I used to think recipes calling for bread flour were being pretentious, like the recipes that specify Kosher salt, or fresh-ground black pepper. Then I started using Kosher salt and fresh-ground black pepper and realized, “Hey, you know what? Some of this stuff makes a difference.”
So I read up on what makes the different flours different, and it sounded pretty important. I finally tried it when I made rye bread for St. Paddy’s Day. I was really impressed, but I hadn’t made rye before so I didn’t know just how impressed I should be.
Then I made pizza dough.
I was amazed at the difference. But someone left a comment telling me that using bread flour was a “crutch”. I got a little ticked off.
Rather than go through that again, I figured I should go ahead and explain the difference. It’s all about the gluten.
Gluten
Gluten is a protein in flour. It forms long, twisted chains. These chains tangle up with each other and trap bubbles of gas released by the yeast. That’s why we put yeast in bread.
But for that to work, you need to knead the dough. Think of a bag of rubber bands. If you dump them out on the counter, you can grab one and it will just come out. But add a little something sticky — like a few drops of syrup — then roll the rubber bands back and forth under your hands. Now they’re all tangled up and ready to capture bubbles of yeast gas.
Knead too much, though, and the rubber bands will get all tangled up into a tough ball of eww. Same thing happens if you knead bread dough too much.
Bread flour
Good bread is light and fluffy. Which means you want lots of big bubbles. Bread flour comes from strains of wheat that have lots of gluten. It’s perfect for bread, pizza dough, pretty much anything made with yeast.
Cake flour
Cake is supposed to have a very tight, crumbly texture. You don’t want chewy, you want it to fall apart with a light touch. You don’t use yeast for the rise, you use baking powder or baking soda. They act much faster, and rise while the batter is baking, so you don’t need the structure of gluten to keep the gases from escaping. So cake flour is made from wheat with much less gluten.
NOTE: Some pizza makers swear by low gluten flour for their crust. Please don’t ask me to get into that discussion. Pizza people are almost as crazy as chili people.
All-purpose flour
You don’t know what you’re going to make next: bread, cake, pizza, biscuits. You can get something that’s not great for bread, but it will work; not great for cake, but it will work.
Obviously bread will be better made with bread flour, and cake will be better with cake flour. But you can make all-purpose flour better for bread by adding some vital wheat gluten. That’s right, if you want high gluten flour but you’ve got all-purpose, you can get a box of just gluten and add a few teaspoons.
For cake … you’re going to need cake flour.
Whole wheat flour
White flour has the bran, the papery outer layer, stripped off before it is ground. Whole wheat flour is made from the whole wheat berry. So by volume there is more insoluble fiber and less gluten than the white version of the same strain of wheat.
Also, the bran has sharp edges that tend to cut into the strands of gluten. This prevents the gluten from capturing as much yeast gas, which means not as much rising. This is why whole wheat breads tend to be heavier and denser, and many recipes call for part whole wheat, part bread flour.