Rescues · TO PROOF
Huge irregular holes and a pale, tight crumb underneath.
Why it happens
Under-proofed and under-developed. The gas concentrated in a few weak points rather than distributing through a fine network.
Recovering it
Under-proofed is simply not finished — give it more time somewhere warmer, and be patient rather than raising the heat, since above about 40°C the yeast starts to die. Slightly over-proofed dough can be knocked back, reshaped and proofed again; it will be a little less lively but perfectly good. Badly over-proofed dough, slack and smelling strongly alcoholic, will not come back — bake it as a flatbread rather than pretending it is a loaf. Dough that never rose because the yeast was dead cannot be rescued by adding more yeast to a fully mixed dough; start again.
The mechanism
Yeast consumes sugars and produces carbon dioxide and ethanol. The gas cannot escape a properly kneaded dough because the gluten network is elastic and gas-tight, so it inflates thousands of tiny pockets and the dough expands. Two things govern the rate: temperature and food. Yeast works fastest around 25-30°C and slows sharply when cold, which is what a refrigerated overnight rise exploits — the slow fermentation produces more flavour compounds relative to gas. Enriched doughs, with sugar, butter and egg, rise more slowly rather than faster: sugar competes with the yeast for water and fat coats the gluten, so expect close to double the time a lean dough takes. Over-proofing is a real failure and not just excess: the gluten stretches past what it can hold, and the structure collapses in the oven.
The full TO PROOF lesson — how to tell, where to practise it, what it carries to.