Wheat Milling

Before wheat milling into flour, it must first be cleaned and conditioned to remove foreign material and poor quality or infested kernels. Cleaning is done with an assortment of machines that utilize air currents, magnets and screens to separate the wheat from the chaff- and from other undesirable contaminants. Kernel size, shape, density, dimension and friability under impact are all qualities that can be exploited to effect separation in wheat milling.

Conditioning is the adjustment of the moisture level of the grain to facilitate maximum separation of bran from endosperm. For most wheat milling systems, wheat is conditioned to approximately 16% moisture. An optimum toughness of bran and "mellowness" of endosperm is the goal. The bran should flatten into large flakes when passing between the break rolls in the wheat milling process. If the wheat is too dry and brittle, the bran wilt be ground rather than flaked and will be difficult, if not impossible, to separate completely from the endosperm, resulting in a relatively dark flour with a high ash content. If the wheat is too wet, the endosperm will adhere to the bran, reducing the yield of flour.