As defined on Wiki Answers:
Gluten is a combined protein found in grains. Glutens from different grains have different properties, and they form the majority of protein in most grains. Proteins hold other things, like starch, together and are often used as binders and thickeners in food products. The gluten in wheat gives dough its toughness, and the higher the protein (gluten) content, the more "rubbery" the dough is.
When people use the term 'gluten' or 'gluten-free,' they are almost always referring to the glutens found in the grains wheat, barley, kamut, rye, spelt, and triticale (Plus semolina, durum, and freekeh), which contain a chemical different from other grains that causes an auto-immune reaction in people with celiac disease or gluten intolerance. Such people cannot ingest glutens from these grains without suffering an auto-immune response that damages their intestines and can lead to many symptoms, including internal bleeding and cancer of the intestines.
There are also gluten or specific grain allergies, which are different from intolerances.
All our Kathleen’s and Louisiana Purchase (Dry Rice and Bean) products are gluten free, meaning they are not manufactured with any ingredients that contain wheat, barley, kamut, rye, spelt or triticale. Since we adhere to a truly “natural” ingredient deck, we have intentionally not used any “flavorings” such as “natural flavors” that may have been made using wheat glutens.
Our Louisiana Purchase Gumbo Roux does contain wheat flour. This product is manufactured in an outsourced location and when we warehouse this product, we adhere to a strict allergen policy in compliance with our HAACP approved plan.