Convert 200g Sourdough Starter (80% Hydration) to Commercial Yeast
How to remove 200g of 80% hydration levain from any sourdough recipe by restoring +111.1g flour and +88.9g water.
If your goal is a commercial-style crumb, work out the yeast for the schedule you actually want. The same 200 g of 80% starter on a 450g base needs 7.9g (2.5 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
- +111.1gReplaces flour inside 200g (80%) starter
- Add Back Water
- +88.9gReplaces water inside 200g (80%) starter
- Instant Yeast (2-Hr Rise)
- 7.9g (2.5 tsp)For 561.1g total flour batch
- Preserved Hydration
- 72%403.9g W / 561.1g F
Reverse Conversion Chart: 200g Starter → Commercial Yeast
Each row re-derives the yeast dose from total flour and the fermentation schedule rather than from the starter weight.
| Fermentation Window | Instant Yeast Grams (Teaspoons) | Active Dry Yeast Grams (Teaspoons) | Fresh Cake Yeast Grams | Flour & Water to Put Back |
|---|---|---|---|---|
| [Your Batch]: 200g starter at 80% | instant 7.9g | active dry 9.8g | fresh 23.6g | bake 1.5 – 2.0 hours warm bulk rise |
| Scaled Down: 210g starter at 80% | instant 4g | active dry 5g | fresh 11.9g | bake 3.5 – 4.5 hours slow room-temp rise |
| Scaled Up: 190g starter at 80% | instant 1.4g | active dry 1.7g | fresh 4.2g | bake 12 – 18 hours cold fermentation (39°f / 4°c) |
| Trimmed: 220g starter at 80% | instant 8g | active dry 10g | fresh 24g | bake 1.5 – 2.0 hours warm bulk rise |
| Expanded: 180g starter at 80% | instant 3.9g | active dry 4.8g | fresh 11.6g | bake 3.5 – 4.5 hours slow room-temp rise |
Real-Time Dough & Starter Scaling Sandbox
Scale this Convert 200g Sourdough Starter (80% specification up or down on your digital scale with zero hydration drift.
Decomposing 200g of 80% Hydration Starter: Flour + Water Conservation
Salt interacts with the change. A levain dough was usually formulated for a 2% salt dough, and swapping in 7.9g of commercial yeast on the same 561.1g of flour keeps that salt level, which is a sensible place to leave the formula alone.
Shelf life shortens. The 72% hydration dough leavened by 7.9g of yeast stales faster than the levain version, because there is no residual acid to slow starch retrogradation.
Step-by-Step Reverse Conversion Protocol (200g @ 80%)
- Use a Scale, Not a Spoon: 7.9g of instant yeast is 2.5 teaspoons, and a kitchen teaspoon of yeast varies by up to 20% between brands, so weighing is the only accurate approach.
- Combine Everything at Once: 561.1g flour, 403.9g water at 100°F (38°C), 7.9g yeast and 2% salt.
- Knead to Windowpane: A commercial-yeast batch develops gluten faster, so stop as soon as the gluten film is smooth and you will avoid tearing it.
- Proof and Bake: Allow 1.5 – 2.0 hours warm bulk rise, shape once, and bake the moment the volume has roughly doubled.
Diagnostic Answers: Convert 200g Sourdough Starter (80% Hydratio
Will my converted dough taste different from the levain version?
Yes. The roughly 4g of residual acid inside 200 grams of starter was providing both flavour and tenderising, and commercial yeast replaces neither.
Can I use fresh cake yeast instead of dry yeast for the 200g starter swap?
Yes, but fresh compressed yeast is only about a third as potent per gram, so you need roughly 23.7g instead of 7.9g.
Why is my converted dough less extensible than the original?
Usually because the 88.9g of restored water was not added, leaving the dough drier and tighter, or because the levain's proteolysis was doing part of the gluten-softening work.