Gluten is a specific type of protein, but one you won't find in meat or eggs. Instead gluten is found primarily in wheat, rye, and barley. Going gluten-free means avoiding these grains. A gluten-free diet is essential for most people with gluten allergies or celiac disease, a condition which causes intestinal damage when gluten is eaten.
In our kitchen, almond flour is used to substitute normal pastry flour.