I stumbled upon a great read by Joy the Baker about the difference between the most common wheat flours used for baking. Really, it’s fascinating, but in case you’re all TL;DR, here’s the gist of it. The defining difference is the amount of protein each type of flour has. All-purpose flour hovers around 10.5% (although King Arthur’s is actually 11.7%), whole wheat flour’s protein content hovers around 14%, bread flour is 13%, cake flour comes in at 9% and self-rising flour is a lower-protein flour at about 8.5%.
So what do these silly numbers mean? You can really tell the difference in the texture of the baked good. The higher protein content of bread flour helps create more gluten and a bigger rise in yeasted breads (think of a slice of artisan bread compared to a banana bread, which is more dense). The mid-level protein in all-purpose flour makes it good for a variety of baking endeavors, hence it’s all-purposeness. Self-rising flour’s lower protein count means it’s great for creating fluffy, light biscuits (Joy includes a quick way to make your own), while whole wheat flour is great for a denser baked good with a stronger wheat flavor. (Also, did you realize that whole wheat flour can go rancid because it contains the germ of the wheat berry? Now I know why they recommend to store whole wheat flours in the freezer.)
It got me thinking, why do I use whole wheat pastry flour so much? Honestly, I owe this decision to Kathryne of Cookie+Kate, who uses whole wheat pastry flour in many of her baking recipes. She introduced it to me through her awesome honey banana bread recipe, which of course heavily influenced my favorite chocolate chip banana bread. Other than reading her thoughts about it on her blog once in a while, I never looked into the benefits and uses for this specific type of flour.
I assumed that since it felt finer between my fingers than regular whole wheat flour or even all-purpose that it would be good for lighter baked goods like cakes and muffins, but I’ve also found it fine for cookies and quickbreads. I really love the stronger flavor (and slightly better fiber count — score for healthiness a midst all the butter and sugar!) of whole wheat flour.
After reading Joy’s article, I realized that I had only assumptions to go off of why I buy and use whole wheat pastry flour. Trust me, I do go out of my way to get it, since it’s hard to find in grocery stores, and buying it at Whole Foods means it’s much more expensive.
After not very much googling, I learned my suspicions weren’t that far from the truth! Like regular cake flour, the protein content of whole wheat pastry flour is at 9%, which confirms my half-baked notion that it’s a good flour for lighter baked goods with a nice, tender crumb, like cupcakes. King Arthur Flour also says it’s fine for cookies, pie crusts and hearty cakes. I mean, I did make a mocha angel cake with whole wheat pastry flour and it turned out SUPER BOMB, so I didn’t exactly doubt myself. I just wanted to know the real reasons behind this flour’s awesomeness.
BTW, one thing whole wheat pastry flour is so NOT AWESOME for: yeasted breads. The first time I tried to make a fluffy whole wheat sandwich bread, I ignored when the recipe called for a mix of regular whole wheat flour and bread flour (mostly because I had neither), and used the small bit of all-purpose flour mixed with a higher proportion of that pastry flour. God, what an awful rock that “bread” turned out to be: super heavy and dense, dry crumb, no spring whatsoever. I cried a little actually, and only felt better 2 days later when I decided to cut it up into chocolate chip bread pudding. What can I say? I save things by adding chocolate chips to them, but still, it was a fairly hearty bread pudding. But after reading Joy’s article, it makes perfect sense, since the lower protein content makes it difficult to create gluten and properly rise. For future bread-baking trials, at least now I know.
And now you also know why I like whole wheat pastry flour and what it’s best for. You’ll continue to see it in many of my recipes, though of course, not every one of them will call for it. Happy eating!