The term ‘soft’ and ‘hard’ as applied to wheat are descriptions of the texture of the wheat kernel. Their textures are also appropriate to their wheat class designation.
Hard flour, or "bread" flour, is high in gluten and so forms certain toughness which holds its shape well once baked.
Hard wheat flour may be milled from either winter or spring wheat varieties.
Those with highest protein content, characterized by their capacity to develop the strongest gluten, are used in commercial bread production where dough must withstand the rigors of machine handling.
Soft wheat differs from hard wheat in kernel softness, a basic genetic characteristics that is directly inherited.
Soft 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.
The finer particle size and lower protein of soft wheat flour gives the soft and elastic bite and smooth surface desired for Japanese white salted noodles.
One the other hand, the higher protein content of hard wheat flour gives the springiness and firmness desired for yellow alkaline noodles.
Wheat flour: hard and soft
