Contrary to what you might expect, corn gluten meal does not — unless contaminated — contain any gluten at all. When corn or maize products like corn syrup are processed, corn gluten meal is one of the by-products. In your pup's food, it plays at least two main roles — however, they are not necessarily about nutrition.
First, corn gluten meal helps kibble to stay in shape: in a way, it’s a ‘binder’. Second, it does contain around 60 percent protein, so it increases the overall protein content of your pup’s dinner. It is essentially cheaper than meat, but of course, we prefer to see meat in a dog food instead of corn gluten meal. Most sources agree that the degree to which these corn gluten meal proteins can be absorbed by your dog is limited. In general, it is considered a filler ingredient.