Convert 80g Sourdough Starter (80% Hydration) to Commercial Yeast
How to remove 80g of 80% hydration levain from any sourdough recipe by restoring +44.4g flour and +35.6g water.
If your goal is a commercial-style crumb, work out the yeast for the schedule you actually want. The same 80 grams of 80% starter on a 450g base needs 6.9g (2.2 tsp) of instant yeast for a 1.5 – 2.0 hours warm bulk rise, and a fraction of that if you plan a cold overnight ferment instead.
- Add Back Flour
- +44.4gReplaces flour inside 80g (80%) starter
- Add Back Water
- +35.6gReplaces water inside 80g (80%) starter
- Instant Yeast (2-Hr Rise)
- 6.9g (2.2 tsp)For 494.4g total flour batch
- Preserved Hydration
- 70.9%350.6g W / 494.4g F
Instant, Active Dry & Fresh Yeast for 80g of 80% Starter
Neighbouring starter weights are included so you can scale the swap up or down from the same base formula.
| Fermentation Speed | Instant Yeast (g / tsp) | Active Dry Yeast (g / tsp) | Fresh Yeast (g) | Add Back Flour & Water |
|---|---|---|---|---|
| Line 80g / 80% [Your Batch] | 6.9g IDY (2.2 tsp) | 8.7g ADY (2.8 tsp) | 20.8g cake yeast | 1.5 – 2.0 hours warm bulk rise |
| Line 70g / 80% Scaled Down | 3.4g IDY (1.1 tsp) | 4.3g ADY (1.4 tsp) | 10.3g cake yeast | 3.5 – 4.5 hours slow room-temp rise |
| Line 90g / 80% Scaled Up | 1.3g IDY (0.4 tsp) | 1.6g ADY (0.5 tsp) | 3.8g cake yeast | 12 – 18 hours cold fermentation (39°F / 4°C) |
| Line 60g / 80% Trimmed | 6.8g IDY (2.2 tsp) | 8.5g ADY (2.7 tsp) | 20.3g cake yeast | 1.5 – 2.0 hours warm bulk rise |
| Line 100g / 80% Expanded | 3.5g IDY (1.1 tsp) | 4.4g ADY (1.4 tsp) | 10.6g cake yeast | 3.5 – 4.5 hours slow room-temp rise |
Real-Time Dough & Starter Scaling Sandbox
Scale this Convert 80g Sourdough Starter (80% H specification up or down on your digital scale with zero hydration drift.
Decomposing 80g of 80% Hydration Starter: Flour + Water Conservation
Converting a levain to commercial yeast also converts a flavour problem. The 2g of residual lactic and acetic acid inside 80g of starter contributes aroma and dough-softening that no commercial yeast can replace, so a converted dough usually benefits from a little extra fat or a riper flour.
Freezing is easier without a levain. Commercial-yeast dough tolerates a freeze at the point of shaping much more readily, which makes a 1.5 – 2.0 hours warm bulk rise schedule easy to batch around.
Step-by-Step Reverse Conversion Protocol (80g @ 80%)
- Dissolve the Yeast: Bloom 6.9g of IDY in a little of the 35.6g restored water at 100°F (38°C) so it disperses evenly through the 494.4g of flour.
- Combine Dry and Wet: Add the 44.4g of restored flour to the original flour, pour in the 350.6g of water and the yeast slurry, and mix until no dry flour remains.
- Add Salt Last: Work 2% salt into the dough and continue mixing until a windowpane forms.
- Single Bulk, No Folds Needed: Let the dough rise undisturbed for 1.5 – 2.0 hours warm bulk rise, then shape, prove briefly and bake.
Diagnostic Answers: Convert 80g Sourdough Starter (80% Hydration
Can I use fresh cake yeast instead of dry yeast for the 80g starter swap?
Yes, but fresh compressed yeast is only about a third as potent per gram, so you need roughly 20.7g instead of 6.9g.
How much instant yeast replaces 80 g of 80% sourdough starter?
For a standard 1.5–2 hour rise on a 494.4g total flour loaf, use 6.9g (2.2 tsp) of Instant Dry Yeast and add back 44.4g flour + 35.6g water.
How long should the converted dough bulk for at room temperature?
Plan on 1.5 – 2.0 hours warm bulk rise, then shape and bake immediately. There is no levain to justify a long slow bulk, and a commercial-yeast dough left longer simply over-proofs.