To a baker, “gluten” is the substance in flour that, when combined with a liquid, is responsible for creating the sticky, elastic texture of raw dough. But what exactly is gluten? In simple terms, gluten is the general name for specific protein fractions (prolamins and glutelins) in wheat, barley and rye. And while other grains contain prolamins (e.g., zein in corn, sometimes referred to as “corn gluten”; orzenin in rice), these proteins are not harmful to persons with celiac disease or non-celiac gluten sensitivity.