Bread Flour vs All-Purpose Flour: What the Protein Number Changes
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Time to read 6 min
Flour Guide
Where Bread Flour and
All-Purpose Flour Part Ways
One measurement separates the two flours, and it is printed on the bag. Bread flour generally runs 12% to 14% protein. All-purpose generally runs 9% to 12%. How the dough handles, how much water it takes and how the crumb comes out all follow from that gap.
Bread flour and all-purpose flour are separated by protein content. Bread flour generally falls between 12% and 14%, while all-purpose sits lower, between 9% and 12%. Every other difference between the two, the feel of the dough, the water it absorbs, the chew in the finished product, traces back to that one number.
A few percentage points sounds small on paper. In a mixer it shows up as dough behavior, and how much it shows depends on what you are making. A high hydration hearth loaf puts the gap on display. A butter heavy coffee cake shows far less of it.
Protein Content Is the Difference Between the Two Flours
Wheat flour carries two proteins, glutenin and gliadin. Add water and mix, and they link up into gluten, the elastic network that holds a dough together and traps the gas that fermentation produces. More protein in the flour means more of that network can form.
Bread flour is generally milled from hard wheat, which carries more protein. All-purpose is commonly a blend of hard and soft wheat, which lands it in the middle of the range and gives it the spread of uses its name describes.
That middle position is the design. All-purpose carries enough protein to hold a sandwich loaf together and little enough to leave a cake tender.
What Bread Flour Does in a Dough
Bread flour builds a stronger, stretchier gluten network than all-purpose does. A dough made with it holds more gas through the proof, which reads as more rise and a more open crumb, and it eats chewier.
It also takes on more water. Those proteins absorb more liquid than the proteins in all-purpose, so a formula written at high hydration stays workable on the bench instead of going slack and sticky.
Bagels, pizza dough, baguettes, hearth loaves and pretzels all lean on that strength. Enriched doughs can call for it too, since fat coats the flour and slows gluten development, which is why challah and similar formulas sometimes start with a stronger flour to finish with enough structure.
In a commercial catalog the step above bread flour is high gluten flour, which sits higher again on protein, often around 13% and up, and runs through bagel and pizza production.
Where All-Purpose Flour Fits in a Bakery
All-purpose flour covers a wide range of products on a bakery bench, which is where the name comes from. Cookies, muffins, pancakes, quick breads, pie dough, biscuits, cakes and sandwich loaves all sit inside its range.
Plenty of yeast raised formulas are written for it on purpose. Softer breads and rolls, where a tender crumb matters more than chew, often read better on all-purpose flour than on a stronger flour.
The other side of that is where gluten works against the product. Cookies, cakes and biscuits are meant to be tender, and a stronger flour pushes them toward firm and chewy.
What the difference comes down to
Protein sets how much gluten can form. Gluten sets structure, chew and how much water a dough will take. Use the flour the formula was built around, and when you change it, change the hydration and the mixing along with it.
Bread Flour and All-Purpose Flour Side by Side
| Question | Bread Flour | All-Purpose Flour |
|---|---|---|
| Typical protein | 12% to 14% | 9% to 12% |
| Wheat behind it | Generally hard wheat | Commonly a blend of hard and soft wheat |
| Gluten network | Stronger and more elastic | Moderate |
| Water absorption | Takes on more liquid | Takes on less, so high hydration doughs run slacker |
| Crumb and bite | More rise, more open crumb, chewier | Softer and more tender, with a tighter crumb |
| Where it goes | Bagels, pizza, baguettes, hearth loaves, pretzels | Cookies, cakes, muffins, pie dough, quick breads, soft rolls |
Read the Protein Number Before the Flour Name
Bread flour and all-purpose flour are category names rather than regulated specifications. The percentage behind each one varies by mill, by wheat crop and by product line, and the two ranges overlap at the edges. An all-purpose flour near the top of its range can land close to a bread flour near the bottom of its own.
Commercial flour brings more names into the mix. Patent, clear, high gluten, bread and all-purpose all appear in the same catalog, and the trade name tells you less than the protein figure on the spec.
So read the number. When a mill changes or a bag swaps to another brand, check it again, because a formula tuned to one protein level will behave differently at another.
Before changing flours in production: run a test batch at the hydration and mixing time you plan to use. A flour that absorbs water differently will also handle, proof and bake differently, and the bench is a cheaper place to find that out than a full production run.
Substituting One Flour for the Other
Swapping one flour for the other works, with adjustments. The two take different amounts of water and different handling, so a straight 1:1 exchange moves a formula away from the point it was tuned to.
Going from all-purpose to bread flour in a bread formula, the dough will usually take a little more water. Going the other direction, pull the water back slightly and mix more gently and for less time, since the weaker network tears sooner.
The results move too. All-purpose in place of bread flour tends toward a tighter crumb and less chew, with a slacker, stickier dough at the same hydration. Bread flour in place of all-purpose in cookies, cakes or biscuits firms up the texture.
There is a middle route. Vital wheat gluten mixed into all-purpose raises the protein of the blend, commonly at 1 to 2 teaspoons per cup, which brings the strength closer to bread flour.
How much of this you notice depends on the product. Items that get their structure from fat, sugar or chemical leavening rather than from a fermented gluten network show less of a difference between the two flours.
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Frequently Asked Questions
How Does Cake Flour or Pastry Flour Compare to Bread Flour and All-Purpose Flour?
Both sit lower on protein, generally 7% to 9%, which is what makes them suited to tender cakes and pastry instead of chewy bread. Cake flour is typically milled finer than all-purpose. Line the four up and the order runs cake and pastry at the bottom, all-purpose in the middle, bread flour at the top.
Can Vital Wheat Gluten Turn All-Purpose Flour Into Bread Flour?
Adding vital wheat gluten raises the protein of the blend, commonly at 1 to 2 teaspoons per cup of all-purpose flour, and the strength comes up with it. The wheat and the milling underneath stay what they were. Treat the result as close rather than identical, and test it before it carries a production batch.
Why Does the Protein Percentage Differ Between Two Bags of Bread Flour?
Wheat is a crop. Protein moves with the growing season, the variety and the blend a mill builds, and the flour names are categories rather than fixed specifications. The figure on the spec sheet is the one to work from.
Does Bread Flour Change How Much Water a Dough Needs?
Higher protein flour absorbs more liquid, so a formula moved onto bread flour usually has room for more water than it had before. Add it in small increments and judge the dough by feel rather than jumping to a new hydration number in one step.
Which Flour Do Enriched Doughs Like Challah and Brioche Use?
Fat slows gluten development, which is why a rich dough can start with a stronger flour and still bake up tender. Many enriched formulas are written around bread flour for that reason, and many others are written around all-purpose. The formula settles it, and the fat and sugar levels in that formula are doing as much work as the flour is.
Can All-Purpose Flour Be Used for Sourdough?
Plenty of sourdough formulas are written for all-purpose and work as written. At high hydration the dough runs slacker and wants a gentler hand through shaping, and the crumb tends to come out tighter than the same loaf built on bread flour.
Stocking Both Flours in a Production Kitchen
A kitchen running both bread work and pastry work covers most of its formulas with two flour positions. All-purpose handles the tender side along with the softer yeast raised items, and bread flour, or a high gluten flour above it, handles the products that need a strong network and a long proof.
Write the flour type and its protein on the formula card next to the weight. A card that reads bread flour at 12.5% tells the next person what to pull and what to check when the mill changes, which is the practical reason for knowing the difference at all.
Baker's Authority carries flours in 5 LB and 50 LB bags for bulk and wholesale buyers, across all-purpose, bread, high gluten, pastry and whole grain.