Flour is the product obtained by grinding wheat kernels or “berries.” Flours milled from soft wheat kernels are whiter in color and finer to the touch than hard wheat flours.
Soft wheat flour is comparatively low in gluten and so results in a finer texture. Soft flour is usually divided into "cake" flour, which is the lowest in gluten, and "pastry" flour, which has slightly more gluten than cake flour.
It produces more tender products, and this is desirable for many in cakes, pastries, cookies, crackers, oriental noodles and pastries. Flour with low protein content, low ash content, and weak gluten characteristics makes good quality sponge cake.
Cake flour has a greater percentage of starch and less protein, which keeps cakes and pastries tender and delicate. Protein varies from 7 to 9 percent.
Pastry flour is milled from soft wheat, generally from soft red winter wheat. It is low in protein—typically 7–9.5 percent—and is not usually bleached. Pastry flour is ideal for cookies and many pastries.
Soft wheat flour - has a lower gluten content