Cravings of a Food Scientist

Is gluten a carbohydrate? Or maybe a fiber? Or maybe it’s just a bunch of unknown chemicals that are bad for you? Many of you have probably heard of gluten and may know a little about it, but aren’t really sure exactly what it is or why it’s viewed so negatively.

Actually, gluten is a protein that is made up of two smaller proteins: glutenin and gliadin. These two proteins combine during the mixing and kneading process to form gluten, which essentially forms the structure of the dough and any baked good. This protein is present in wheat, rye, and barley. Other forms of flour like rice flour or ancient grains do not contain gluten and are used to make premium gluten-free products. Many companies are even offering gluten-free flours or baking mixes for those who want to bake at home.

Now, if you’ve ever tried any types of gluten-free products you know they are….usually not that great. Why is that? Why is gluten so important when other flours are available?

To give you a better understanding let’s first take a look at the proteins that make up gluten. Gliadin is sticky and stretchy, while glutenin is strong and rubbery. When the two combine to make gluten, the end result is a strong dough with structure that can still stretch and extend to allow gases to become trapped in the dough and bread to rise.

Here is a sample of pure gluten that has been taken from a small dough ball. In the top photo you see the starting product, a simple dough ball of flour and water. After the dough is mixed and kneaded we allow it to rest. We then run the dough under water to wash away the starch. Starches are complex carbohydrates (many sugar molecules linked together). You can see in the bottom left photo the gluten structure webbed throughout the starch as it is washed away. Finally, we are left with a pure ball of gluten. If you were to stretch it, it would be very extensible and very strong. It would not tear easily. Give it a try at home for yourself! Try different types of flour, also.

The amount of gluten in the dough is directly related to the protein level of the flour. For example, in your pantry, bread flour has the highest amount of protein, all-purpose flour has a moderate amount, and pastry flour or cake flour has the least protein. So, how does that relate to the structure of the product? Well, just think about bread versus cake. Because there is more gluten, bread is dense and firm. On the other hand, cake is softer and more airy.  This is why it is so difficult to formulate gluten-free breads, and why it is not wise to switch one type of flour for another in recipes. Not many proteins can mimic the strong yet stretchy nature of gluten.

Wheat grains have long been a part of the human diet. Many people may believe that bread is a processed food new to the human diet, but this is not necessarily the case.  Unfortunately, a very small percent of the population has Celiac disease or a gluten sensitivity (technically non-Celiac gluten sensitivity). Celiac disease is an autoimmune disorder in which the body attacks its own digestive system in response to gluten. As the digestive system is injured, it cannot properly absorb nutrients, making this a life-threatening disease. On the other hand, a gluten intolerance or sensitivity is less defined. These people may experience gastrointestinal problems, but there is no clear reason why. It may even be a different food component causing the issue.  In addition, people may also develop wheat allergies. This is just like a regular allergy you are familiar with, such as peanuts. It can cause a rash, hives, difficulty breathing, etc.

Now that you know a little more about gluten, you can see why it can be confusing. Gluten is actually a protein similar to proteins we find in other products like meat. Those who are not suffering from Celiac or a gluten sensitivity have no reason to avoid gluten. Gluten-free products are not inherently healthier and there is little evidence that a gluten-free diet provides health benefits for those who do not need it. Remember that whole grains are an important part of your diet, as well, and by avoiding these products you may be avoiding essential nutrients.

Please keep in mind, this post is not meant to diagnose or provide medical advice. If you have symptoms involving gluten, you should talk to your doctor with questions and to find the best treatment for you.