Guide
How to Tell When Bulk Fermentation Is Done: The Aliquot Jar Method
The clock is a window. The dough is the decision. Temperature and starter amount tell you when to start paying attention. They do not tell you the minute bulk ends.
A fast starter, a young one, a dough that mixed warmer than you measured — all of them move the end. Your hands do not lie about it. The timer does.
This is the senses check. The temperature table already owns the hour. Use the hour to set an alarm. Use the dough to call it.
What finished bulk feels like
Tip the bowl. The mass should come away from the side in one piece and slump slowly, not pour. Pouring is early, or the dough was never developed. A brick that holds every angle is early.
Jiggle the bowl. You want a slow wobble, like set custard, not a splash. The whole dome moves. The surface shakes and settles. Batter-jiggle means the gluten never took the gas. No jiggle means the gas is not there yet.
The top should be domed, not flat, not collapsed. A dome means the dough is still holding what it produced. A crater in the middle means it produced it an hour ago.
Bubbles at the edge, against the bowl, are the easy visual. Small ones early. Larger, irregular ones near the end. A few bubbles on top are normal. A surface covered in large blisters is late.
The finger poke: flour a wet finger, press to the first knuckle. The dent should fill most of the way, slowly. Instant fill is early. A dent that stays is the end of the window, or past it. Shape at the slow fill. Do not wait for the dent that gives up.
The aliquot jar
A clear straight-sided jar. A small piece of the same dough, packed level, no big air pocket. Mark the start line. Anything from a shot glass to a small jam jar works if the sides are straight. A tapered bowl lies about volume.
The jar sits next to the bowl, same room, same temperature. It is the dough with the guessing removed. You can see the rise. You cannot see it as cleanly in a wide mixing bowl.
Check the sample when you check the bowl. Rising, domed, bubbles on the glass: still in bulk. Level with a mark you set for this dough, and the bowl passing the jiggle test: shape. Fallen sample: you are late. The jar fell because the dough fell.
Do not refrigerate the jar and leave the bowl out, or the reverse. Different temperatures make the sample a different dough. Same bench. Same clock.
The aliquot is a witness. It is not a second formula. If the jar says risen and the bowl is still a dense lump, the sample was loose or warm. Trust the bowl. Find out why the jar diverged.
Why the clock loses
The timing table assumes a dough temperature and a starter maturity. Both drift. Flour from the pantry cools the mix. A mixer warms it. A starter an hour past peak runs faster than a starter that just doubled. The formula cannot see any of that after you close the bowl.
An alarm at the early edge of the window is the right use of the clock. An alarm as a hard stop is how you shape early and bake a tight crumb, or miss the dome and bake a flat one.
Warm kitchen, fast bulk. The signs arrive compressed. Check more often. Cold kitchen, slow bulk. The same signs, spread out. Still the same signs. Jiggle does not care what time you started.
Calling it
Shape when three of these agree: dome, edge bubbles, slow poke, aliquot at the rise you marked, bowl releasing in one sluggish mass. One sign alone is not a verdict. A bubbly surface on a dense interior is a weak mix, not the end of bulk.
Past the dome, get it into a basket. More time will not add strength. It will spend it.