What is happening on a molecular level when kneading dough with yeast in it?

Question

I just made pita bread and had to knead it for 10 minutes then let it sit 10 minutes. When I came back to it after those 10 minutes it was all pillowy and soft. I’m curious what’s happening on a molecular level while kneading to make this happen.

In: Chemistry

Answer 1

Kneading dough with wheat flour in it helps it develop gluten, which is the protein that makes the dough more stretchy and sproingy.

Your yeast, meanwhile, is breaking down the wheat a little into sugars that it’ll use to grow, and CO2, which it spits out. That CO2 is what makes the bubbles in your bread.

If you don’t knead enough, there isn’t enough gluten formation to hold in all this CO2 that make those cool pockets. It can lead to thick, dense bread with no bubbles.