Wheat kernels contain three parts: the outer coating known as bran, the germ portion that contains the plant embryo and the endosperm that comprises up to 80 percent of the kernel. Wheat is milled to separate these components and recombine them in various ways to create an array of flours. Semolina flour is manufactured by coarsely grinding the endosperm of a type of hard spring wheat known as durum. Semolina flour is considered a high-gluten product.
Durum wheat is a tough golden grain and the semolina flour derived from this grain is hard and granular, with a consistency similar to that of sugar. Semolina flour is not a good choice for general bread baking, but is occasionally used in specialty breads. More commonly, semolina flour is used to produce couscous dishes or pasta products, including macaroni, spaghetti, vermicelli and lasagna noodles.
All varieties of wheat produce a form of plant storage protein, or gluten, known as gliadin. Barley manufactures a storage protein called hordein and rye plants contain secalin gluten. These three forms of gluten trigger an autoimmune disorder known as celiac disease in susceptible individuals. The Celiac Sprue Association warns people with celiac disease to avoid semolina flour.
If you have celiac disease, your body identifies the gluten in semolina flour as a foreign body and launches an attack that damages the villi, or small projections inside the lining of your small intestine. The villi become less effective at absorbing nutrients and ongoing damage to the intestinal wall allows toxins to get into your blood stream. As a result, you can become malnourished and develop chronic diseases, such as osteoporosis, arthritis and skin problems. Symptoms of celiac disease include abdominal pain, bloating and diarrhea, as well as fatigue, joint pain, anxiety and tingling in your hands and feet. A gluten-free diet is the only proven treatment for celiac disease.
Flour made from any type of rice -- white, brown and sweet -- makes a good gluten-free substitute for semolina flour. Other options include potato, buckwheat, sorghum, bean and quinoa flours. Each flour substitute has a different impact on the taste and texture of the food being prepared. Mixing several flours together and adding tapioca or potato starch creates a better product. Gluten helps bind ingredients and creates elasticity that allows dough to rise, so you may need to add other binding and leavening ingredients, such as eggs, baking powder and xanthan gum.
It's easy for particles of flour to travel through the air or on the cook's apron, hands and utensils. Then gluten-containing flour ends up in what should be a gluten-free product. The label won't tell you if products are cross-contaminated; you may have to ask whether the food was prepared in proximity to gluten-containing foods. Keep gluten-free flours in a separate area of your kitchen or pantry, and clean food preparation surfaces and baking pans thoroughly to ensure they’re gluten free.