Oats do not naturally contain gluten, but can become contaminated with other gluten-containing grains – like wheat, barley, rye and triticale.
The contamination may come from rotating grain crops on the same land as well as from harvesting, transporting, storing and merchandising.
The US federal government stipulates that, to carry the gluten-free claim, a product must contain a maximum of 20 ppm of gluten.
The patent (No. US 20180236453 A1 filed) details a mechanical system of achieving oat grains with gluten levels below 20 parts per million (ppm) and, more preferably, below 10 ppm.
The Minneapolis-based company’s patent outlines a series of mechanical operations that differ from traditional procedures to avoid contamination.
It has devised a series of operations – or a combination of series and parallel operations – to ensure cross-contamination is kept to a minimum, including width grading, multiple length grading steps and a potential debearding step.
The resulting oats may be used in gluten-free oat food products, including cereal and granola.
The company was forced to recall its gluten-free Cheerios and Honey Nut Cheerios in 2016, following wheat contamination. The recall affected an estimated 1.8 million boxes.
In 2014, General Mills filed three international patents for ready-to-bake gluten-free dough for pies, cookies and pizzas.
The gluten-free flour mixtures are made up of rice, millet and sorghum flours, as well as potato, corn and tapioca starch.
‘There is demand for ready-to-bake gluten-free products that can go directly from the refrigerator to the oven or other associated baking appliance,’ the company said at the time.