Q: I've come across numerous recipes over the years for different types of bread. Some have asked for bread flour and I've always substituted all-purpose. What's the difference between the two? Is using AP flour in place of bread flour causing my bread to be heavy and dense?
Sent by Anne
Editor: Bread flour has more protein content than all-purpose, which helps with gluten development. Some recipes call for it when an especially chewy and elastic crumb is desired.
You'll notice some difference in crumb and texture with breads made with each flour, but the flours can generally be substituted for one another. I tend to exclusively use AP flour, too! If anything, using bread flour will give you a heavier and denser loaf; if you're getting heavy, dense loaves with AP flour, then something else might be going on.
• What's the Difference? Cake Flour, Pastry Flour, All-Purpose Flour, and Bread Flour
Readers, what do you think about breads made with bread flour or AP flour?
Related: Bread Baking Clinic: Under-Kneading and Over-Kneading
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The chocolate chip cookies I make ask for a mix of bread and cake flours (in different amounts), and they always turn out so well I wouldn't dare mess with it, but doesn't cake flour have less protein, so adding the two together makes essentially an A/P Flour? I like to think part of the magic of the cookies is the mix of flours, the texture is amazing.
Carla, I know the recipe you're talking about. I used AP flour because I felt the same as you (namely, that they cancel each other out), and the cookies really did turn out differently. So I just stick to the two flours now. :)
As for bread flour, I already have whole wheat and cake flour in addition to AP flour, and I don't want another bag of flour under the cupboard. So...I bought a little bag of Bob's Red Mill gluten (forget the actual name, but that's basically what it is). 1 tbsp per cup is the substitute. Works great, takes up less room, and much cheaper!
I make bread every 4 or 5 days in my bread machine, and learned the hard way that AP flour is not a good substitute for bread flour. I also buy cake flour for special occasion layer cakes, and I am absolutely scrupulous in measuring ingredients or weighing them.
Note that Canadian AP flour has a higher gluten count than American AP flour, and thus can be used for bread.
"If anything, using bread flour will give you a heavier and denser loaf..." I don't agree with this statement. Better gluten formation using bread flour means that the dough will be able to support larger air pockets (from the CO2 expelled by yeast), resulting in a lighter crumb, not denser. The air pockets in AP flour break down sooner, resulting in a tighter crumb. This effect bears out both in theory and in practice. However, another thing that bears out in practice (trust me) is that either flour can result in heavy and dense bread if the gluten is not developed and aligned in the dough. The amount of surface tension in the final shaped loaf will also influence oven spring. I would suggest looking up stretch and fold techniques and dough shaping techniques to improve dough strength and structure.
In addition to the "strength" of the dough, the protein content of the flour influences the tenderness of the crumb in the baked product. Lower protein flours like cake flour result in a more tender crumb, whereas, higher protein flours like bread flour result in a more chewy crumb.