the similarities and differences between various wheat flours, it’s helpful to understand a little more about the grain they’re made from. Wheat is a type of grass plant that produces ears of grains—rows upon rows of seeds wrapped in papery husks (the chaff), which, over the last 10,000 years, humans have learned to cultivate, harvest, process, and transform into breads, noodles, fried doughs, and so much more.

Much like corn, you need to strip wheat grains of their husks in order to render them edible (or at least digestible). Wheat plants are considered mature when they turn a golden color, similar to straw. At that point, the stalks are cut and gathered into sheaves, or bunches, to dry as they ripen. Once dry, the stalks are threshed, loosening the grains, then winnowed, using air movement to separate the grain from the chaff (some less common varieties of wheat, like spelt, emer, and einkorn, have an inedible hull that also needs to be separated from the grain and removed). The resulting grains can be eaten whole—the stuff you'll find in a wheat berry, farro, or spelt grain bowl, for instance—or they can be processed further.

If you look closely at one of these whole grains, you’ll first notice a dark outer covering. This fibrous, protective outer layer is known as the bran and it’s loaded with B vitamins, a high amount of dietary fiber, and a good amount of protein. Peeling away the bran reveals the endosperm, which constitutes almost 85% of the kernel. It's composed largely of starch and protein, and serves as the food source for the germ, or embryo, hidden within. Comprising just 2.5% of the kernel, the germ is rich in essential fatty acids, protein, minerals, and vitamins B and E. Under the right conditions, the germ can sprout, or germinate, and grow into a plant, beginning a new cycle of life.

For our purposes, though, we’ll be talking about what happens when you mill that wheat (whether bran-on for whole wheat, or bran-off for white flours) into a powdery product known as—you guessed it!—flour.

How Wheat Becomes Flour

Though evidence exists that hunter-gatherers were bashing seeds into flour at least 32,000 years ago using a rudimentary process akin to pounding ingredients in a mortar and pestle, we can generally say that there are two prevailing methods for milling wheat into flour: stone milling and roller milling.

Stone-Milled Flour

Early stone mills relied on human or animal power to move a top "runner" stone against a stationary bottom "bedstone." This grinding movement was used to shear whole grains into smaller and smaller fragments—with one major catch. Even as stone-mill technology progressed and they came to rely on wind and water power, they required the watchful presence of a miller to ensure that the friction wasn't causing the stones to overheat. Subjecting flour to temperatures over 170°F (77°C) causes the fat in the wheat germ to rapidly oxidize and rancidify, resulting in the loss of vitamins and minerals, as well as a significantly reduced shelf life.

Unrefined whole grain flour that’s turned out of stone mills at the proper temperature is more golden than white, and it retains all of the grain’s vitamins, minerals, and fiber in the form of the bran and germ. But unrefined whole grain flour is also more prone to spoilage. For this reason, millers began using a process called bolting, in which they sift bran out of the flour to whiten, or refine, the flour and slow the onset of rancidity.

Though modern and mechanized stone mills are still used today to produce whole grain flours on a small scale, and are experiencing something of a revival, commercial operations rely instead on the more modern technology of roller milling.

Roller-Milled Flour

Roller mills were invented in Hungary in 1865, and introduced to the US in the 1880s. Initially powered by steam, today they run on electricity and operate by passing grains of wheat through pairs of rollers—a process that mitigates the high temperatures associated with stone milling (though grains may reach 95°F/35°C briefly, that temperature doesn't threaten to destroy any nutrients).

The first pass, or "break," as the industry calls it, through corrugated rollers cracks the kernel into pieces, which are then sifted and separated to remove the endosperm from the bran and germ. The endosperm is then sent through a series of smooth rollers to grind it to a finer consistency. This process of breaks, siftings, and grindings is repeated several times, with each producing different commercial grades of flours, or what the industry calls streams.

Roller milling produces four edible streams. The first two streams yield high-quality "patent" flour that consists of the innermost part of the endosperm and is free of germ or bran. The patent flour from different varieties of wheat can then be sold separately or blended with other flour to produce the bags of bread, all-purpose, pastry, self-rising, and cake flours available on supermarket shelves, which can last up to eight months stored at room temperature, up to one year if refrigerated, and up to two years if frozen. Since removing the bran and germ also removes a significant portion of the grain’s nutritional value, starting in the 1940s in the US, flours have been enriched with iron and B vitamins (niacin, thiamin, riboflavin, and folic acid) in order to compensate for lost nutrients.

The last two streams create lower quality flour—which the industry calls "clear"—comprised of the outer part of the endosperm. It’s higher in bran and germ (and thus protein) and slightly gray in color (not exactly living up to the name "clear"). Clear flour is commonly added to whole grain and rye breads (to which it adds strength and where its drab color can be hidden) and used in the production of vital wheat gluten.

Improving and Bleaching Flours

Freshly milled flour has a yellowish tint and "makes a weak gluten, a slack dough, and a dense loaf," according to Harold McGee, author of On Food and Cooking at Amazon. Small independent flour millers, like Maine Grains and Bluebird Grain Farms, and some larger flour operations, like Bob’s Red Mill, King Arthur Flour, and Heckers & Ceresota Flour, naturally age their flours. Naturally aging flour allows it to come in contact with oxygen, which both pales the flour’s pigmentation and encourages its glutenin proteins to form even longer gluten chains, meaning doughs made with aged flour will have greater elasticity. (If you want to nerd out on gluten, our exploration of how gluten works is a great place to start.) This process of air-aging takes several weeks and yields flour that’s labeled "unbleached."

At the turn of the 20th century, commercial flour mills sought to increase production by using maturing and bleaching agents to shorten that aging process; commercial mills, like Gold Medal, Pillsbury, and White Lily, chemically treat some flours to achieve the effects of flour-aging in just two days. Potassium bromate, a maturing agent, was first used to oxidize the glutenin proteins and improve the elasticity of dough. In many countries, potassium bromate is now banned as a food additive due to concerns over its safety for human consumption. Although it’s not banned in the US, mills began to replace bromate in the 1980s with ascorbic acid (vitamin C) or azodicarbonamide, which produce the same results. To replicate the whitening process, mills turn to benzoyl peroxide or chlorine gas. Benzoyl peroxide (which is more commonly known as a treatment for acne) is used in bread, all-purpose, cake, and pastry flours since it has no effect on their pH or their starch and protein behaviors; its effect is purely aesthetic (just like its effect on acne!). Chlorine gas is used exclusively in cake flour. In addition to whitening, the process of chlorination improves the baking properties of soft wheat flour by weakening gluten and lowering pH—which helps to produce a sweeter flavor, finer crumb, and a more aerated final product.

You might also notice two other ingredients—enzymes and malted barley flour—when scanning the ingredient list on a bag of flour. The addition of enzymes (proteins that can speed up chemical reactions or cause reactions to occur that might not happen otherwise) improves yeast fermentation, browning, and extends the shelf life of baked goods and breads. Malted barley flour—sprouted kernels of barley ground into flour—may also be added; it contains amylase, an enzyme that breaks down starches into sugars, which accelerates yeast fermentation.

Classifying Wheat: Hardness, Color, and Season

American farmers grow wheat varieties that are grouped into six major classes. The first five are all varieties of a species known as common wheat or bread wheat—hard red winter, hard red spring, soft red winter, hard white, and soft white—and account for 95% of wheat production worldwide. The last is durum, which is a different species of wheat that accounts for nearly all of the other 5% (species like einkorn, emmer, spelt, and khorasan wheats are grown in very limited quantities). To determine which type of wheat is the best match for a recipe, it’s important to understand how the hardness, color, and time of year when the wheat is harvested affect the flours that they produce.

Hard Wheat Versus Soft Wheat

We’ve touched on this in our guide to gluten, but the most crucial factor in selecting a wheat is its "hardness," or protein content. Hard wheat has a higher protein content (11-15%) than soft wheat (5-9%), meaning the former has more capacity for gluten development than the latter. For this reason, hard wheat is best suited for doughs that require a strong gluten network and produce an open, chewy crumb, while soft wheat is typically used for more delicate pastries and cakes. Its low gluten strength works well in chemically-leavened goods like muffins, biscuits, and cookies, all of which have a tight and tender crumb. You can feel the difference between these flours with your fingers—flour made from hard wheat has a granular feel, while flour made from soft wheat has a powdery texture.

Red Wheat Versus White Wheat

"Red" and "white" refer to the color of the bran. Red wheat contains tannins that lend it a slightly bitter, more robust flavor and a reddish color. White wheat, on the other hand, has no tannins (white wine, by contrast, just has lower levels than red), giving it a milder flavor and a light color. Although a wheat’s color is less important than its hardness, it can still affect the taste and appearance of baked goods. Of course, the distinction between red and white wheat is far more relevant in whole grain flours, which contain the bran, than it is in refined flours, in which the bran has been removed during processing.

Spring Wheat Versus Winter Wheat

The season that precedes the wheat’s name refers to when the crop is planted, which affects its compositional makeup. Winter wheat is planted in the fall and harvested the following spring or summer; spring wheat is planted in the spring and harvested in late summer. Winter wheat has a relatively low protein content (10-12%), so it’s often blended with soft wheat to make all-purpose flour. Gold Medal’s Blue Label, which combines hard red winter and soft white wheats in their classic all-purpose flour, has a protein content of 10.5%. Spring wheat boasts a higher protein content (12-14%), and is thus often ground to make bread flour or blended with winter wheat to produce an all-purpose flour. King Arthur’s all-purpose flour blends hard red winter and hard red spring wheats to produce an AP flour with a high protein content (11.7%) that is close to that of some bread flours.

Why Protein Matters

It's crucial to take protein levels into consideration when considering the perfect flour for a recipe.* Bread flour typically has a protein content of 12-14%, all-purpose ranges from 9-12%, pastry flour contains 8-9%, and cake flour has about 7-8%.

*Flour labels aren’t very forthcoming with information about exact protein content or wheat variety. To find this, you’ll need to dig deeper and go directly to the producer's website.

These protein percentages are an indicator of the gluten-potential of any given flour. Gluten, formed when wheat flour is mixed with water, accounts for the structure and texture in baked goods and breads. In general, the higher the protein content, the more gluten the dough can potentially develop.** This does not mean that high-protein flour is better than low-protein; rather, different types of flour are better suited for different purposes. At Serious Eats, we stress that "choosing the right flour is by far the most important decision you’ll make when it comes to how much, if any, gluten you want."

**One exception to this is whole wheat flour, which has a protein content between 11 and 15%. Although it contains plenty of protein, the presence of sharp, fibrous bran particles affects the final volume of the dough by tearing strands of gluten. That’s why 100% whole wheat bread can be incredibly dense.

High-protein flours perform well in airy, crusty loaves, but can spell disaster for tender biscuits. Low-protein flours lack the protein needed for chewy bagels and are best suited for tender and fluffy cakes.

Type of Wheat Flour	Protein Content
Whole Wheat	11-15%
Bread	12-14%
Durum	13%
00 (Doppio Zero)	11.5-13%
All-purpose	9-12%
Instant	9.5-11%
Pastry	8-9%
Self-rising	8.5%
Cake	7-8%

Common Types of Wheat Flour

For the purposes of this guide, I’m focusing on the most widely available bread and durum wheat flours in the US.* In general, you should try to use the exact type of flour called for in any recipe, especially if you're not an experienced baker. That said, experimentation with different flours can be fun and educational; just know a recipe may not work as expected if you deviate from its specifications.

*I specifically chose to avoid the inclusion of other wheats—einkorn, emmer, spelt, khorasan—in this guide since they aren't typically available at supermarkets and may need to be purchased directly from a miller. Grinder Finder is a great tool for sourcing these rarer flours in the US.

Whole Wheat Flour

Whole wheat flour makes up only 6% of all flour produced in the United States. Milled from hard red wheat, its protein content ranges from 11-15%. Much of the whole wheat flour you find at the supermarket has been processed in a steel roller mill: The three edible parts of the grain are separated, milled, and then recombined to approximate the natural ratio in the wheat kernel. Since it contains the germ and bran, it's darker in color, more assertive in flavor, and has a shorter shelf life (due to the bran and germ’s propensity towards rancidity). It works well in heartier recipes, like carrot cake, gingerbread, and homemade crackers, where its rich flavor and coarser texture are welcome additions. It can also be mixed with all-purpose or bread flours to create breads that have a lighter wheat flavor and a less dense crumb. We recommend King Arthur Whole Wheat Flour, a national brand that is widely available.

Graham flour, named after Dr. Sylvester Graham, a prominent figure in the early 19th-century health food movement, is a type of whole wheat flour that has a slightly coarser grind. With its nutty and sweet flavor, it works well in graham crackers and pie doughs. Whole wheat and graham flours can be used interchangeably in recipes, so if you have one or the other, don’t be shy about substitution.

Then there’s white whole wheat flour. Wait, how can it be white and whole wheat? White whole wheat flour is milled from hard white wheat, with a protein content around 13%. It contains the edible parts of the whole kernel, meaning it’s as nutritious as whole wheat flour. It’s lighter in flavor and color and works well in recipes that call for whole wheat or graham flour. Several commercial mills (Heckers & Ceresota Flour, King Arthur Flour, and Gold Medal) produce white whole wheat flour.

To ward off rancidity, whole grain flours should be stored in an airtight container in the freezer for up to six months, because cool and dark conditions with the least amount of exposure to moisture and air slow down oxidation.

Bread Flour

Of the refined wheat flours, bread flour—milled from hard red spring, hard red winter, or a blend of both hard wheats—has the highest protein content, ranging from 12-14%. Its high protein content contributes to strong gluten potential. When mixed with water, a gluten network emerges (absent any bran and germ that can tear strands of gluten) and does a fantastic job of trapping gas bubbles and forming air pockets, leading to a strong, elastic dough that will yield open, airy breads with a chewy texture. If you’re interested in baking bread, dinner rolls, and bagels, make sure to keep a bag of widely-available King Arthur Bread Flour on hand. We tested combining vital wheat gluten with all-purpose flour as a substitution for bread flour, and, in a pinch, it will work.

Durum

Known as macaroni wheat or semolina, durum wheat (Triticum turgidum) is in the family of wheat but is a different species from bread wheat. Descended from emmer, it’s a hard wheat with a high protein content that hovers at 13%. Although it contains a lot of protein, it lacks a specific set of DNA found in bread wheat, which makes the gluten it can develop more extensible and inelastic. This isn’t great for bread but it’s perfect for pasta. Its golden color comes from high concentrations of carotenoids, or pigments, which give the wheat a lovely, deep yellow hue.

Durum wheat flour is sold at different levels of coarseness. Coarsely ground semolina is commonly used for desserts, couscous-like pastas, and sometimes to prevent doughs from sticking to surfaces (pizza peels and sheets of fresh pasta are often dusted with semolina for this reason). Medium grind semolina flour is used to make Roman-style gnocchi, and pasta dough for shapes like orecchiette. Finely ground semolina flour, labeled "semola rimacinata," can also be used for pasta, but is primarily used in baking, for bread and focaccia doughs.

00 (Doppio Zero) Flour

Italian "doppio zero" (double zero) flour is highly sought after for pizza, flatbreads, focaccia, and pasta. (Italian flours use a grading system of 00, 0, 1, and 2, in which the numbers correspond to the fineness of the grind and the amount of bran and germ removed. On one end of the spectrum is Type 2, which is the coarsest flour containing the most bran and germ. On the other end of the spectrum is Type 00: It has the finest grind, a powdery texture, and contains very little of the bran and germ.)

Within Type 00, protein content fluctuates between 11.5 and 13% because of the proprietary blend of wheats used. Mulino Caputo, an Italian miller of flours that can be found in the US, produces a wide range of 00 flours, each of which is formulated for different purposes. Their 00 flours are labeled specifically for fresh pasta and gnocchi, for cakes and pastry, for long fermentation doughs, and for pizza. However, the ones you’ll mostly see in the United States are their Pizzeria flour in a blue bag and The Chef’s Flour in a red bag.

Both are highly desirable when making a traditional Neapolitan pizza. While you can substitute bread flour or all-purpose flour (neither of which is milled nearly as fine), or even King Arthur’s Italian-style flour (their version of 00 flour, which has a low protein content of 8.5%), it won’t produce quite the same results.

All-Purpose Flour

With its moderate protein content of 9-12%, all-purpose flour lives up to its name as the most versatile type of wheat flour available.

That isn't to say that all all-purpose flours are interchangeable, and they aren't suitable for all things. The protein content of each depends on the brand and the type of wheat used. King Arthur and Hecker’s all-purpose flours are milled from hard wheats, resulting in a higher protein content ranging from 11.4 to 11.7%, edging them up into the bread-flour domain. These flours are great for making bread and pizza, but their increased gluten potential makes them less appealing for delicate pastry doughs and batters.

Gold Medal and Pillsbury all-purpose flours blend hard and soft wheats, yielding a mid-range protein level of around 10 to 11%—perfect for cookies, pancakes, and pie dough, but also capable of producing a passable loaf of bread. White Lily uses soft wheat and has approximately 9% protein, making it closer in protein content to pastry flour than other all-purpose flours, and thus better suited for use in pastries and biscuits than in bread doughs. For these reasons, we recommend stocking Gold Medal’s Blue Label as a standard all-purpose flour because it provides a mix of protein and starch that we find to be the most versatile for a wide range of recipes.

Instant Flour

If you’ve heard of Wondra, then you’re acquainted with instant flour. Introduced in the 1960s by Gold Medal Flour, Wondra is made by a process called pregelatinization, in which low-protein flour is pre-cooked, dried, and milled into a super-fine powder. While it’s mostly used to instantly dissolve into any hot or cold liquids (no more lumpy gravy!) and as a coating for fried meat, fish, or vegetables because it produces delicate, crispy crusts, that’s only the beginning. Julia Child recommended using it in crepe batter in The Way to Cook at Amazon as a way to eliminate the rest time, since Wondra doesn’t need time to hydrate. In The Baking Bible at Amazon, Rose Levy Beranbaum uses it to create sponge and angel food cakes, since Wondra yields a tender crumb.

Pastry Flour

Ground from soft red winter or soft white wheats, pastry flour occupies a happy place in between all-purpose and cake flour. Its mid-level protein content (8 to 9%) strikes the right balance in baked goods and pastries that call for structure, flakiness, and tenderness, like cookies, danishes, and tart shells. Although primarily used by professional bakers, Bob’s Red Mill and King Arthur Flour make pastry flours that are available to home bakers. If you’re new to pastry flour and are looking for a place to start baking with it, I recommend exploring Bob’s Red Mill and King Arthur Flour’s recipe databases, which you can find here and here.

Self-Rising Flour

Self-rising flour arrived in the US from England in 1849 but rose to prominence in Southern kitchens as a result of the founding of the White Lily brand in Tennessee in 1883. In the US, self-rising flour is traditionally made from low-protein wheat grown in the South, which is likely why biscuits emerged as a Southern food staple; the ideal wheat was readily available for making those light, fluffy biscuits. What sets it apart from all-purpose flour is that baking powder (a leavening agent) and salt (a gluten strengthener) are pre-mixed in. Be aware that this flour has a shorter shelf life—the baking powder becomes less effective over time—and should be used within six months of purchase.

Cake Flour

Cake flour is milled from the innermost part of the endosperm of soft wheat. It has a higher percentage of starch and the least amount of protein (7-8%) when compared with other wheat flours, which keeps cakes delicate. You can buy both unbleached and bleached cake flour, but remember that the process of chlorination improves the baking properties of soft wheat flour by weakening gluten and lowering pH. Bleached cake flour churns out cakes that are moist and light as it’s capable of holding more sugar, butter, and additions such as nuts, fruit, or chocolate; unbleached alternatives, on the other hand, will often fall flat. We call for bleached cake flour exclusively in angel food cake, pumpkin cake, strawberry cake, and blackberry cake.

Our favorite brands are Swans Down and Softasilk, the most commonly available chlorinated cake flours. Note that although cutting all-purpose flour with cornstarch is a widely used substitute for cake flour, it may not provide the best results. The addition of cornstarch can soak up moisture in the batter, producing an angel food cake, for example, that bakes up heavy and dense.

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