Total After Feeding
150g
Flour
50g
Water
50g
Peak
6–8h
Leave empty for maintenance feeding only
Feed once daily if keeping at room temperature, or once weekly if refrigerated.
| Temp | Peak Time |
|---|---|
| 65°F | 10–12h |
| 70°F | 8–10h |
| 75°F | 6–8h |
| 80°F | 4–6h |
| 85°F | 3–4h |
Times for 1:1:1 ratio with all-purpose flour. Higher ratios and whole grains ferment faster.
Inputs
Result
50g starter + 50g all-purpose flour + 50g water = 150g total. At 75°F, expect peak activity in 6–8 hours. Before the next feeding, discard back to 50g. This is the simplest and most common maintenance routine.
Inputs
Result
25g starter + 125g bread flour + 125g water = 275g total. The high ratio slows fermentation to 12–15 hours at 70°F, perfect for mixing at 9 PM and using at 9 AM. Ideal for overnight levain builds.
Inputs
Result
50g starter + 100g whole wheat flour + 100g water = 250g total. Whole wheat ferments faster due to higher mineral and enzyme content. At 80°F, this peaks in just 3–5 hours — feed twice daily or refrigerate between feedings.
The ideal feeding ratio depends on your schedule and kitchen temperature. A 1:1:1 ratio (equal parts starter, flour, water by weight) is the quickest feed, peaking in 4–6 hours at 75°F. A 1:5:5 ratio uses less starter relative to flour, slowing fermentation to 8–12 hours — perfect for overnight levain builds.
| Ratio | Peak at 75°F | Flour Used per 50g Starter | Best For |
|---|---|---|---|
| 1:1:1 | 4–6h | 50g | Quick same-day bake |
| 1:2:2 | 6–8h | 100g | Daily maintenance |
| 1:3:3 | 7–9h | 150g | Overnight room-temp |
| 1:5:5 | 9–12h | 250g | Long overnight levain |
Temperature is the single biggest factor controlling fermentation speed. At 65°F, a 1:1:1 feeding peaks in 10–12 hours. At 80°F, the same feeding peaks in just 4–6 hours. Every 5°F increase cuts roughly 1–2 hours off peak time. This is why bakers adjust feeding ratios seasonally.
| Temperature | Peak (1:1:1) | Feed Frequency | Tip |
|---|---|---|---|
| 65°F | 10–12h | Once daily | Use higher ratio to extend |
| 70°F | 8–10h | Once daily | Standard maintenance |
| 75°F | 6–8h | 1–2x daily | Ideal for baking day |
| 80°F | 4–6h | Twice daily | Watch for over-fermentation |
| 85°F | 3–4h | 2–3x daily | Refrigerate if not baking |
Starter hydration is the percentage of water relative to flour by weight. A 100% hydration starter has equal parts flour and water (e.g., 50g flour + 50g water), producing a thick batter-like consistency. Lower hydration (50–75%) creates a stiffer starter that ferments more slowly and develops more acetic acid (vinegar tang). Higher hydration (125–150%) creates a liquid starter that ferments faster.
Discard depends on how much starter you maintain and your feeding ratio. If you keep 50g of starter and feed 1:1:1, you add 100g (50g flour + 50g water) for a total of 150g. Before the next feed, you discard back down to 50g, meaning 100g of discard. Higher ratios produce more discard per cycle. You can reduce waste by maintaining a smaller starter (25–30g).
| Starter Kept | Ratio | Discard/Feed | Weekly Flour (daily feeds) |
|---|---|---|---|
| 25g | 1:1:1 | 50g | 175g |
| 50g | 1:1:1 | 100g | 350g |
| 50g | 1:2:2 | 250g | 700g |
| 100g | 1:1:1 | 200g | 700g |
To build a levain, take a portion of your active starter and feed it at your preferred ratio to reach the total weight your recipe needs. For example, if a recipe calls for 150g of levain at 100% hydration using a 1:2:2 ratio, mix 30g starter + 60g flour + 60g water = 150g total. Build the levain 6–12 hours before you plan to mix your dough, and use it at peak activity.
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Last Updated: Mar 9, 2026
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