Does anyone know why my bread falls while baking?
the dough is over proofed so when it hits the heat it falls, rather than being 90% proofed and it springs like it should.
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For clarity's sake,after being mixed, a dough will :
1.ferment or bulk ferment (or first rise) to double or almost double,
2.be knocked down and shaped-maybe even put in a pan,
3.proofed (second rise or rise in pan)-this is where the finger poke test comes in (telling when the dough is properly proofed by feel and behaviour when the dough is poked with a finger)
4.then be baked.
dabrowman is probably absolutely correct. When dough is overproofed, the gluten strands that trap the bubbles is so overstretched and weak that it can't hold the bubbleas it expands in the heat of the oven and so the bubbles pop and the loaf collapses. If the loaf is proofed properly, the dough will rise and the gluten is relaxed enough to expand in the heat of the oven but strong enough to contain the bubbles of gas until the dough is finally "set" and holds everything in place.