The Nima Gluten Sensor tests samples of food for gluten, a protein found in wheat, barley, and rye. The Nima Peanut Sensor tests samples of food for peanut.
You can read more details about the chemistry on our science page.
There are limitations around Nima's ability to detect gluten in all substances. For example, fermentation/hydrolization produces changes in the gluten protein, so Nima won't be able to detect hydrolyzed gluten, or gluten in fermented foods (such as soy-sauce or gluten-removed beers).
Corn, rice, and oats, while glutinous (meaning "like glue in texture") do not contain the same gluten protein found in wheat, barley, and rye that people with Celiac disease or gluten sensitivities react to, so Nima doesn't search for corn, rice, or oats in samples of food. Nima would however search for gluten contamination in those foods.
For a full list of tested foods, limitation foods and special testing recommendations, click here. You can also review the Nima Gluten Sensor Manual and Nima Peanut Sensor Manual for more information.