The Process of How Oatmeal is Made

Packaged oats are a common food item today. Quick oats, steel cut, flavored, cereal bars—the list goes on. Any oat lover should know the process of how oatmeal is made to better understand this classic food staple. Food processing relies on industrial rollers for all parts of the process from cleaning to packaging.

Milling

Milling removes foreign materials and converts the oats into usable cooking material. The plant genetics, such as kernel size, can affect the milling process. The milling process occurs through the cleaning, sifting, steaming, rolling, cutting, roasting, and packaging steps that convert wild oats into packaged oatmeal.

Cleaning, Sifting, and Sorting

Oats are loaded onto trays where they’re washed under a high-intensity water spray. The oats are screened to remove foreign materials from harvesting. This cleaning and sifting pattern repeats until all large and small debris are removed. In some cases, the oats get clipped before this process. Clipping makes dehulling easier. After the cleaning process, a large separator divides the oats into different sizes. Larger oats are used for oatmeal and other food products, and they continue along the process. Smaller oats get used for animal feed.

Grading

The oats are then graded based on their size and density. Graders use width to judge oat size, and a series of perforated cylinders perform this task. The size of the oat determines which perforated cylinder they fall in. Small and medium oats fall through the first cylinder and the large oats fall through the last.

Dehulling

Humans can’t digest oat hulls. The hull must be removed to make oatmeal safe for consumption. Discs rotate at different speeds (depending on the oat size) to remove the exterior. Larger oats require slower rotations, while small oats require faster rotations. Moisture also affects the dehulling process—high moisture decreases dehulling efficiency, whereas low moisture increases it. What’s left is a mix of hulls, groats (dehulled oats and grains), hulled oats, and broken groats. This then gets aspirated to further remove hulls and small particles. Once this is done, tilted tables with bumpers rock back and forth to separate hulled and dehulled oats. The dehulled oats continue along the process, and the hulled oats go back to disc rotation for another round.

Drying

The next stage of the process is drying or kilning. Due to the fat content in oats, oats must be dried to achieve browning and desired tastes. The oats are sent to long vertical cylinders where air and steam is injected to increase temperature and moisture. While the moisture helps increase the enzyme content, it’s bad for shelf stability and can ruin the product. Radiant heating is used to remove this excess moisture. This step is important for developing the oat’s nutty flavor, and it also kills any inactive yeast or bacteria.

Rolling and Cutting

Once dried, oats run through a cutting machine where sharp knives slice them into flakes. This method produces steel-cut oats. Quick oats get rolled between cylinders. This produces a flatter, lighter flake. During this process, the hull is separated from the grain. The remaining hulled oat gets sent for roasting.

Roasting and Packaging

Hulled oats are placed in a roaster where they toast for a set time. After roasting, the oats then go to pre-printed containers for packing. A measurement system ensures the same amount of oats go in to each package. The lids of the containers are then vacuum-packed on the top. The last step in the process of how oatmeal is made is the containers get ready for shipment to a store.