from the food scientist: flour

I'm sure you've  been to the store and seen different types of flour and thought, why would I buy another type of flour when I already have all-purpose?  Well, folks, there is a difference and using the right type of flour will make your baked goods even better.  My husband is studying Food Science at BYU and he tells me lots of cool baking things, including why different flours are better for different occasions.  So, here's the scoop, in his words.

All-Purpose Flour

This your flour that is good for everything.  It can be used in cakes, pastries, breads and many other things.  What makes it all-around good is the fact that it is from wheat that has a medium amount of protein.  The protein in wheat is really what gives flour its different functionalities.

Cake Flour

Cake flour is the flour of choice for those making the good things in life; cakes, pastries, cookies and other yummy things.  It is used to make these things lighter compared to using all-purpose flour.  The flour is milled to a finer grain size so that it can absorb more fat, causing it to be distributed more evenly throughout the cake batter.  Another things that makes cake flour different is the protein content.  Because it has a lower protein content, when it is mixed in a cake batter it doesn't create a very strong structure.  This is important to give the  nice fluffy texture.  This is also why cake flour is not for making breads because they won't hold the structure you want.

Bread Flour

This is our friend Mr. Bread Flour.  It is very good for making, you guessed it, bread.  Some of the desired characteristics of bread are that it holds the leavening well and has a nice strong structure.  Bread flour has a higher protein content.  The two major proteins in wheat flour are glutenin and glyadin.  When the flour is hydrated these proteins come together to form a structure we call gluten.  Gluten is what gives breads their airy and fluffy goodness.  They provide a structure that can capture all the gas produced by the yeast and also be elastic to give it a good texture.  Since bread flour has a high protein content it is better for bread making for these very reasons.

Soy Flour

One quick note about soy flour.  Now you might think to yourself soy flour?  Why would I use soy flour?  Well soy flour has a high protein content like bread flour.  This flour when added to bread flour in a yeast bread recipe can improve the texture and capability to hold the gas produced by the yeast.  It should be used sparingly though, too much and it'll taste like soybeans.  :(

Well these are the basics on different types of flour.  If you have any questions, feel free to ask away.