Ideally, you don't want to allow sourdough bread to cold ferment for longer than 72 hours.
After kneading, shape your loaf, cover it, and let it proof for 4-24 hours, depending on your specific sourdough starter and ambient temperature. You can manipulate the sourness of the bread with a longer rise time.
The dough will rise slowly overnight or up to 24 hours. Allowing the dough to remain longer in the refrigerator isn't beneficial, as an extended time in the refrigerator will lead to off flavors and diminished dough strength.
Bulk fermentation can typically last anywhere from 3.5 to 7 hours depending on the dough temperature, recipe, and amount of sourdough starter used. At 78ºF, bulk fermentation usually lasts about 4-4.5 hours for my typical sourdough bread.
For a typical sourdough bread recipe, I let bulk fermentation play out at room temperature over 3 to 5 hours. But this time period is ultimately dictated by the bread you're making, what the recorded desired dough temperature is, and the temperature at which you keep the dough.
Because the dough is fermenting during both rises, if the process goes on for too long, the finished loaf of bread can have a sour, unpleasant taste. The finished loaf usually also has a dense texture and isn't sufficiently chewy. Over-proofed loaves of bread have a gummy or crumbly texture.
Properly proofed sourdough bread undergoes the oven spring, which is the final expression of the carbon dioxide gasses in the oven. An overproofed dough lacks the necessary carbon dioxide gas for the added boost. The result is a flat, squat loaf of bread with a tight, gummy crumb.
Dough volume should be at least double from the gas built up from yeast fermentation. There should be visible signs of the bubbles of gas on top and from side if you have a see-through bowl or container. Sometimes the dough even jiggles from this built up gas–that's a good sign!
Gently press your finger into the dough on the top. If the dough springs back quickly, it's underproofed. If it springs back very slowly, it's properly proofed and ready to bake. Finally, if it never springs back, the dough is overproofed.
While underworked dough can simply be fixed by a little more kneading, severely overworked dough cannot be fixed. Instead, the overworked dough will result in a hard loaf that will likely not be eaten. It's important not to overwork your dough and continually check for overworking throughout the kneading process.
You can absolutely leave sourdough bread to rise overnight - but as always - there are some things you'll need to do to make sure that your bread is successful with an overnight ferment.
This fermentation allows the natural yeast the time needed to raise the bread. An 8-10 hour rise is common for this overnight fermented or “bulk” rise. So, preparing the sourdough in the evening, and letting it rise overnight is ideal. Within a few hours of waking, you'll have fresh sourdough bread.
Sourdough bread can be time consuming to make, and it can be difficult to fit it all in in just one day. Leaving it to rise in the fridge overnight means you can just pop it into the oven the next morning. This can be handy if you don't want to spend all day in the kitchen, or simply need to go out during the day.
Room-temperature starter should be fed every 12 hours (twice a day) using the standard maintenance feeding procedure: discard all but 113g, and feed that 113g starter with 113g each water and flour.
When the bulk fermentation goes too long — often when the dough more than doubles or triples in volume — the dough can over ferment. You know the dough has over fermented if, when you turn it out to shape it, it is very slack — if it's like a wet puddle — and very sticky and lacking any strength and elasticity.
The longer you leave your dough in the refrigerator, the more sour and complex flavors it will develop. You can easily leave a loaf in the refrigerator for 3 days before baking. I've gone as long as 5 days, but you will see some deterioration of the loaf after Day 3.
To proof them, let them sit, covered, at room temperature for up to 3–4 hours, or let them proof for a little while at room temperature and then place in the refrigerator for 12–15 hours. Or you can speed the process by using a proof box, warm cooler, or slightly warm oven to speed things up.
Generally your fridge will be 4 degrees or below - making it way too cold for the yeast to happily work. The only way you could do the bulk ferment in the refrigerator is if you left it there for a considerable amount of time - like between 3 and 7 days.
A Mature Sourdough Starter is More Sour Than a Young One
If you have made a starter from scratch, it doesn't fully mature and develop its full depth of flavor until a good few months down the line. A more mature sourdough starter will give a more sour flavor. So be patient, and give your starter time to mature.
The good news: We found an easy way to rescue overproofed dough. Simply punch it down gently, reshape it, and let it proof again for the recommended amount of time. In the test kitchen, these steps resulted in bread that tasters found acceptable in both texture and flavor.
What to look for in an over proofed loaf. Similar to the signs of over proofed dough, an over proofed loaf will be very flat, without much rise or retention of shaping. Over proofing destroys the structural integrity of the bread, so loaves that have gone over are unable to hold their shape in the oven.
If you want to let you dough proof for longer, try bulk-fermenting it in a cooler place, but don't allow it to go longer than three hours or structure and flavor may be compromised. For the workhorse loaf, a bulk proof of approximately two hours gives us the optimal balance of flavor and texture.
What Happens if I Proof my Dough for Too Long? There is of course a limit to how long you can proof your sourdough for. And if you do leave it too long, it eventually runs out of its food source (the starches and sugars in the dough), and over ferments.
A loaf bulk fermenting at 70F/21C may take 12 hours to reach a target rise of 75%. At the 75% rise, the dough is shaped, where it rises 5% more to approximately 80%. The dough then goes into the refrigerator where its rise curve flattens fairly quickly and it slowly rises to 100% over the next 12 hours.