Dr. John
I bake gluten free breads and pastries, the doughs of which usually have hydration ratios over 100% The steam created in the oven by this much moisture is where the "rise" comes from, as there is no CO2. But getting rid of the excess moisture, so the finished product is not soggy, is a problem. These perforated mats do the job very well, as they are "vented" on all sides. I have over 12 of them, and use them exclusively for my gluten free baking.
By Dr. John, CT on January 17, 2015