Coil folds: when and why

Stretch-and-fold works beautifully up to about 75% hydration. Past that, the dough gets too slack to fold the conventional way without tearing it apart. Above 80% hydration, you need a different approach. Coil folds are the answer most modern sourdough bakers have settled on.

The mechanics are different but the goal is the same: build gluten, distribute gas, equalise temperature. Coil folds just achieve it more gently.

What a coil fold looks like

Wet your hands. Reach under the centre of the dough from one side. Lift the entire dough mass up; the dough will sag down on both sides as you lift, naturally folding in on itself. Lower the dough back into the bowl, letting the sagging sides settle underneath. Rotate the bowl 90°. Lift again from the new centre. Lower. Rotate. Repeat one more time.

The whole motion is a single smooth lift-and-lower, repeated four times around the bowl. Total time per set: about 20 seconds. Less aggressive than stretch-and-fold, faster to perform, far gentler on the dough's already-formed bubble structure.

Why this works for slack doughs

Two reasons stretch-and-fold fails above 80% hydration:

1. 1.The dough is too sticky to grab cleanly. Even with wet hands, you end up tearing chunks rather than lifting an edge cleanly.
2. 2.The dough doesn't have enough internal cohesion to hold a stretch. When you pull on one edge, the whole dough mass slides instead of stretching; there's nothing to anchor against.

Coil folds work around both problems by lifting from the centre. There's no edge-grabbing, and the dough's own weight does the stretching as it sags. The dough literally folds itself.

When to switch from stretch to coil

The rough hydration thresholds:

• Below 75%: Stretch-and-fold works well. Coil folds also work but offer little advantage.
• 75–80%: Either works. Many bakers do the first 1–2 sets as stretch-and-fold (when the dough is still cohesive enough) then switch to coil folds for the later sets (when the dough has relaxed and gas has built up).
• 80–85%: Coil folds are clearly better. Stretch-and-fold becomes destructive at this hydration.
• Above 85%: Coil folds, gently. Some doughs at this hydration are too slack even for coils; use a wet bench scraper to gently lift and fold instead.

The mixed-method approach

Many serious sourdough bakers use both techniques in the same bake.

First two sets: stretch-and-fold. The dough is still slack from initial mixing; strong stretches build the gluten network when there's still slack to take up.

Final two sets: coil folds. The gluten is now developed and gas has accumulated. Coil folds redistribute the gas without disturbing the structure aggressively, exactly what you want as the dough approaches the end of bulk fermentation.

This is the technique you'll see in most open-crumb sourdough demonstrations on YouTube. The early aggressive folds build the structure; the late gentle coils preserve it.

Common mistakes

Lifting too high

If you lift the dough so high it stretches all the way out to a thin sheet before folding, you've defeated the purpose; that's just an aggressive stretch-and-fold. Lift only as high as needed to let the sides sag and fold naturally underneath. For most doughs, that's 4–6 inches / 10–15 cm above the bowl rim.

Doing too many sets

Coil folds are gentle, but they still disturb the gas. Three sets total is usually enough; four if the dough started weak. More than four risks deflating the structure you're trying to preserve.

Not waiting long enough between sets

Coil folds work best with longer rests between them than stretch-and-folds. 45 minutes between coils is the standard, vs. 30 minutes for stretch-folds. The dough needs time to relax between gentle interventions.

How to tell coils worked

After a coil fold, the dough should sit in the bowl as a smooth, slightly domed mass. The surface should look glossy. Small bubbles should be visible at the edges where the dough meets the bowl. By the third set, the dough should be holding more shape than after the first, same as with stretch-and-folds, just achieved more gently.

Doughs where coils don't help

• Lower-hydration doughs. No advantage over stretch-and-fold and arguably less effective at building gluten when the dough has plenty of slack to absorb stronger work.
• Enriched doughs. Brioche and similar doughs need the strong mechanical work of a stand mixer; gentle folds don't develop enough gluten through fat content.
• Same-day commercial-yeast breads. Coil folds are paced for the timeline of a sourdough bulk fermentation. Same-day breads ferment too fast to benefit from 45-minute rest intervals.

The takeaway

Coil folds are stretch-and-fold's gentler sibling for slack, high-hydration doughs. Above 80% hydration, switch to coils. Between 75% and 80%, mix the methods: stretch early, coil late. Below 75%, stretch-and-fold remains the better choice.