A General Mills, Inc. patent application on a method and system designed to establish gluten-free oats was published July 21. Various mechanical differentiation operations on a combination of grains, including oat grains and gluten-containing grains, allow the oat grains to have gluten levels below 20 parts per million (p.p.m.), preferably 10 p.p.m.

The gluten-free oats then may be used in a range of gluten-free oat food products, including cereal and granola products, according to the patent US 2016/0207048 A1. U.S. federal government rules require products labeled as gluten-free to have a maximum gluten level of 20 p.p.m.

Various mechanical differentiation operations in the patent include width grading steps, multiple length grading steps, aspirating steps and a potential de-bearding step. Using mechanical separation techniques may be effective at a low cost. The patent does not include optical systems, which generally employ multiple cameras and are associated with higher costs.

While oats do not contain gluten, oats cultivated in North America, Europe and other parts of the world commonly are contaminated by gluten-containing grains such as wheat, barley, rye and triticale, according to the General Mills patent. The contamination may come from rotating grain crops on the same land as well as from harvesting, transporting, storing and merchandising.

General Mills experienced problems with wheat contamination of gluten-free products last year. The company recalled several days of production of gluten-free Cheerios and Honey Nut Cheerios at its Lodi, Calif., plant. The recall affected an estimated 1.8 million boxes.