How to Replace 2g (⅔ tsp) Instant Dry Yeast with Sourdough Starter in a 500g Flour Recipe
Zero-drift flour and water deduction guide for converting low-yeast (2g instant dry yeast) artisan or poolish doughs into 100g sourdough levain.
Start with the mass balance. 2g of instant dry yeast contributes no flour and no water to your dough; 28.6g of 100% hydration culture contributes 14.3g of each. So a 500g flour, 350g liquid formula becomes 485.7g flour and 335.7g liquid once the levain goes in, and the dough will ferment on sourdough's clock rather than yeast's.
- Direct Yeast Equivalent
- 28.6g StarterDeduct 14.3g flour & 14.3g water
- 20% Artisan Inoculation
- 100g StarterDeduct 50g flour & 50g water
- Adjusted Main Flour/Water
- 450g / 300gPreserves 500g total system flour at 20% levain
- Sourdough Bulk Window
- 4.0 – 5.5 hoursAt 76°F (24°C) vs. 1–1.5 hrs for commercial yeast
Yeast-to-Sourdough Conversion Table: 2g Instant Dry Yeast on a 500g Base
Rows recompute the full conversion independently, so the flour, liquid and starter columns always reconcile.
| Starter Hydration | Packet-Equivalent Starter (Deductions) | Adjusted Main Dough (Packet Mode) | 20% Artisan Starter (Deductions) | Adjusted Main Dough (20% Mode) |
|---|---|---|---|---|
| Case 1000g @ 100% [Primary] | 28.6g levain | subtract 14.3g flour, 14.3g water | 200g levain | subtract 100g flour, 100g water |
| Case 400g @ 50% Low Hydration | 28.6g levain | subtract 19g flour, 9.5g water | 80g levain | subtract 53.3g flour, 26.7g water |
| Case 500g @ 75% Mid Hydration | 28.6g levain | subtract 16.3g flour, 12.2g water | 100g levain | subtract 57.1g flour, 42.9g water |
| Case 500g @ 125% High Hydration | 28.6g levain | subtract 12.7g flour, 15.9g water | 100g levain | subtract 44.4g flour, 55.6g water |
| Case 500g @ 100% Standard 100% | 28.6g levain | subtract 14.3g flour, 14.3g water | 100g levain | subtract 50g flour, 50g water |
Live Parameter Solver for How to Replace 2g (⅔ tsp) Instant Dry Yeas
Dial in custom baker's percentages and export your adjusted 28.6g Starter formula for bake day.
Replacing Low-Inoculation 2g Instant Dry Yeast in 500g Flour Without Shifting Hydration
Hydration drift is the most common way this conversion goes wrong. Adding 28.6g of levain to 500g grain and 350g water without the 14.3g deduction pushes the dough to 70.8% true hydration, and the extra free water is exactly what turns a slack dough into a puddle.
A hybrid is often the best answer in practice: use 28.6g of levain to preserve the flavour of the original 2 grams dose, but plan the schedule as if you were using 100g at 20% inoculation, because the acid load and the fermentation time both follow the latter.
3-Step Conversion Checklist (2g Instant Dry Yeast → Sourdough in 500g Flour)
- Check the Starter Is Ripe: 100g of levain must be domed, bubbly and at full stretch; a flat culture slows the 4.0 – 5.5 hours at 76°F (24°C) window significantly.
- Combine 500g of Flour with the Adjusted Liquid: Pour 300g, saving 10% to dissolve the salt later.
- Fold in 100g Starter and 2% Salt: Add the levain, pinch through the dough, and work in the salt water.
- Ferment to +50%: Judge by volume in a straight-sided jar, then shape, retard overnight and bake on a preheated stone or in a Dutch oven.
Cereal Chemistry & Bench Execution FAQs
How much longer does sourdough take to rise than 2 grams of Instant Dry Yeast?
Expect bulk fermentation on a 500g flour batch to take 4.0 – 5.5 hours at 76°F (24°C), roughly 3 to 4 times longer than commercial instant dry yeast.
Does converting to sourdough change the dough weight?
Yes, slightly. The 500g flour and 350g liquid original carried 2 grams of dry yeast; the levain version carries 28.6g of starter instead, so expect a small shift in finished loaf weight.
How do I convert a sweet or enriched recipe with 2g of Instant Dry Yeast?
The flour and water deduction is identical, but reduce the sugar by about 10%–15%, because the 4.0 – 5.5 hours at 76°F (24°C) sourdough ferment converts more of it than a two-hour commercial rise.