Two interesting facts about gluten and sourdough. One, gluten is vital in making sourdough and two, sourdough has less gluten that most other wheat items.
People seem to view gluten as a light switch. Food either has gluten or it does not. That is not the case. Gluten is more like a light dimmer. Some foods have more of it than others. Sourdough is on the lower side of that scale.
Gluten forms when water and flour mix together causing Glutenin and Gliadin to bind together creating a web-like structure called gluten. Yeah gluten does not even exist on its own, it is a byproduct of flour getting wet.
Gluten adds chewiness and elasticity to the finished product. But most importantly the weblike structure of gluten catches the CO2 released by the feeding yeast. This helps the bread to rise like a hot air balloon.
Why does sourdough contain less gluten than other breads? Come back next week and I will explain.