You absolutely can leave your sourdough starter out overnight after feeding it, particularly if you are going to bake with it the next day. I highly recommend feeding it a higher ratio to prolong it's peak and ensure that it's ready for the you in the morning.
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.
You most definitely can bulk ferment sourdough too long. If you leave the dough to ferment for too long, it will become "over fermented". Over fermented dough will lose its structure and become a soupy, sloppy mess that you will not be able to shape.
Proofing sourdough overnight in the fridge is a great option if you like to bake first thing in the morning. What is this? You could plan out your sourdough baking timeline so that your bulk fermentation finishes in the evening. You would then shape your dough and place it into the fridge to proof overnight.
Can I bulk ferment in the refrigerator? No. The refrigerator is too cool for bulk fermentation. However, if you begin bulk fermentation at room temperature it is possible to move your dough into the refrigerator for the last hour or so of bulk fermentation.
When you put your dough in the fridge it slows the yeast activity down. It takes ten times longer for dough to rise in the fridge than it does at room temperature. This means you can put your dough in the fridge overnight or whilst you are at work and come back to it when you are ready.
Can you bulk ferment sourdough in the fridge? No - bulk fermentation should ideally be undertaken at room temperature. The yeast and bacteria in your sourdough starter perform best in warmer temperatures so placing them in the fridge will put them into a sleepy state.
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.
Dough appearance should no longer be rough after sourdough bulk fermentation. It should be smooth looking and even a bit shiny. If you lift up a section, it should move together. You should see the formation of lines of gluten strands and/or webs of gluten that have formed.
If you desire an extra-sour sourdough loaf, cover it and refrigerate immediately. The dough will rise slowly overnight or up to 24 hours.
Let rest in a warm spot to rise. The dough is ready when it no longer looks dense and has doubled in size. This can take anywhere from 3-12 hours depending on the temperature of your ingredients, the potency of your starter and surrounding environment.
Ideally, you don't want to allow sourdough bread to cold ferment for longer than 72 hours. Even up to 48 hours, you do risk some loss of gluten structure unless you manipulate the amount of starter down.
While some bakers use starters that only double in volume at peak activity, I'll tell you straight up: Don't settle. A starter that doubles in volume will work, but the overall fermentation and rising of dough might be slower, and the resulting bread potentially flatter.
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.
During cold bulk fermentation it should be sealed in an air-tight container or else the surface will dry out. My bowl and lid combo does not seal that well. Even if it works during shorter fermentation at room temperature, it does not work in the fridge.
The most common reason why sourdough bread is not rising is an immature starter, but if your starter is fully active, then it's likely that you've not given it enough time to ferment. Give your sourdough bread at least 4 hours to bulk ferment, plus a further 3-4 hour second rise before baking.
Overproofed is when the dough has rested too long and the yeast has continued making carbon dioxide while the strength of the dough (gluten bonds) have begun to wear out. The dough will look very puffy, but when you touch it or move it you may notice it deflate or sag.
Overproofed sourdough dough loses all structure, so it's stretchy and slack when turned onto a work surface. The dough is also stickier than usual due to the lack of remaining gluten structure.
You could bake it in a loaf or cake tin to hold the shape. Place it in very gently, hopefully, it fits your baking method vessels! Don't slash it and bake it immediately. If the indent springs back gently but not completely, your sourdough bread is ready to bake!
If left overnight, the dough can rise so high it will likely collapse on the weight of itself, making the dough deflate. For best results, always keep the dough in the refrigerator when leaving it to rise overnight.
After kneading, put the dough in a greased bowl and cover with greased plastic wrap and place in the fridge. Punch the dough down after it's been in the fridge for 1 hour, then punch it down once every 24 hours after that. Dough will keep in the fridge for 3 days but it's best used within 48 hours.
“If the dough has risen too long, it's going to feel fragile and might even collapse as you poke it,” says Maggie. If this is the case, there's a chance you can save your dough by giving it a quick re-shape. Learn more about this fix in our blog on saving overproofed dough.
If the dough isn't mixed or kneaded to full development (e.g., full windowpane), adding in sets of stretch and folds during bulk fermentation will help continue its progress toward a stronger, more cohesive dough that's able to trap gas and hold its shape all the way to bake time.
Just like adding more yeast to a yeasted dough makes it rise quicker, increasing the amount of starter used in your dough will speed up the sourdough fermentation process. If you want to rapidly increase the proofing speed of sourdough you can, if you wish, add some baker's yeast to the recipe.
The target bulk fermentation temperature range is 78-82F / 25.5-28C. Use a proofing chamber, if necessary, to keep a consistent dough temperature throughout bulk fermentation and continuously measure the dough temperature every 30 minutes at minimum.