The harvested oats are delivered by truck to the mill where they are stored in grain silos. The first cleaning stage removes stalks, dust and other impurities. The next cleaning stage uses sensitive machinery to remove all material that are not oats.
Warm air is drawn up through a sealed chamber.
This gives McCann's oats its distinctive nutty flavour. Before moving to the hulling stage, small undersize oats are removed by a size separator. Unlike wheat, the outer casing or hull of the oat grain is inedible and must be removed. As this cannot be done by normal threshing, special machinery is used in the factory to strip off the husk. These can be packed and sold at this stage.