Why are rolled oats processed before they are cooked as porridge?

Rolled oats are processed before being cooked as porridge primarily to reduce their required cooking time and to ensure the stability of the grain.

The processing involves steaming the oat groats (dehulled seeds) and then passing them between rollers to flatten them. This physical alteration increases the surface area of the grain, which significantly shortens the time needed to prepare them as oatmeal.

Additionally, processing is essential for the quality and shelf life of the product. Because oats have a high fat content, they are prone to developing rancidity due to the activity of the enzyme lipase, which can create an unpleasant soapy taste. A brief steam treatment during processing destroys this enzyme activity, thereby stabilizing the grain for human consumption.12