What is gluten?

Gluten is the colloquial name for the prolamin proteins gliadin and glutenin, found in wheat and triticale, hordein proteins found in barley, and secalin proteins found in rye. When these protein are mixed with water, they form a highly stretchy matrix, which allows for the production of foods like bread and noodles. The gliadin protein is especially problematic for people with celiac disease, because it cannot be fully digested by the stomach or by enzymes in the digestive tract.

In this article, we’ll explore the history of wheat, barley, and rye production, examine the properties of gluten, and explain which specific part of the gluten protein causes reactions for people with celiac disase. If you haven’t already, it’s worth checking out our Just Diagnosed article for a quick guide to help understand which foods contain gluten.

Gluten Properties and Uses

If you did a lot of baking before being diagnosed with celiac disease or a gluten allergy, you’re probably used to recipes telling you not to ‘overdevelop the gluten’ by overmixing. With gluten free baking this will never be a problem!

Gluten adds a stretchy quality to doughs that helps increase rise, chewiness, fluffiness, adds an airy structure, and helps to create layers in foods like puff pastry and phyllo dough. Bread rises more because air is more easily trapped, and noodles and crusts can be easily stretched when gluten is developed.

Vital wheat gluten is the isolated gluten protein that’s obtained by separating the wheat starch from the wheat protein. This is dried and added to some health foods to increase protein content. It’s also sold in cubes as a meat alternative that’s especially popular in China. The dried version of gluten is called fu/ofu (麩, お麩). In the west, many vegan meat substitutes, like seitan, are made from wheat gluten because it replicates the chewy texture of meat well and provides some protein. It’s also pretty flavorless, so it adapts to many recipes well.

History of Wheat, Barley, and Rye Production

Triticeae is the name of the botanical family that includes wheat, barley, rye, and other gluten-containing grains. Oats are in a sister family, but they are gluten free when processed safely, although a small amount of people also react to the proteins found in oats. These wild grains were domesticated by humans over 12,000 years ago. Bread and beer may have even motivated the switch to agriculture. So gluten has been a part of human history for a long, long time. Of course, the versions of these grains that people consume today are pretty different than their ancestors. Modern versions often contain less fiber, protein, vitamins, and minerals than their ancient grain equivalent, because the varieties we consume nowadays were bred for higher yields and lower crop costs, rather than nutrition. While soil depletion and changes in crop production environments can also contribute to changes in nutrient levels, this development is a bit alarming.

Although the overall protein content has decreased, the specific protein epitopes responsible for celiac disease triggers have actually increased in modern versions of wheat. This has even been suggested by various studies as a reason for the increase in celiac disease and gluten intolerance over the last 50 years. The increase of these epitopes may have been on purpose, because wheat breeders have worked hard to please their customers by increasing gluten content to produce fluffier breads and chewier noodles. Nowadays, gluten makes up 75–85% of the total protein in bread wheat. None if this is to say that ancient varieties of gluten-containing grains are safe for celiacs! They still contain gluten, as does traditional sourdough, and should be avoided.

It’s a bit frustrating to learn that the modifications of these grains may have increased the likelihood of triggering celiac disease or gluten intolerance. But it’s worth noting that there are projects experimenting with using gene editing to make gluten free wheat varietals, which is really exciting. In the meantime, there are many gluten free ancient grains to try, including teff, amaranth, job’s tears, millet, buckwheat, and sorghum.

Celiac Disease, Wheat Allergy, or Non-Celiac Gluten Sensitivity

If you have celiac disease, a wheat allergy, or non-celiac gluten sensitivity, the immune response will be slightly different when wheat is consumed, although the treatment is the same: don’t eat gluten.

The markers that indicate celiac disease are IgA (IgG) anti-tTG, IgA(IgG) anti-endomysium (anti-EMA), as well as anti-deamidated gliadin peptide antibodies. For wheat allergies, markers include the wheat-specific IgE, specific IgE for ω-5 gliadin, and the specific IgE for non-specific lipid transfer proteins. Non-celiac gluten sensitivity markers may (but not always) include IgG antigliadin antibodies. Each are diagnosed via blood test and possible intestinal biopsy. For more information about these markers and their affects, see this article.