|
Edited on Fri Feb-20-09 12:54 AM by housewolf
Bread flour has the most, then KA's AP, then everybody else's AP, then White Lily and other southern flours, and cake flour has the least.
There are several types of wheat grown in the US - red hard wheat flour, white hard winter wheat, and soft spring wheat. Hard winter wheat has the strongest protein, and is generally used in bread flours. Most bread flours are a mix of hard winter wheat and soft wheat, and the mills blend them to maintain a consistency of product at about a 13% protein content. KA's AP is hard winter wheat (at about 11.5% protein content), higher protein than other brands of AP flour that blend hard and soft wheats to obtain about 10% protein content, and vary by brand and by region. Cake flour is always bleached and a soft wheat flour, with about 6 - 8% protein content and the bleaching acidifies the flour somewhat. Southern flours such as White Lily are soft red winter wheat and are about 8% - 10% protein. Pastry flour is about 9-10% protein soft wheat. Then there are hard wheat specialty bagel flours that are even higher protein than bread flour to create those wonderfully chewy bagels.
Now, you might ask, what does the protein content of flour have to do with anything? And actually, when it comes to breadbaking, the answer is... not everything, but quite a bit! The higher the protein content, the stronger gluten strands can develop. The stronger gluten, the higher the dough can rise and the more "tolerant" it is - meaning that dough can hold a maximum rise for a while before falling back.
The lower the protein content, the more tender, less chewy a product will be. That's why the best cakes are made from the lower-protein cake flour, and soft flours like White Lily make the best, most tender biscuits and pie crust.
Higher protein flours also absorb more water than lower protein flours do, which is one reason why you sometimes need more water when making a recipe with bread flour than you do when making the same recipe with all-purpose flour.
For shortbread, using a higher-protein flour like KA's AP will cause a stronger gluten formation, creating a more "tough" cookie, while using cake flour would create a weaker structure, cause it to crumble. That's why recipes for chewy chocolate chip cookies call for bread flour, while replacing a few tablespoons of AP flour with cake flour will give you a more tender cookie (and possibly a bit puffier).
:hi:
|