The Process of converting flour from wheat in roller milling is to crush the grain between a series of fluted metal rollers using a reduction process; the fine flour particles are shifted out at each pass, returning to the next set of rollers. The rollers mills enable greater quantities of white flour to be made at high speed.
Unless run at slow speed, the friction of roller milling can cause the resulting meal to become very hot, which can lead to the damage of some nutrients. The bran produced in this method of milling is jagged in shape & often scarred with fine lines from the roller. The sousing nature of the flutes also damages the starch, which can help the speed at which the flour reacts during the bread making process.
As roller milling is a series of crushing and sieving actions, it is ideal for making clean white flour. To make whole meal flour at roller mill, it is necessary to collect all the resulting meal from each set of rolls and then mix it back together again when it has all been milled.