Formulas & Methodology
See the formulas behind BakerPercent's baker’s percentage, hydration, loaf scaling, and fermentation estimates.
1. The Baker’s Percentage Definition
In commercial and artisan baking, recipes are expressed relative to total flour weight, which is always standardized to exactly 100%. All other ingredients are expressed as:
2. Reverse Loaf Weight Derivation
When scaling backward from a target total dough weight (W_target) for N loaves of weight L:
Component weights are subsequently derived as:
- Added Water = Base Flour × (Hydration% / 100)
- Starter = Base Flour × (Starter% / 100)
- Salt = Base Flour × (Salt% / 100)
3. Starter Hydration Decomposition & True Hydration
A standard active starter at 100% hydration consists of equal parts water and flour by weight (1:1 ratio). For a starter with hydration H_s:
4. Fermentation Kinetics Model
The rate of fermentation in sourdough is predominantly governed by the temperature dependence of wild yeast (Saccharomyces cerevisiae / Candida humilis) and lactic acid bacteria (Lactobacillus sanfranciscensis).
BakerPercent uses an empirical Q_10 temperature coefficient approximation (Q_10 ≈ 2.1) centered at a baseline of 24°C (75°F) with 20% starter inoculation:
Because biological activity accelerates non-linearly at higher temperatures, target volume increases before shaping are dynamically decreased from 75% rise at 19°C (66°F) to 45% rise at 28°C (82°F) to prevent dough degradation during final shaping and bench rest.