The Chemistry of Flour

Basic Introduction

The biggest difference between the various kinds of flour lies in the protein content. This affects how the flours absorb water - the same amount of water in a cake flour could lead to runny, more watery dough while it could lead to a more structured, firm dough with bread flour. Protein content also plays a large role in the development of gluten, which is responsible for the structure, rigidity, and texture of the intended product.

The Different Kinds of Flour

• All-purpose flour: As its name suggests, this is easily the most versatile kind of flour on the market. Its average protein content varies by brand and ranges from 10-11.7%, so it produces enough gluten to give sandwich bread decent structure without being too wholesome. Bleached floud tends to be bland and flat in flavor.

• Cake Flour: This has a lower protein content than the all-purpose flour and averages 6-8% and therefore has much less gluten than all-purpose, which accounts for its finer, delicate crumbs. Most are bleached, which changes the starches in the flour so that it can absorb more water and fat. (1 cup of cake flour is equal to 2 tablespoons of corn starch and 7/8 cups of all-purpose flour.

• Bread flour: Bread flour has a relatively high protein content with averages from 12-14%. This results in a very high gluten development, giving artisanal/rustic breads their characteristic strong and chewy structure. This is often far too strong sandwich bread.

• Whole-wheat flour: This is made from all 3 parts of the wheat kernel (INSERT LINK)- the endosperm, the fiber-rich bran, and the vitamin-packed germ. These make it more nutritious, flavorful, and dense. Breads baked with whole-wheat flour tend to be heavy, hearty, and sour-tasting.

• Specialty Flours: There are a few specialty flours that the average chef will not encounter in their everyday lives and tend to be more useful to the professional bakers. These include:

• Pastry Flour: This flour is often used for pastries and contains a protein content between the all-purpose flour and the cake flour.

• Self-Rising Flour: This contains a leavener for convenience.