Cake flour is a low protein flour that is made from soft winter wheat. It has a protein content of about 8% and is usually bleached, which gives it a very fine texture and a very light color. Because it has such a fine texture, cake flour should be sifted before incorporating it into a recipe to prevent clumping.
Cake flour is great for making cakes and other baked goods because it gives you a very tender result. This is because it has such a low protein content compared to other flours and less gluten forms when you mix it into a batter, producing a cake with a fine, soft, even crumb.