Core Gluten-Containing Grains
Gluten is a group of proteins found naturally in several grains. These grains and their derivatives are the most common reason a product is not gluten-free and must be strictly avoided by those with celiac disease.
Wheat and its many forms
Wheat is the most prevalent source of gluten and appears in countless food products. Beyond standard wheat flour, it is crucial to recognize its various forms, including wheat berries, durum, semolina, spelt, farro, einkorn, graham flour, Kamut® khorasan wheat, and triticale.
Barley
Barley is a gluten-containing grain used in many products, sometimes in unexpected ways. Malt, produced from barley, is used for flavoring in items like malted beverages, malt vinegar, and malt extract. Brewer's yeast, often a byproduct of beer making, can also contain gluten.
Rye
Rye is a grain containing secalin, a form of gluten, commonly used in bread and other baked goods. Triticale, a cross between wheat and rye, also contains gluten.
Hidden Sources of Gluten
Beyond obvious flour-based products, gluten can hide in many processed and packaged foods as a thickener, binder, or flavoring agent.
Additives and starches
These can include modified food starch (if wheat-based), dextrin and maltodextrin (potentially wheat-derived), yeast extract (potentially from barley), and some caramel coloring (sometimes from barley).
Sauces, condiments, and seasonings
Traditional soy sauce, often containing wheat, is a common hidden source; gluten-free alternatives like tamari or coconut aminos are recommended. Teriyaki sauce often contains soy sauce and is typically not gluten-free unless specified. Malt vinegar, derived from barley, is also not gluten-free. Gravy and stuffing mixes, as well as many bouillon cubes, often contain gluten as a thickener or stabilizer.
Meats and meat substitutes
Processed meats such as hot dogs and sausages may contain gluten as a filler. Imitation crab meat often uses wheat as a binder. Seitan is a vegetarian substitute made from wheat gluten.
Drinks
Most traditional beers, ales, and lagers are made from gluten-containing grains. Any beverage containing malt is not gluten-free, with the exception of those specifically brewed and labeled as such.
Comparison of Common Gluten vs. Gluten-Free Alternatives
To help navigate shopping, here is a quick guide comparing common gluten-containing items with their safe, gluten-free counterparts.
| Product Category | Not Gluten-Free Version | Gluten-Free Alternative |
|---|---|---|
| Flour | Wheat flour, spelt flour, rye flour | Rice flour, almond flour, tapioca flour, buckwheat flour, coconut flour |
| Soy Sauce | Traditional soy sauce | Tamari (specifically labeled GF), coconut aminos |
| Thickeners | Wheat flour (for sauces, gravies) | Cornstarch, arrowroot powder, potato starch, xanthan gum |
| Grains | Barley, couscous, bulgur, farro | Quinoa, rice, millet, amaranth, teff |
| Vinegar | Malt vinegar | Distilled white vinegar, apple cider vinegar, balsamic vinegar |
| Condiments | Some mustards, marinades, salad dressings (check label!) | Certified GF mustards, most olive oil and vinegar, homemade dressings |
| Processed Meat | Hot dogs, sausages with fillers | 100% pure meat products (always check seasoning) |
| Beer | Most traditional beers, lagers, ales | Certified GF beers, wine, cider |
The Problem of Cross-Contamination
Even if a product's ingredients are naturally gluten-free, it can become contaminated with gluten during processing or preparation, which is a significant risk for those with celiac disease.
Manufacturing and processing
Cross-contamination can occur through shared equipment used for both gluten-free and gluten-containing grains or from airborne flour in processing facilities.
Restaurants and home kitchens
Shared deep fryers, cooking surfaces, and even using the same knife for gluten and gluten-free items can lead to cross-contamination.
How to Read a Label for Gluten
Becoming a savvy label reader is essential for avoiding accidental gluten intake.
The 'Certified Gluten-Free' label
This label indicates the product contains less than 20 ppm of gluten, meeting FDA standards.
The ingredients list
Scan for wheat, barley, rye, and their derivatives like malt or spelt. While wheat is an allergen that must be declared, barley and rye may not always be explicitly listed.
The 'Contains' statement
This statement will declare wheat if present, but it might not list barley or rye as they are not among the top allergens required to be declared.
Conclusion
Navigating a gluten-free diet involves understanding what ingredients make something not gluten-free beyond just obvious sources. Recognizing core grains, identifying hidden gluten in processed foods, and being aware of cross-contamination risks are vital for those managing celiac disease or gluten sensitivity. Diligent label reading, prioritizing certified gluten-free products, and asking questions when dining out are key to maintaining a safe diet.
For more detailed information on celiac disease and a comprehensive list of gluten sources, consult the Celiac Disease Foundation.
Note: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare professional or registered dietitian for personalized dietary guidance.
