Oil in a sourdough loaf usually buys softness and costs structure. Add it at the start and the gluten never develops properly, so you get a tender brick. Add 20% olive oil — measured against flour weight, not against water — after the second fold, and the dough has already built its network. The result keeps the open crumb and stays soft for three days instead of one.
When the oil goes in, exactly
The first two folds happen with no fat at all. At the second fold the dough already stretches to 40 cm without tearing. Only then do I drizzle 20 g of olive oil per 100 g of flour over the surface and fold it in with four coil folds, letting each addition absorb before the next.
| Fold | Minutes from mix | Oil added | Dough feel |
|---|---|---|---|
| 1 | 0 | none | Tacky, tears at 20 cm |
| 2 | 40 | 40% of the oil | Slippery at first, then glossy |
| 3 | 80 | 30% of the oil | Silky, no longer sticks to the tub |
| 4 | 120 | 30% of the oil | Soft, holds a window easily |
Why 15% whole wheat appears in an oily dough
Whole wheat has more damaged starch and more bran surface, and both soak up free oil. Without it, 20% olive oil makes the dough so slippery that it will not hold a seam and the shaped batard flattens in the banneton. The 15% whole wheat raises the water absorption too, so the effective hydration feels higher than the printed 76%.
Baking a dough with fat in it
Fat slows crust colouring, so this loaf goes in at 235 °C with 20 minutes of steam and finishes at 43 minutes — slightly paler than the baseline, with a thin, tender crust rather than a shattering one. Score a curved ear slash plus a small cross cut: an oily dough seals its cuts faster than a lean one.
- Internal temperature 96 °C, but check at 40 minutes; oil conducts heat differently.
- Cool completely, at least three hours. Cutting warm gives a soapy aftertaste.
- Day three is still good; day four the crust softens but the crumb is fine for toast.
If the dough feels greasy rather than silky, you added oil before the gluten was ready. Fold the oil in more slowly next time, and wait for the dough to pass the window check before the first addition.