How to Hull Oats

Harvest the mature oat stalks with a hand-held sickle or a commercial mower. Leave the stalks out on the field to sun-dry for two days, before gathering them together. Roll into cubes or cylinders with a large mower-type vehicle called a baler. Move the bales to a dry storage house, where the oat straws dry for 2 weeks. After the stalks are dry they are ready for threshing.

Place the oat bales into a thresher, which is a machine that will remove the kernels from the stalk. The bundles of oats are fed into the top of the machine, which grinds the oat straw and deposits a pile of separated seed kernels at the other end. Each oat stalk should render about 30 to 40 grains.

Feed the grains through a winnowing machine. This will help to clean the grains by clipping the bottom of the oats, removing the chaff (remnants of the oat straw). Also, the winnowing process removes weevils and other insects, along with dust, debris or rocks that might have gotten mixed in during harvesting and threshing.

Roast the oats to help loosen the grains from the hulls. The hull is the inedible outer layer or husk that encases the oat seed. Roasting is often done by putting the oats into a kiln, which is calibrated to 215 degrees F. In the kiln, the oat grains steam and swell in their hulls for 2 hours, a process that loosens the husk, activates enzymes and gives them a nutty flavor.

Remove the hull of the oat grain by feeding the roasted oat grains through a huller. The cylindrical machine spins the oats around, while lightly beating them with rubber strips. The aim is to coax the roasted oat grain out of its hull, without breaking the kernels. The end result is edible oats, often referred to as rolled oats, which can be cooked and eaten whole or crushed to make oatmeal.