The Probert Encyclopaedia of Food & Drink

FLOUR

Flour is a fine, soft powder formed by grinding or rubbing the seeds of various grasses, most usually in Britain and America wheat. Flour may be wholemeal or white, depending upon whether just the iner white part of the seed is kept, or whether the rough outer husk is also retained. Plain flour is another name for flour, distinguishing it from self-raising flour which has added baking powder to generate bubbles when the flour is cooked, which is essential for making cakes.
Research Flour