Why bread rises: yeast only inflates the bubbles your kneading put there

30seconds
Yeast doesn't blow bubbles into dough. It only inflates the ones your kneading already folded in.
That means the number of bubbles is fixed early, and the yeast just decides how big each gets: the same gas shared between a few bubbles makes tunnels, shared between thousands makes a fine crumb.
Knead a virtual dough, proof it at different temperatures and bake it to see why a rise isn't the same as a good loaf.
Deep dive · 4 min
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