Oats are probably the most controversial of the grains because in and of themselves they are not considered gluten free. But they can be subject to what is known as cross contamination. This occurs when one grain comes into contact with another. You may want to check out Are Oats Gluten Free for more. And this can happen from several sources, i.e., rotation of crops, transportation mechanisms, and cooking environments.
Many farmers that farm oats will often include in the rotation, other grains such as wheat, barley, rye and a host of others. It should be noted that the comparison here is with the grains that typically contain gluten because that is where the problem lies. Advanced farming techniques have taught us that rotating crops yields better results but this rotation often happens at a cost, i.e., there are residual gluten sources from the wheat, barley, or rye when it’s oats turn to grow.
Many grains are transported by rail and these cars are seldom completely sanitized to remove products that may have been previously transported. This means that if it is oats turn to be transported and any previous transport was for any of those other grains, contamination is very likely.
Recently, Dominoes pizza announced that they made a gluten free pizza. But it was investigated that these pizzas were made on the same surface as a regular pizza. I am not aware if changes have been made since that report occurred but one must always be cognizant of the possibility of cross contamination from cooking environments.
So does all of this talk about contamination mean one should stay away from oats if they are on a special gluten free diet? Care is needed but oats can be consumed. Processes have improved greatly and there are several producers that are getting certified by the Gluten Free Certification Organization as being gluten free. More will follow as the popularity of the diet continues to grow.
In general, if a person has an intolerance to gluten but they do not have celiac disease then they can probably get away with a very tiny amount of it that may have trickled in. Someone with celiac disease however, can tolerate so little gluten that the risk is probably not worth it. This is a big shame too as oats often are a great source of fiber. But remember that beans are an even better source of fiber and beans do not contain gluten.Are Oats Gluten Free