For those who do not make bread every weekend or have an obsession with baking cakes, it is important to know the difference between all-purpose flour, pastry flour and cake flour.
First, what’s the same about all these flours is that they are all made from wheat. What makes them different is how they are milled, what kind of wheat they’re made from, and even what time of year the wheat was actually harvested. But what it really all boils down to is the protein content.
Protein content is directly related to how much gluten can be formed using that particular flour. Gluten helps create the structure and determine the texture in your final baked good. Flours with low protein contents will generate less gluten and flours with high protein content will create more.
To get the light and airy structure of cakes such as Angel Food cake, you want flour with very little protein. But to form the dense chewy structure of bread, you want flour with a lot of protein so that you can create as much gluten as possible.
- Bread Flour: 14 – 16%
- All-Purpose (AP) Flour: 10 – 12%
- Pastry Flour: 9%
- Cake Flour: 7-8%
The exact protein content varies by brand, region, and also by country. However, the name given to the flour is usually an indication of how it’s intended to be used. If you’re having trouble with a recipe written by someone in another country, try to figure out the protein content of the flour they’re using and then find your local equivalent.
Substituting flours with different protein contents can get a little tricky. For most intents and purposes, you’re safe using pastry and cake flour interchangeably. You can also always use all-purpose flour for either pastry or bread flour.
If all you have is all-purpose flour, you can approximate cake and pastry flour by adding 2 tablespoons of corn starch to a cup of AP flour. Likewise, you can bump up a flour’s protein content (and it’s gluten potential) by adding a few tablespoons of vital wheat gluten.